Communication method and related device

Abstract

The invention provides a communication method and a related device. In the method, after a baseband chip obtains a first symbol sequence to be transmitted, modulation is carried out based on a third symbol sequence containing extended symbols and symbols to be transmitted in the first symbol sequence, and after (N + M) modulation symbols are obtained, the (N + M) modulation symbols are mapped to RE to obtain a second symbol sequence. The second symbol sequence is continuous in phase, and the difference between the head phase and the tail phase is an integral multiple of 2 pi. The CP of the OFDM baseband signal generated by the second symbol sequence and the signal body are continuous in phase, and phase jump does not exist. A phase or frequency modulation mode, such as CPM or LFM, is further adopted for modulation, a waveform with a continuous phase and a constant amplitude can be obtained, and therefore a constant envelope waveform can be obtained. When the method is applied to communication equipment, such as IoT (Internet of Things) equipment, the structure of a transmitter can be simplified, the transmission power consumption is reduced, and the standby life is prolonged.

Description

[0001] This application claims the priority of the Chinese patent application with the application number 202311549303.4 and the application title "Communication Method and Related Devices" submitted to the Chinese Patent Office on November 17, 2023, the entire content of which is incorporated herein by reference. Technical Field

[0002] This application relates to the field of wireless communication, and in particular, to a communication method and related devices. Background Art

[0003] With the development of wireless networks and the evolution of service requirements, the forms of terminal devices have gradually become diversified. Some terminal devices, such as Internet of Things (IoT) nodes, etc., have low costs and small volumes, and usually do not carry large-capacity batteries, so they face the problem of short standby life.

[0004] A possible solution to improve the standby life of such terminal devices is to reduce the transmission power consumption. Currently, there are already solutions proposed to directly perform upconversion on the baseband signal to eliminate the power consumption brought by the mixing operation; and use a non-linear power amplifier (PA) to replace the linear PA to further reduce the transmission power consumption. However, this solution has strict requirements on the waveform, that is, a constant envelope waveform with a peak to average power ratio (PAPR) of 0 decibels (dB) needs to be used for data transmission.

[0005] The current cellular network uses orthogonal frequency division multiplexing (OFDM) technology. To avoid interference between OFDM symbols, a guard period is usually inserted in the form of a cyclic prefix (CP) between OFDM symbols. The CP is usually formed by copying the signal at the tail of the OFDM symbol to the head, which cannot ensure the phase continuity between the CP and the signal behind it, and thus cannot ensure a constant waveform envelope. Therefore, how to generate a phase-continuous waveform based on OFDM technology has become an urgent technical problem to be solved. Summary of the Invention

[0006] This application provides a communication method and related devices, aiming to be able to combine phase or frequency modulation technology with OFDM technology to obtain a phase-continuous waveform, which is beneficial to obtaining a constant envelope waveform, and then applying it to communication devices to reduce the transmission power consumption.

[0007] In a first aspect, a communication method is provided. This method can be applied to a first communication device, which can be a communication device (such as a terminal device or a network device), or can also be a component for the communication device (such as a baseband chip, a chip system, a processor, etc.), or can also be a logical module or software that can implement all or part of the functions of the communication device, etc. This application does not make any limitation in this regard.

[0008] Exemplarily, the method includes: obtaining a first symbol sequence, where the first symbol sequence includes N symbols to be transmitted, and N is a positive integer; based on the first symbol sequence, obtaining a second symbol sequence, where the symbols in the second symbol sequence are obtained by mapping (N + M) modulation symbols to resource elements (REs), and the (N + M) modulation symbols are obtained by modulating a third symbol sequence, and the third symbol sequence includes the N symbols to be transmitted in the first symbol sequence and M extended symbols, and the M extended symbols make the phases of the (N + M) modulation symbols obtained by the modulation continuous, and the phase difference between the starting position and the ending position is an integer multiple of 2π, and M is an integer greater than or equal to zero; generating a first OFDM baseband signal based on the second symbol sequence, and the time-domain resource of the first OFDM baseband signal is one OFDM symbol.

[0009] Among them, the first symbol sequence can be a sequence composed of N symbols to be transmitted obtained through modulation. Through modulation, binary bits "0" or "1" can be mapped to symbols. The modulation used in this application can include, but is not limited to, modulation methods that can implement one-dimensional modulation such as pulse amplitude modulation (PAM), π / 2 - binary phase shift keying (BPSK), BPSK, and quadrature phase shift keying (QPSK). One-dimensional modulation can refer to a modulation method that modulates in one of the three dimensions of amplitude, phase, or frequency. Through one-dimensional modulation, a value in a certain dimension on the complex plane can be obtained as the output result, or in other words, a real number or a pure imaginary number output can be obtained.

[0010] The third symbol sequence can include the N symbols to be transmitted in the first symbol sequence and M extended symbols. It should be understood that the extended symbols are named for the convenience of distinguishing from the N symbols to be transmitted and should not constitute any limitation to this application.

[0011] Adding M extended symbols to the first symbol sequence can, without changing the N symbols to be transmitted and their order, through the design of the M extended symbols, make the phase of the modulated symbol sequence (for convenience of distinction and explanation, denoted as the fourth symbol sequence) obtained after modulating the third symbol sequence continuous, and the phase difference between the starting position and the ending position is an integer multiple of 2π. Due to the periodicity of trigonometric functions, when the phase difference between the starting and ending positions of the fourth symbol sequence is an integer multiple of 2π, the values of its sine or cosine functions are equal, that is, the phases of the starting and ending positions of the fourth symbol sequence are also continuous.

[0012] Among them, the continuous phase of the fourth symbol sequence can be achieved through some currently known phase or frequency modulation methods. The phase difference between the starting position and the ending position of the fourth symbol sequence being an integer multiple of 2π can be achieved through the design of the M extended symbols on the basis of adopting these phase or frequency modulation methods.

[0013] It can be understood that the symbols in the fourth symbol sequence are (N + M) modulated symbols. The starting position of the fourth symbol sequence is the starting position of the first symbol among the (N + M) modulated symbols included in the fourth symbol sequence, and the ending position of the fourth symbol sequence is the ending position of the last symbol among the (N + M) modulated symbols included in the fourth symbol sequence. The phase difference between the starting position and the ending position of the fourth symbol sequence, that is, the phase difference between the head and tail of the (N + M) modulated symbols, can also be said that the (N + M) modulated symbols satisfy head-to-tail phase self-circulation, or rather, the fourth symbol sequence satisfies head-to-tail phase self-circulation.

[0014] Mapping the (N + M) modulated symbols in the fourth symbol sequence to the REs can obtain the second symbol sequence. Therefore, the second symbol sequence is the modulated symbols mapped to the REs (or rather, mapped to the subcarriers), or rather, the second symbol sequence is obtained by mapping the (N + M) modulated symbols in the fourth symbol sequence to the REs. Since the RE mapping specifically refers to frequency-domain mapping, the (N + M) modulated symbols in the fourth symbol sequence can be converted to the frequency domain to complete the RE mapping. Therefore, it can be considered that the second symbol sequence is the representation of the (N + M) modulated symbols in the fourth symbol sequence in the frequency domain. Therefore, the fourth symbol sequence and the second symbol sequence are named only to distinguish the symbol sequences in the time domain and the frequency domain. The phases of the (N + M) modulated symbols in the fourth symbol sequence are continuous, and the phase difference between the starting position and the ending position is an integer multiple of 2π, that is, the phase of the second symbol sequence is continuous, and the phase difference between the starting position and the ending position is an integer multiple of 2π, or rather, the second symbol sequence satisfies head-to-tail phase self-circulation.

[0015] It can be understood that the OFDM baseband signal includes two parts: the body of the baseband signal and the CP. The generation of the OFDM baseband signal includes the generation of the signal body and the generation of the CP. The first OFDM baseband signal in the present application is generated based on the second symbol sequence. Among them, the signal body of the first OFDM baseband signal can be generated based on the second symbol sequence, and the CP of the first OFDM baseband signal can be part of the symbols at the end of the signal body (such as K 1 modulation symbols) are copied to its head. And the K 1 The modulation symbol corresponds to the K at the end of the aforementioned (N+M) modulation symbols 1 modulation symbols, so it can also be said that the CP of the first OFDM baseband signal is based on the K at the end of the (N+M) modulation symbols 1 modulated symbols. Those skilled in the art will know that the time domain resource of the CP is located before the OFDM symbol of the signal body, corresponding to the CP length, and the frequency domain resource of the CP is the same as the subcarrier mapped by the signal body. That is, K corresponding to the CP in this application 1 modulation symbols do not participate in RE mapping. In other words, the second symbol sequence does not include K used to generate CP 1 symbols.

[0016] Since the second symbol sequence satisfies the self-loop of the head and tail phases, the signal body of the first OFDM baseband signal generated based on the second symbol sequence also satisfies the self-loop of the head and tail phases. The partial symbols at the end of the signal body are copied to the head to obtain the CP of the first OFDM baseband signal. The CP of the first OFDM baseband signal is phase-continuous with the body. Therefore, the difference between the phase at the start position and the phase at the end position of the (N+M) modulation symbols is an integer multiple of 2π, which can be regarded as a constraint condition for determining the M extended symbols, that is, a constraint condition for determining the third symbol sequence.

[0017] On the contrary, if the extended symbol is not added to the first symbol sequence, the object of modulation is the first symbol sequence. If the first symbol sequence is modulated directly, and then RE mapping and OFDM baseband signal are generated based on the obtained modulation symbol sequence, the signal body of the obtained OFDM baseband signal may not satisfy the head and tail phase self-circulation, so there may be a phase jump between the signal body and the CP, that is, the phase of the OFDM baseband signal is discontinuous.

[0018] It should be noted that in some cases, the symbol sequence obtained after modulating the first symbol sequence already satisfies phase continuity and has a self - cycling phase at the beginning and end. In this case, no additional symbols need to be added to the first symbol sequence, that is, M can be zero, and the third symbol sequence is the same as the first symbol sequence. Of course, additional symbols can also be added to the first symbol sequence so that the phase of the second symbol sequence obtained after modulating the third symbol sequence is continuous and has a self - cycling phase at the beginning and end, that is, M is greater than zero, and the third symbol sequence is different from the first symbol sequence.

[0019] Based on the above - mentioned technical solution, by expanding the first symbol sequence, a third symbol sequence is obtained, and then based on the third symbol sequence, modulation and RE mapping are performed to obtain a second symbol sequence. The second symbol sequence obtained thereby can simultaneously satisfy: phase continuity and a self - cycling phase at the beginning and end. The signal body of the first OFDM baseband signal generated based on this second symbol sequence and the CP also satisfy phase continuity. On this basis, if the modulation technology adopted is a modulation technology that can maintain a constant amplitude, a waveform with continuous phase and constant envelope can be obtained. In this way, a scheme of combining phase or frequency modulation technology and OFDM technology to obtain a constant - envelope waveform can be realized. Since the constant - envelope waveform meets the requirements of direct conversion and non - linear power amplification for the waveform, the communication device can use some more power - saving ways to transmit signals. In addition, further, for communication devices (especially IoT nodes with small volume and without large - capacity batteries), their standby life can be improved.

[0020] In the following text, for the convenience of distinguishing the CP of the first OFDM baseband signal from that of other OFDM baseband signals, the CP of the first OFDM baseband signal is denoted as the first CP, and the sequence composed of the modulation symbols used to generate this first CP is denoted as the first CP sequence.

[0021] Combined with the first aspect, in some possible implementation manners of the first aspect, the modulation includes continuous phase modulation (CPM) or linear frequency modulation (LFM).

[0022] Among them, CPM is a type of phase modulation, and LFM is a type of frequency modulation. CPM and LFM are modulation methods that transmit information by changing the phase or frequency of the carrier. In other words, the amplitude of the carrier signal does not carry information. Therefore, both CPM and LFM are modulation methods that can maintain a constant amplitude and continuous phase.

[0023] In the solution provided by this application, modulating the third symbol sequence using CPM or LFM can make the phase of the second symbol sequence continuous, and further make the phase of the main signal of the first OFDM baseband signal continuous; and by designing the third symbol sequence, the second symbol sequence is made to satisfy phase self - cycling at the beginning and end, and further make the CP of the first OFDM baseband signal continuous with the phase of the signal main body. In this way, a constant - envelope waveform with constant amplitude and continuous phase can be obtained.

[0024] It should be noted that various modulation techniques such as minimum shift keying (MSK), Gaussian minimum shift keying (GMSK), and continuous phase frequency shift keying (CP - FSK) all originate from CPM, so they can all be considered as a type of CPM and should fall within the protection scope of this application.

[0025] It should be understood that CPM and LFM, as two possible modulation methods, should not impose any limitations on this application. Those skilled in the art of this application can also, based on the same concept, use other phase or frequency modulation methods to modulate the third symbol sequence to obtain a waveform with continuous phase and constant amplitude.

[0026] Combined with the first aspect, in some possible implementation manners of the first aspect, M is a positive integer, and the positions of the M extended symbols in the third symbol sequence are: before the N symbols to be transmitted, or after the N symbols to be transmitted, or continuously or discretely distributed among the N symbols to be transmitted.

[0027] Among them, the M extended symbols being before the N symbols to be transmitted or after the N symbols to be transmitted means that, while keeping the N symbols to be transmitted unchanged as a whole, M extended symbols are inserted before its starting position or after its ending position. For example, assume the N symbols to be transmitted are: a 1 , ……, a N , and the M extended symbols include: a N+1 , ……a N+M . If the M extended symbols are before the N symbols to be transmitted, the corresponding third symbol sequence is {a N+1 , ……, a N+M , a 1 , ……, a N}; if the M extended symbols are after the N symbols to be transmitted, the corresponding third symbol sequence is {a 1 , a 2 , ……, a N , a N+1 , ……, aN+M}。

[0028] The M extended symbols are distributed discretely or continuously among the N symbols to be transmitted, which means that the M extended symbols are inserted into the N symbols to be transmitted. In this case, the N symbols to be transmitted are not continuous but are filled with one or more extended symbols. For example, assume that the N symbols to be transmitted are, in sequence: a 1 , ……, a N , and the M extended symbols include: a N+1 , ……, a N+M . An example of the third symbol sequence in which the M extended symbols are continuously distributed among the N symbols to be transmitted is: {a 1 , a N+1 , …… a N+M , a 2 , ……, a N}; An example of the third symbol sequence in which the M extended symbols are discretely distributed among the N symbols to be transmitted is: {a 1 , a N+1 , a 2 , ……, a N+2 , ……, a N+M , a N [[ID=34}}.

[0029] In summary, there are various ways for the M extended symbols to be positioned in the third symbol sequence in this application.

[0030] Combined with the first aspect, in some possible implementation manners of the first aspect, obtaining the second symbol sequence based on the first symbol sequence includes: determining a third symbol sequence based on the first symbol sequence; generating (N + M) modulation symbols based on the third symbol sequence; and mapping the (N + M) modulation symbols to the REs to obtain the second symbol sequence.

[0031] Among them, the third symbol sequence can be calculated based on the N symbols to be transmitted in the first symbol sequence and the foregoing constraint conditions.

[0032] (N + M) modulation symbols can be obtained based on the modulation of the third symbol sequence. Various possible implementation manners of generating (N + M) modulation symbols based on the third symbol sequence are exemplarily shown below.

[0033] The first possible implementation manner of generating (N + M) modulation symbols based on the third symbol sequence is to modulate the third symbol sequence to obtain (N + M) modulation symbols. That is, directly modulating the third symbol sequence, the obtained (N + M) modulation symbols are phase - continuous.

[0034] A second possible implementation of generating the second symbol sequence based on the third symbol sequence is to modulate the N symbols to be transmitted and the M extended symbols in the third symbol sequence respectively to obtain N modulated symbols and M modulated symbols; according to the positions of the M extended symbols in the third symbol sequence, insert the M modulated symbols into the N modulated symbols, and perform phase adjustment on at least some of the N modulated symbols to obtain (M + N) modulated symbols with continuous phases. The difference between the above two possible implementations is that the first implementation modulates the entire third symbol sequence, while the second implementation modulates the N symbols to be transmitted and the M modulated symbols separately and then splices them. The two implementations are equivalent, only the implementation processes are different.

[0035] It should be understood that the implementation methods of generating (N + M) modulated symbols based on the third symbol sequence are not limited to the above two. For example, the third symbol sequence can be split into more subsequences, and after modulating each subsequence to obtain a modulated symbol sequence respectively, according to the positions of each subsequence in the third symbol sequence, splice the modulated symbol sequences corresponding to each subsequence into a whole and perform phase adjustment, and (N + M) modulated symbols with continuous phases can also be obtained. Mapping the (N + M) modulated symbols onto the REs can determine the values mapped to each RE.

[0036] A possible implementation of mapping the (N + M) modulated symbols onto the REs: Sampling the (N + M) modulated symbols in the fourth symbol sequence at a sampling rate of S (S is a positive integer) to obtain (N + M)×S time-domain samples, and converting the (N + M)×S time-domain samples to the frequency domain to obtain (N + M)×S frequency-domain samples. Performing RE mapping on the (N + M)×S frequency-domain samples can determine the frequency-domain samples mapped to each RE. Each frequency-domain sample can be mapped to one RE, that is, each frequency-domain sample can be mapped to one subcarrier. Therefore, the value mapped to each RE is the value of the frequency-domain sample corresponding to this RE. Thus, the frequency-domain samples mapped to (N + M)×S REs can be obtained. In other words, one manifestation of this second symbol sequence is (N + M)×S frequency-domain samples, and every S frequency-domain samples correspond to one of the (N + M) modulated symbols in the fourth symbol sequence.

[0037] Another possible implementation of mapping the (N + M) modulated symbols onto the REs is: Sampling the (N + M) modulated symbols in the fourth symbol sequence at a sampling rate of S (S is a positive integer) to obtain (N + M)×S time-domain samples, and performing time-domain periodic extension on the (N + M)×S time-domain samples to obtain (N + M)×S×Z p time-domain samples, where Z pis a positive integer, representing the number of periodic repetitions obtained after time-domain periodic extension, with (N + M) × S time-domain samples as one period. In other words, it is the number of times the (N + M) × S time-domain samples repeat. The (N + M) × S × Z p time-domain samples are transformed to the frequency domain, and (N + M) × S × Z p frequency-domain samples can be obtained. By performing RE mapping on the (N + M) × S × Z p frequency-domain samples, the frequency-domain samples mapped to each RE can be determined. Each frequency-domain sample can be mapped to one RE, that is, each frequency-domain sample can be mapped to one subcarrier. Therefore, the value mapped to each RE is the value of the frequency-domain sample corresponding to that RE. Thus, the frequency-domain samples mapped to (N + M) × S × Z p REs can be obtained. In other words, one form of representation of this second symbol sequence is (N + M) × S × Z p frequency-domain samples, and every S frequency-domain samples within each period correspond to one modulation symbol among the (N + M) modulation symbols in the fourth symbol sequence.

[0038] In a second aspect, a communication method is provided. This method can be applied to a communication device, which can be a communication equipment (such as a terminal device or a network device), or it can also be a component for this communication equipment (such as a baseband chip, a chip system, a processor, etc.), or it can also be a logic module or software that can implement all or part of the functions of this communication equipment, etc. This application does not make any limitations in this regard.

[0039] Exemplarily, the method includes: obtaining a first symbol sequence, where the first symbol sequence includes N symbols to be transmitted, and N is a positive integer; based on the first symbol sequence, generating a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence, where the first CP sequence is K 1 symbols at the end of the fourth symbol sequence. The symbols in the fourth symbol sequence are (N + M) modulation symbols obtained by modulating a third symbol sequence. The third symbol sequence includes the N symbols to be transmitted in the first symbol sequence and M extended symbols. The M extended symbols make the phase of the fourth symbol sequence obtained by the modulation continuous, and the phase difference between the starting position and the ending position is an integer multiple of 2π. M is an integer greater than or equal to zero. Based on the fourth symbol sequence and the first CP sequence, generating a first OFDM baseband signal, and the time-domain resource of this first OFDM baseband signal is one OFDM symbol.

[0040] Among them, for the content such as the first symbol sequence, the third symbol sequence, the fourth symbol sequence, modulation, phase continuity, and the phase difference between the phase at the starting position and the phase at the ending position being an integer multiple of 2π, reference can be made to the relevant descriptions in the first aspect, and details will not be elaborated here.

[0041] Different from the first aspect, in the method provided by the second aspect, a first CP sequence for generating the first CP can be pre-generated, and the fourth symbol sequence and the first CP sequence can be jointly used to generate the first OFDM baseband signal. In this case, after the signal body of the first OFDM baseband signal is generated, it is not necessary to copy some symbols at the end of the signal body to before its head to generate the first CP. That is to say, the second aspect provides a way to generate the OFDM baseband signal different from the first aspect.

[0042] Since the first CP sequence is the last K 1 symbols of the fourth symbol sequence, and the fourth symbol sequence is phase continuous and satisfies phase self - circulation at the head and tail. Therefore, if the first CP sequence is located before the fourth symbol sequence, the phase at the end position of the first CP sequence and the phase at the starting position of the fourth symbol sequence can be continuous. The first OFDM baseband signal generated based on the fourth symbol sequence and the first CP sequence is also phase continuous.

[0043] Based on the above - mentioned technical solution, by expanding the first symbol sequence to obtain the third symbol sequence, and then modulating the third symbol sequence to obtain the fourth symbol sequence, it can simultaneously satisfy: being phase continuous, having phase self - circulation at the head and tail, and the phase at the end position of the first CP sequence and the phase at the starting position of the fourth symbol sequence being continuous. The first OFDM baseband signal generated based on the fourth symbol sequence and the first CP sequence also satisfies phase continuity. On this basis, if the modulation technique adopted is a modulation technique that can keep the amplitude constant, a waveform with continuous phase and constant envelope can be obtained. In this way, a scheme of combining phase or frequency modulation technology and OFDM technology to obtain a constant - envelope waveform can be realized. Since the constant - envelope waveform meets the requirements of the waveform for direct frequency conversion and non - linear power amplification, the communication device can use some more power - saving ways to transmit signals. In addition, further, for communication devices (especially IoT nodes with small volume and no large - capacity battery), their standby life can be improved.

[0044] Combined with the second aspect, in some possible implementation manners of the second aspect, the modulation includes CPM or LFM.

[0045] For the detailed content of CPM and LFM, reference can be made to the relevant descriptions of CPM or LFM in the first aspect above, and details will not be elaborated here.

[0046] In combination with the second aspect, in some possible implementation manners of the second aspect, M is a positive integer, and the positions of the M extended symbols in the third symbol sequence are as follows: before the N symbols to be transmitted, or after the N symbols to be transmitted, or continuously or discretely distributed among the N symbols to be transmitted.

[0047] For the detailed content of the positions of the M extended symbols in the third symbol sequence, reference may be made to the relevant description of the positions of the M extended symbols in the third symbol sequence in the first aspect above, which will not be elaborated here.

[0048] In combination with the second aspect, in some possible implementation manners of the second aspect, generating a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence based on the first symbol sequence includes: determining a third symbol sequence based on the first symbol sequence; generating a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence based on the third symbol sequence.

[0049] Among them, the third symbol sequence can be calculated based on the N symbols to be transmitted in the first symbol sequence and the foregoing constraint conditions.

[0050] Furthermore, the following exemplarily shows various possible implementation manners of generating a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence based on the third symbol sequence.

[0051] The first possible implementation manner of generating a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence based on the third symbol sequence is to modulate the third symbol sequence to obtain the fourth symbol sequence; add the K 1 modulated symbols at the end of the fourth symbol sequence to before the fourth symbol sequence to obtain the fourth symbol sequence and the first CP sequence located before the fourth symbol sequence.

[0052] That is to say, after modulating the third symbol sequence to obtain the fourth symbol sequence, then use the K 1 modulated symbols at the end of the fourth symbol sequence as the first CP sequence and add them to before the fourth symbol sequence.

[0053] The second possible implementation manner of generating a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence based on the third symbol sequence is to add the K 1 symbols at the end of the third symbol sequence to before the third symbol sequence to obtain a fifth symbol sequence; modulate the fifth symbol sequence to obtain the fourth symbol sequence and the first CP sequence located before the fourth symbol sequence. Among them, the K 1 symbols at the end of the third symbol sequence are the symbols used to generate the first CP sequence.

[0054] That is to say, after adding symbols that can be used to generate the first CP sequence to the third symbol sequence, modulation is then performed. It should be noted that in this implementation manner, the fourth symbol sequence and the first CP sequence are modulated and generated as a whole through the fifth symbol sequence, so as to ensure phase continuity between the modulated fifth symbol sequence and the first CP sequence. Among them, the fourth symbol sequence is the modulated symbol corresponding to the third symbol sequence after modulation, and the first CP sequence is the modulated symbol corresponding to the K 1 symbols at the end of the third symbol sequence after modulation. Therefore, it can also be said that the fourth symbol sequence is obtained based on the modulation of the third symbol sequence.

[0055] A third possible implementation manner for generating the fourth symbol sequence and the first CP sequence located before the fourth symbol sequence based on the third symbol sequence is to separately modulate the N symbols to be transmitted and the M extended symbols in the third symbol sequence to obtain N modulated symbols and M modulated symbols; according to the positions of the M extended symbols in the third symbol sequence, insert the M modulated symbols into the N modulated symbols, and perform phase adjustment on at least some of the N modulated symbols so that the phases of the (M + N) modulated symbols after inserting the M modulated symbols are continuous; add the K 1 modulated symbols at the end of the (M + N) modulated symbols before the (M + N) modulated symbols to obtain the fourth symbol sequence and the first CP sequence located before the fourth symbol sequence.

[0056] Among them, the (M + N) modulated symbols are the fourth symbol sequence. In this implementation manner, the N symbols to be transmitted and the M modulated symbols are modulated separately, and after obtaining the fourth symbol sequence, the first CP sequence is added. Since the third symbol sequence includes N symbols to be transmitted and M modulated symbols, modulating the N symbols to be transmitted and the M modulated symbols separately and then splicing them is equivalent to modulating the third symbol sequence as a whole, only the implementation processes are different.

[0057] Through the above method, an OFDM baseband signal with continuous phase on one OFDM symbol can be obtained. Since the first communication device may also transmit data on multiple consecutive OFDM symbols, the first OFDM baseband signal can be further designed to obtain continuous phase between OFDM symbols. For the convenience of understanding, the second OFDM baseband signal is introduced in the following text for description.

[0058] In combination with the second aspect, in some possible implementation manners of the second aspect, the difference between the phase at the starting position of the first OFDM baseband signal and the phase at the ending position of the second OFDM baseband signal is an integer multiple of 2π. The time-domain resource of the second OFDM baseband signal is adjacent to the time-domain resource of the first OFDM baseband signal, and the time-domain resource of the second OFDM baseband signal is before the time-domain resource of the first OFDM baseband signal. The time-domain resource of the second OFDM baseband signal is one OFDM symbol.

[0059] That is to say, the second OFDM baseband signal is a signal transmitted on one OFDM symbol scheduled before the OFDM symbol of the first OFDM baseband signal. Or, the time-domain resource of the first OFDM baseband signal is the first OFDM symbol, the time-domain resource of the second OFDM baseband signal is the second OFDM symbol. The second OFDM symbol is adjacent to the first OFDM symbol, and the second OFDM symbol is before the first OFDM symbol.

[0060] The second OFDM baseband signal may be a signal generated based on the method provided in this application, or may be a signal generated based on existing OFDM technologies. This application does not make any limitations in this regard.

[0061] In order to make the phases of the first OFDM baseband signal and the second OFDM baseband signal continuous, a possible design is to perform phase compensation on the first OFDM baseband signal so that the difference between the phase at its starting position and the phase at the ending position of the second OFDM baseband signal is an integer multiple of 2π. Or, perform phase compensation on the phase of the OFDM baseband signal on the latter OFDM symbol so that the difference between the phase at its starting position and the phase at the ending position of the OFDM baseband signal on the previous OFDM symbol is an integer multiple of 2π.

[0062] Exemplarily, assume that the phase at the ending position of the second OFDM baseband signal is denoted as The starting phase of the first OFDM baseband signal before phase compensation is Then the phase compensation amount Satisfies: k 1 Is an integer.

[0063] Based on the aforementioned second implementation manner of generating the fourth symbol sequence and the first CP sequence before the fourth symbol sequence based on the third symbol sequence, a possible implementation manner of performing phase compensation on the first OFDM baseband signal is to adjust the initial phase of modulation so that the adjusted initial phase And the initial phase before adjustment Satisfies:

[0064] Based on the foregoing various implementation manners of generating a fourth symbol sequence and a first CP sequence before the fourth symbol sequence based on the third symbol sequence, a possible implementation manner of performing phase compensation on the first OFDM baseband signal is based on the foregoing phase compensation amount. Perform phase compensation on each modulation symbol in the generated fourth symbol sequence and the first CP sequence. The fourth symbol sequence and the first CP sequence used to generate the first OFDM baseband signal are the fourth symbol sequence after phase compensation and the first CP sequence after phase compensation.

[0065] In order to make the signal phases continuous on different OFDM symbols, another possible design is to add extended symbols and symbols for generating their respective CP sequences to the symbol sequences scheduled to be transmitted on a plurality of consecutive OFDM symbols respectively, and then splice them into a symbol sequence in the chronological order of the OFDM symbols, and modulate the spliced symbol sequence to obtain a modulation symbol sequence and a CP sequence corresponding to each OFDM symbol. Thus, the phases of the OFDM baseband signals on each OFDM symbol are continuous.

[0066] Combined with the first aspect or the second aspect, in some possible implementation manners, the modulation is CPM, and M satisfies: 1≤M≤max{U + 2, U + V - 1}; where, V satisfies: h = W / V, and W / V is in the simplest fraction, h is the modulation index of the CPM, U is a predefined value, and W, U, and V are positive integers.

[0067] Combined with the first aspect or the second aspect, in some possible implementation manners, the modulation is LFM, and M satisfies: 1≤M≤3.

[0068] Since different numbers M of the extended symbols may bring different spectral efficiencies and different degrees of spectral leakage. An overly large M may result in too low a frequency efficiency, but with small spectral leakage; an overly small M may bring a relatively high spectral efficiency, but cause relatively large spectral leakage. Therefore, by restricting the value range of M, a trade-off can be obtained between spectral efficiency and spectral leakage.

[0069] It should be noted that the frequency modulation signal obtained by LFM is a chirp signal, so it can be regarded as the case of U = 1 and V = 1. In other words, when the modulation method is LFM, it can also be considered that M satisfies: 1≤M≤max{U + 2, U + V - 1} and is an integer.

[0070] In combination with the first aspect or the second aspect, in some possible implementations, the time-domain resources of the first OFDM baseband signal are adjacent to the time-domain resources of the second OFDM baseband signal, and the time-domain resources of the second OFDM baseband signal are before the time-domain resources of the first OFDM baseband signal. The time-domain resources of the second OFDM baseband signal are one OFDM symbol. The second OFDM baseband signal is generated based on a fifth symbol sequence, and the fifth symbol sequence is modulated based on a sixth symbol sequence. The sixth symbol sequence includes P symbols to be transmitted and Q extended symbols. Q 1 of the Q extended symbols are among the first (P + Q - K 2 ) symbols in the sixth symbol sequence, and Q 2 of the Q extended symbols are among the last K 2 symbols in the sixth symbol sequence, and it satisfies that if the modulation is performed on the first (P + Q - K 2 ) symbols, the phase difference between the end position and the start position of the obtained modulated symbol sequence is an integer multiple of 2π, and if the modulation is performed on the last K 2 symbols, the phase difference between the end position and the start position of the obtained modulated symbol sequence is also an integer multiple of 2π. Wherein, P is a positive integer, Q, Q 1 and Q 2 are all integers greater than or equal to 0, and K 2 is an integer greater than 1. And M is an integer greater than or equal to 0. M 1 of the M extended symbols are among the first (N + M - K 1 ) symbols in the third symbol sequence, and M 2 of the M extended symbols are among the last K 1 symbols in the third symbol sequence, and it satisfies that if the modulation is performed on the first (N + M - K 1 ) symbols, the phase difference between the end position and the start position of the obtained modulated symbol sequence is an integer multiple of 2π, and the difference between the initial phase of the modulation of the first OFDM baseband signal and the initial phase of the modulation of the second OFDM baseband signal is an integer multiple of 2π. Wherein, M = M 1 + M 2 , M 1 , M 2 are all integers greater than or equal to 0, and K 1 is an integer greater than 1.

[0071] That is to say, when the second OFDM baseband signal and the first OFDM baseband signal simultaneously meet their respective constraint conditions, the phase continuity between OFDM symbols can be obtained by controlling the initial phase.

[0072] Among them, the second OFDM baseband signal can also be generated based on the method for generating the first OFDM baseband signal provided in the foregoing first aspect or second aspect. The fifth symbol sequence can correspond to the fourth symbol sequence in the first aspect or the second aspect.

[0073] Taking the first OFDM baseband signal as an example, M extended symbols are discretely distributed in the third symbol sequence. If the third symbol sequence is divided into two parts, one part includes the symbols for generating the first CP, and the remaining symbols are the other part. Each of the M extended symbols includes at least one extended symbol in each part. And due to the presence of one or more extended symbols in each part, after modulating the third symbol sequence, each part can satisfy the head and tail phase self - cycle.

[0074] It can be understood that among the third symbol sequence, the latter K 1 symbols are the symbols for generating the first CP, which is one part of the above two parts, and the first (N + M - K 1 ) symbols are the other part. Since the first (N + M - K 1 ) symbols are modulated, the difference between the phase of the end position and the phase of the start position of the obtained modulated symbol sequence (that is, including (N + M - K 1 ) modulated symbols) is an integer multiple of 2π. Also, because CPM has the characteristic of accumulating its own phase, each modulated symbol obtained by LFM will return to the initial phase. Therefore, in the fourth symbol sequence obtained by performing CPM or LFM on the third symbol sequence, the phase of the end position of the first (N + M - K 1 ) modulated symbols in the first part is continuous with the phase of the start position of the latter K 1 modulated symbols in the second part. From this, it can be obtained that the difference between the phase of the start position of the latter K 1 modulated symbols and the phase of the start position of the first (N + M - K 1 ) modulated symbols in the first part is also an integer multiple of 2π. That is, after dividing the third symbol sequence into two parts, each part satisfies the head and tail phase self - cycle respectively. This characteristic can be called double head and tail phase self - cycle.

[0075] Similar to the first OFDM baseband signal, Q extended symbols are discretely distributed in the sixth symbol sequence. If the sixth symbol sequence is divided into two parts, one part includes the symbols for generating the second CP, and the remaining symbols are the other part. Among them, the second CP is the CP of the second OFDM baseband signal. In the sixth symbol sequence, the symbols for generating the second CP are the latter K 2 symbols at the end of the sixth symbol sequence. The latter K 2 symbols at the end of the sixth symbol sequence can be modulated to obtain the latter K 2Q modulation symbols. The Q extended symbols each include at least one extended symbol in each section. Due to the presence of one or more extended symbols in each section, after modulating the sixth symbol sequence, each section can satisfy the head and tail phase self - circulation.

[0076] The time - domain resources of the first OFDM baseband signal are located after the time - domain resources of the second OFDM baseband signal. Assuming that the second OFDM baseband signal is generated based on the fifth symbol sequence, that is, it is necessary to ensure that the phase difference between the phase at the start position of the K 1 modulation symbols at the end of the fourth symbol sequence and the phase at the end position of the modulation symbols of the CP (hereinafter referred to as the second CP) used to generate the second OFDM baseband signal is an integer multiple of 2π, and the phase difference between the phase at the end position of the K 2 modulation symbols used to generate the second CP and the phase at the start position of the fifth symbol sequence is an integer multiple of 2π. Therefore, as long as it is ensured that the phase difference between the phase at the start position of the above - mentioned K 1 modulation symbols and the phase at the start position of the fifth symbol sequence is an integer multiple of 2π, that is, as long as it is ensured that the phase difference between the phase at the start position of the fourth symbol sequence and the phase at the start position of the fifth symbol sequence is an integer multiple of 2π.

[0077] Since the phases at the start positions of the fourth symbol sequence and the fifth symbol sequence can both be controlled by the initial phase of modulation, therefore, by controlling the phase difference between the two to be an integer multiple of 2π, the phase continuity between the first OFDM baseband signal and the second OFDM baseband signal can be achieved.

[0078] Furthermore, through the following possible implementation methods, it is possible to further obtain a compromise between spectral efficiency and spectral leakage while satisfying the double head - and - tail phase self - circulation.

[0079] Optionally, the modulation is CPM, and M 1 satisfies: 1 ≤ M 1 ≤ max{U + 2, U + V - 1} and is an integer, M 2 satisfies: 1 ≤ M 2 ≤ max{U + 2, U + V - 1} and is an integer, M satisfies: 2 ≤ M ≤ 2×max{U + 2, U + V - 1}, and is an integer; Q 1 satisfies: 1 ≤ Q 1 ≤ max{U + 2, U + V - 1} and is an integer, Q 2 satisfies: 1 ≤ Q 2 ≤ max{U + 2, U + V - 1} and is an integer, Q satisfies: 2 ≤ Q ≤ 2×max{U + 2, U + V - 1}, and is an integer.

[0080] Optionally, the modulation method is LFM, and M 1Satisfy: 1 ≤ M 1 ≤ 3 and is an integer, M 2 Satisfy: 1 ≤ M 2 ≤ 3 and is an integer, M satisfies: 2 ≤ M ≤ 6; Q 1 Satisfy: 1 ≤ Q 1 ≤ 3 and is an integer, Q 2 Satisfy: 1 ≤ Q 2 ≤ 3 and is an integer, Q satisfies: 2 ≤ Q ≤ 6.

[0081] It can be seen that the value range of M in the above text is obtained by superimposing the ranges of M 1 and M 2 , and the value range of Q is obtained by superimposing the ranges of Q 1 and Q 2 , while the ranges of M 1 , M 2 , Q 1 and Q 2 are respectively determined based on the ranges [1, max{U + 2, U + V - 1}] and [1, 3] provided in the previous text.

[0082] In another design, the value ranges of M and Q can also be directly defined as: 1 ≤ M ≤ max{U + 2, U + V - 1}, and is an integer; 1 ≤ Q ≤ max{U + 2, U + V - 1}, and is an integer.

[0083] Combined with the first aspect or the second aspect, in some possible implementation manners, the method further includes: sending a first OFDM baseband signal.

[0084] As described above, in the method provided in the first aspect or the second aspect, the first communication device can be a communication device such as a terminal device, a network device, etc., or a component configured in a communication device, such as a baseband chip, a chip system, a processor, etc.

[0085] For a baseband chip for implementing the method in the first aspect or the second aspect or a chip system, a processor, etc. for implementing baseband processing functions, the sending of the first OFDM baseband signal includes: outputting the first OFDM baseband signal.

[0086] Outputting the first OFDM baseband signal can specifically refer to the communication between interfaces inside the communication device of the first OFDM baseband signal, for example, output by the baseband chip and input to the radio frequency chip, so as to facilitate the radio frequency segment processing and signal transmission of the communication device.

[0087] For a communication device for implementing the method in the first aspect or the second aspect, or a chip system for the communication device, the sending of the first OFDM baseband signal includes: outputting a bandpass signal based on the first OFDM baseband signal; performing power amplification on the bandpass signal to obtain a power-amplified bandpass signal; and sending the power-amplified bandpass signal.

[0088] That is to say, the first OFDM baseband signal can be processed such as up-conversion and power amplification to obtain a power-amplified bandpass signal, and then be sent out through an antenna. In other words, the first OFDM baseband signal is carried on the power-amplified bandpass signal and sent out.

[0089] Combined with the first aspect or the second aspect, in some possible implementation manners, the method further includes: sending a reference signal, where the time-domain resource of the reference signal is one or more OFDM symbols, and the time-domain resource of the reference signal is different from the time-domain resource of the first OFDM baseband signal.

[0090] In order to ensure that (N + M) modulated symbols can be normally demodulated to obtain the first symbol sequence, and considering the requirements of channel measurement, the first communication device also needs to send a reference signal. In order not to destroy the characteristic of phase continuity, the first communication device cannot insert a reference signal at a specific frequency-domain position, so a time-domain reference signal is adopted, and the reference signal is carried on one or more OFDM symbols for transmission.

[0091] The time-domain resource of the reference signal is different from the time-domain resource of the first OFDM baseband signal. In other words, the time-domain resource of the reference signal is different from the time-domain resource of the data signal. For example, if the time-domain resource of the first OFDM baseband signal is one OFDM symbol, the time-domain resource of the reference signal can be one or more OFDM symbols adjacent to the OFDM symbol.

[0092] Optionally, the bandwidth covered by the frequency-domain resource of the reference signal and the frequency-domain resource of the first OFDM baseband signal overlap at least partially.

[0093] It should be understood that the signal body of the first OFDM baseband signal and the CP occupy the same frequency-domain resource. Therefore, the frequency-domain resource of the first OFDM baseband signal is also the frequency-domain resource of the second symbol sequence described in the first aspect, that is, the subcarriers corresponding through RE mapping.

[0094] There may be the following possible situations where the frequency band covered by the frequency-domain resource of the reference signal overlaps with the target frequency band: the frequency-domain resource of the reference signal overlaps with the frequency-domain resource of the first OFDM baseband signal, or the frequency-domain resource of the reference signal does not overlap with the frequency-domain resource of the first OFDM baseband signal, but the frequency bands covered by the two overlap.

[0095] The frequency band covered by the frequency-domain resource can be understood as follows: If the frequency-domain resource is continuous, the frequency band covered by the frequency-domain resource is the frequency band occupied by the frequency-domain resource; if the frequency-domain resource is discontinuous, such as in a comb shape, the frequency band covered by the frequency-domain resource can be the frequency band from the first subcarrier to the last subcarrier of the frequency-domain resource.

[0096] The bandwidth covered by the frequency-domain resource of the reference signal at least partially overlaps with the bandwidth covered by the frequency-domain resource of the first OFDM baseband signal, which can make the estimation and measurement of the channel based on the reference signal more accurate and is more conducive to the correct demodulation of the first OFDM baseband signal.

[0097] A possible design is that the frequency-domain resource of the reference signal is the same as the frequency-domain resource of the first OFDM baseband signal.

[0098] That is to say, the frequency-domain resource of the reference signal and the frequency-domain resource of the first OFDM baseband signal are in the same position and have the same size, and the two completely overlap. Thus, a full-channel measurement of the frequency-domain resource used to transmit the first OFDM baseband signal can be obtained, which is more conducive to the correct demodulation of the second symbol sequence.

[0099] Exemplarily, the first communication device is a terminal device, and the reference signal is an uplink reference signal.

[0100] Exemplarily, the first communication device is a network device, and the reference signal is a downlink reference signal.

[0101] In a third aspect, a communication method is provided. This method can be applied to a second communication device. The second communication device can be a communication device (such as a terminal device or a network device), or it can also be a component configured in the communication device (such as a baseband chip, a chip system, a processor, etc.), or it can also be a logic module or software that can implement all or part of the functions of the communication device, etc. This application does not make any limitations in this regard.

[0102] The second communication device can be a device that communicates with the first communication device in the first aspect or the second aspect. For example, if the first communication device is a terminal device, the second communication device is also a terminal device; or if the first communication device is a terminal device, the second communication device is a network device.

[0103] Exemplarily, the method includes: obtaining a first OFDM baseband signal, where the time domain resource of the first OFDM baseband signal is one OFDM symbol; obtaining a fourth symbol sequence based on the first OFDM baseband signal, where the fourth symbol sequence includes L modulated symbols, and L is a positive integer; demodulating the fourth symbol sequence to obtain a third symbol sequence, where the third symbol sequence includes N first symbols and M extended symbols, L = M + N, N is a positive integer less than or equal to L, and M is an integer greater than or equal to zero; determining the positions of the M extended symbols in the third symbol sequence and the value of M; and obtaining the N first symbols from the third symbol sequence.

[0104] It should be understood that the N first symbols in the third aspect may correspond to the N symbols to be transmitted in the first aspect or the second aspect. Since the symbols to be transmitted are relative to the device acting as the transmitter, for the device acting as the receiver, the received symbols are already the symbols that have been transmitted, so they are distinguished and named as the first symbols.

[0105] Corresponding to the processing procedures in the first aspect or the second aspect, the first OFDM baseband signal may be the baseband signal obtained after processing such as down-conversion of the band-pass signal received by the second communication device from the first communication device. A fourth symbol sequence can be obtained based on the first OFDM baseband signal. The fourth symbol sequence may include L (i.e., (M + N)) modulated symbols. After demodulating the L modulated symbols, a third symbol sequence including N first symbols and M extended symbols can be obtained. The second communication device can remove the M extended symbols from the third symbol sequence according to M and the positions of the M extended symbols in the third symbol sequence, so as to obtain N first symbols. The symbol sequence composed of the N first symbols may correspond to the first symbol sequence in the first aspect.

[0106] Based on the above technical solutions, although the first communication device expands the first symbol sequence to be transmitted and modulates it after adding M extended symbols to obtain a third symbol sequence, after the second communication device obtains the fourth symbol sequence from the first OFDM baseband signal, it can still obtain N first symbols from the third symbol sequence according to the positions of the M extended symbols in the third symbol sequence and the value of M. Therefore, the addition of the M extended symbols does not affect the correct demodulation of the first OFDM baseband signal. And from the perspective of the first communication device, due to the addition of the M extended symbols, the phase of the fourth symbol sequence is continuous and satisfies the head-to-tail phase self-circulation, thereby making the phase of the first OFDM baseband signal continuous, which is beneficial for the first communication device to obtain a waveform with continuous phase and constant envelope, and also provides strong support for the first communication device to transmit signals in a more power-saving manner, thus being beneficial to improving the standby life of the first communication device.

[0107] In combination with the third aspect, in some possible implementation manners of the third aspect, the demodulation includes: CPM demodulation or LFM demodulation.

[0108] The manner in which the second communication device demodulates the fourth symbol sequence corresponds to the manner in which the first communication device modulates the third symbol sequence. The first communication device and the second communication device may pre-negotiate the modulation and demodulation manners, or the modulation and demodulation manners may be predefined by the protocol.

[0109] It should also be understood that the demodulation of the fourth symbol sequence may be CPM demodulation or LFM demodulation corresponding to the first aspect or the second aspect, but is not limited to CPM demodulation or LFM demodulation. Those skilled in the art can make simple transformations based on the same concept to achieve the same effect as CPM demodulation or LFM demodulation. For example, taking CPM demodulation as an example, the demodulation in the phase domain is converted to other domains for execution and then converted back to the phase domain after demodulation is completed. In essence, CPM demodulation is still completed. Such cases will not be elaborated here.

[0110] One possible case is that M is zero; another possible case is that M is a positive integer.

[0111] In the case where M is zero, the second communication device can directly obtain N first symbols from the third symbol sequence. At this time, the positions of the M extended symbols in the third symbol sequence may not be considered, or it can be said that it is determined that the M extended symbols do not exist in the third symbol sequence. In the case where M is a positive integer, the second communication device can obtain N first symbols from the third symbol sequence in combination with the positions of the M extended symbols in the third symbol sequence.

[0112] In combination with the third aspect, in some possible implementation manners of the third aspect, the positions of the M extended symbols in the third symbol sequence are: before the N first symbols, or after the N first symbols, or continuously or discretely distributed among the N first symbols.

[0113] For the detailed content of the positions of the M extended symbols in the third symbol sequence, reference can be made to the relevant descriptions regarding the positions of the M extended symbols in the third symbol sequence in combination with the first aspect, and no further elaboration will be provided.

[0114] In combination with the third aspect, in some possible implementation manners, the demodulation is CPM demodulation, and M satisfies: 1 ≤ M ≤ max{U + 2, U + V - 1}, or 2 ≤ M ≤ 2 × max{U + 2, U + V - 1}; where V satisfies: h = W / V, and W / V is the simplest fraction, h is the modulation index of the CPM, U is a predefined value, and W, U, and V are positive integers.

[0115] In combination with the third aspect, in some possible implementation manners, the demodulation is LFM demodulation, and M satisfies: 1 ≤ M ≤ 3, or, 2 ≤ M ≤ 6.

[0116] For the description of the value range of M, reference may be made to the description in combination with the first aspect or the second aspect, which will not be elaborated here.

[0117] In the method provided in the third aspect, the second communication device may be a communication device such as a terminal device or a network device. The method in the third aspect may be executed by the second communication device or by components in the second communication device, such as a baseband chip, a chip system, a processor, etc.

[0118] For a baseband chip for implementing the method in the third aspect or a chip system, a processor, etc. for implementing the baseband processing function, optionally, the obtaining of the first OFDM baseband signal includes: the second communication device receives the first OFDM baseband signal. For example, the second communication device receives the first OFDM baseband signal from other chip systems or processors in the communication device to which the second communication device belongs. For example, the other chip systems include: a radio frequency chip in the communication device to which the second communication device belongs.

[0119] For the second communication device, the obtaining of the first OFDM baseband signal includes: receiving a bandpass signal from the first communication device; and obtaining the first OFDM baseband signal based on the bandpass signal.

[0120] The bandpass signal received by the second communication device may be the power-amplified bandpass signal sent by the first communication device in the first aspect or the second aspect. Corresponding to the processing of the first communication device in the first aspect or the second aspect, after receiving the bandpass signal, the first communication device may perform down-conversion and other processing to obtain the first OFDM baseband signal.

[0121] In combination with the third aspect, in some possible implementation manners of the third aspect, the method further includes: receiving a reference signal, where the time-domain resource of the reference signal is one or more OFDM symbols, and the time-domain resource of the reference signal is different from the time-domain resource of the first OFDM baseband signal.

[0122] In this application, in order not to destroy the characteristic of phase continuity, the first communication device may transmit the reference signal carried on one or more OFDM symbols. The second communication device may receive the reference signal on the one or more OFDM symbols for signal demodulation or channel measurement. For the detailed content of the time-domain resource of the reference signal, reference may be made to the relevant description of the time-domain resource of the reference signal in the first aspect or the second aspect above, which will not be elaborated.

[0123] Optionally, the bandwidth covered by the frequency-domain resources of the reference signal overlaps at least partially with the bandwidth covered by the frequency-domain resources of the first OFDM baseband signal.

[0124] In a possible design, the frequency-domain resources of the reference signal are the same as the frequency-domain resources of the first OFDM baseband signal.

[0125] For the details of the frequency-domain resources of the reference signal, refer to the relevant descriptions of the frequency-domain resources of the reference signal in the first aspect or the second aspect above, which will not be elaborated here.

[0126] Combining the first aspect to the third aspect, in some possible implementation manners, the positions of M and M extended symbols in the third symbol sequence are predefined by the protocol, or are indicated by the first communication device to the second communication device, or are indicated by the second communication device to the first communication device. Therefore, there may be signaling interaction between the first communication device and the second communication device, and this signaling can be used to carry the fifth information and / or the sixth information described below.

[0127] If the positions of M and M extended symbols in the third symbol sequence are predefined by the protocol, the second communication device can determine the positions of M and M extended symbols in the third symbol sequence according to the protocol.

[0128] If the position of M extended symbols in the third symbol sequence is indicated by the first communication device to the second communication device through the fifth information, the second communication device can determine the position of M extended symbols in the third symbol sequence according to the fifth information.

[0129] Correspondingly, the method further includes: the first communication device sends the fifth information to the second communication device, or in other words, the second communication device receives the fifth information from the first communication device, and this fifth information is used to indicate the position of M extended symbols in the third symbol sequence.

[0130] For example, the second communication device is a terminal device, the first communication device is a network device, and the position of M extended symbols in the third symbol sequence is indicated by the first communication device to the second communication device through the fifth information. In other words, the position of M extended symbols in the third symbol sequence is configured by the network device.

[0131] For another example, both the first communication device and the second communication device are terminal devices. The position of M extended symbols in the third symbol sequence is determined by the first communication device and indicated to the second communication device through the fifth information. In other words, the position of M extended symbols in the third symbol sequence is determined by the terminal device. The second communication device can determine the position of M extended symbols in the third symbol sequence according to the fifth information.

[0132] If the positions of M extended symbols in the third symbol sequence are indicated by the second communication device to the first communication device through the fifth information, the second communication device can determine the positions of the M extended symbols in the third symbol sequence by itself.

[0133] Correspondingly, the method further includes: the first communication device receives the fifth information from the second communication device, or in other words, the second communication device sends the fifth information to the first communication device, and the fifth information is used to indicate the positions of M extended symbols in the third symbol sequence.

[0134] For example, if the second communication device is a network device and the first communication device is a terminal device, the positions of M extended symbols in the third symbol sequence are configured by the second communication device for the first communication device through the fifth information, that is to say, the positions of M extended symbols in the third symbol sequence are configured by the network device. Or, if both the first communication device and the second communication device are terminal devices, the positions of M extended symbols in the third symbol sequence are determined by the second communication device and indicated to the first communication device through the fifth information, that is to say, the positions of M extended symbols in the third symbol sequence are determined by the terminal device.

[0135] Similarly, if the value of M is indicated by the first communication device to the second communication device through the sixth information, the second communication device can determine M according to the sixth information.

[0136] Correspondingly, the method further includes: the first communication device sends the sixth information to the second communication device, or in other words, the second communication device receives the sixth information from the first communication device, and the sixth information is used to indicate M.

[0137] If M is indicated by the second communication device to the first communication device through the sixth information, the second communication device can determine M by itself.

[0138] Correspondingly, the method further includes: the first communication device receives the sixth information from the second communication device, or in other words, the second communication device sends the sixth information to the first communication device, and the sixth information is used to indicate M.

[0139] For the relevant examples of the interaction of the sixth information between the first communication device and the second communication device, please refer to the example description of the interaction of the fifth information between the two parties above, and will not be repeated here.

[0140] It can be understood that any one of the positions of M and M extended symbols in the third symbol sequence can be predefined by the protocol, and the other can be indicated by the fifth information or the sixth information. Alternatively, the two positions of M and M extended symbols in the third symbol sequence can be determined by different devices or by the same device. In other words, the two items of the fifth information and the sixth information can be indicated by different devices or by the same device. If the two positions of M and M extended symbols in the third symbol sequence are indicated by the same device to another device, the above-mentioned fifth information and sixth information can be carried in the same signaling, and the sending and receiving of the fifth information and the sixth information can be combined into one step. Further, the fifth information and the sixth information can be generated by joint coding. For example, the fifth information and the sixth information can be the same cell in the same signaling; or, the fifth information and the sixth information can also be generated by independent coding. For example, the fifth information and the sixth information can be different cells in the same signaling.

[0141] As an example, M is predefined, and the positions of M extended symbols in the third symbol sequence are determined by the first communication device. Correspondingly, the above-mentioned fifth information can be the information sent by the first communication device to the second communication device, and the fifth information is used to indicate the positions of M extended symbols in the third symbol sequence. The second communication device can determine M according to the protocol and determine the positions of M extended symbols in the third symbol sequence according to the fifth information from the first communication device.

[0142] Optionally, the length of an OFDM symbol is determined by the subcarrier spacing, and the subcarrier spacing can be predefined or configured by the network device. Therefore, there may be signaling interaction between the first communication device and the second communication device, and the signaling can be used to carry the seventh information described below.

[0143] Correspondingly, optionally, the method further includes: the first communication device receives the seventh information from the second communication device, or in other words, the second communication device sends the seventh information to the first communication device, and the seventh information is used to indicate the subcarrier spacing, and the subcarrier spacing is used to determine the duration of an OFDM symbol.

[0144] For example, the first communication device is a terminal device, the second communication device is a network device or a terminal device, and the second communication device indicates the subcarrier spacing to the first communication device by sending the seventh information.

[0145] Optionally, the method further includes: the first communication device sends the seventh information to the second communication device, or in other words, the second communication device receives the seventh information from the first communication device, and the seventh information is used to indicate the subcarrier spacing, and the subcarrier spacing is used to determine the duration of an OFDM symbol.

[0146] For example, the first communication device is a network device or a terminal device, the second communication device is a terminal device, and the first communication device can indicate the subcarrier spacing to the second communication device by sending a seventh piece of information.

[0147] Optionally, the method further includes: the first communication device and the second communication device receive the seventh piece of information from a network device, and the seventh piece of information is used to indicate the subcarrier spacing.

[0148] As another example, both the first communication device and the second communication device are terminal devices, and both the first communication device and the second communication device can receive the seventh piece of information from a network device.

[0149] Combined with the first aspect to the third aspect, in some possible implementation manners, the frequency-domain resources of the first OFDM baseband signal are (N + M) × S subcarriers. That is to say, the first OFDM baseband signal is transmitted on (N + M) × S subcarriers.

[0150] Each of the (N + M) × S subcarriers can be used to transmit a frequency-domain sample point. The (N + M) × S frequency-domain sample points transmitted by the (N + M) × S subcarriers are obtained by performing a Fourier transform on (N + M) × S time-domain sample points, and the (N + M) × S time-domain sample points are obtained by sampling the (N + M) modulation symbols. S is a positive integer.

[0151] If the (N + M) modulation symbols are sampled at a sampling rate of S (S is a positive integer), (N + M) × S time-domain sample points can be obtained. By converting the (N + M) × S time-domain sample points to the frequency domain, (N + M) × S frequency-domain sample points can be obtained, and the (N + M) × S frequency-domain sample points can be mapped to (N + M) × S subcarriers.

[0152] Combined with the foregoing time-domain resources and frequency-domain resources, it can be known that the first OFDM baseband signal is transmitted on (N + M) × S subcarriers of an OFDM symbol. This is like dividing the (N + M) signals on an OFDM symbol into (N + M) × S sub-signals and modulating them on (N + M) × S mutually orthogonal subcarriers respectively, thereby realizing OFDM.

[0153] In a possible case, the (N + M) × S subcarriers are consecutive subcarriers. In other words, the numbers of the (N + M) × S subcarriers are consecutive. The above-mentioned (N + M) × S frequency-domain sample points are mapped to and transmitted on consecutive (N + M) × S subcarriers.

[0154] Another possible situation is that the (N + M) × S sub - carriers are in a comb - like shape, and the sub - carrier offset between every two adjacent teeth is equal. In other words, the numbers of the (N + M) × S sub - carriers are discontinuous, but the (N + M) × S sub - carriers are equally spaced. The sub - carrier offset between every two adjacent teeth is equal, that is, the offset between every two adjacent sub - carriers among the (N + M) × S sub - carriers is equal, or the number of offset sub - carriers is the same. For example, the sub - carrier offset is denoted as Z P , Z P is a positive integer.

[0155] It should be noted that if the (N + M) × S frequency - domain samples mapped to the (N + M) × S sub - carriers are converted to the time domain, it is equivalent to performing periodic extension in the time domain with the (N + M) × S time - domain samples as the period, and the (N + M) × S time - domain samples are repeatedly extended (Z P −1) times. Or rather, the number of times the (N + M) × S time - domain samples repeatedly appear in the time domain is Z P , and the number of time - domain samples obtained thereby is Z P ×(N + M) × S. Therefore, from the time - domain perspective, Z P can also be called the repetition times of the (N + M) × S time - domain samples, or rather, the number of periods. By equally spacing the (N + M) × S frequency - domain samples and mapping them to the (N + M) × S sub - carriers, the phase continuity of the (N + M) modulation symbols is ensured, and the generated waveform is a constant - envelope waveform.

[0156] Optionally, the sub - carrier offset Z P is predefined by the protocol, or is configured by the network device, or is determined by the terminal device. Therefore, there may be signaling interaction between the first communication device and the second communication device, and this signaling can be used to carry the first information described below.

[0157] Optionally, the method further includes: the first communication device receives the first information from the second communication device, or rather, the second communication device sends the first information to the first communication device, and this first information is used to indicate the sub - carrier offset Z P .

[0158] For example, the first communication device is a terminal device, the second communication device is a network device or a terminal device, and the second communication device indicates the sub - carrier offset Z P to the first communication device by sending the first information.

[0159] Optionally, the first communication device sends the first information to the second communication device, or rather, the second communication device receives the first information from the first communication device, and this first information is used to indicate the sub - carrier offset Z PFor example, the first communication device is a network device or a terminal device, the second communication device is a terminal device, and the first communication device can indicate the subcarrier offset Z to the second communication device by sending the seventh information. P 。

[0160] Optionally, the first communication device and the second communication device receive first information from a network device, and the first information is used to indicate the subcarrier offset Z. P 。

[0161] For example, both the first communication device and the second communication device are terminal devices, and both the first communication device and the second communication device can receive the first information from the network device.

[0162] Combined with the first aspect or the second aspect, in some possible implementation manners, the sampling rate S is predefined by a protocol, or is configured by a network device, or is determined by a terminal device. Therefore, there may be signaling interaction between the first communication device and the second communication device, and the signaling can be used to carry the second information described below.

[0163] Optionally, the method further includes: the first communication device receives second information from the second communication device, or in other words, the second communication device sends second information to the first communication device, and the second information is used to indicate the sampling rate S.

[0164] For example, the first communication device is a terminal device, the second communication device is a network device or a terminal device, and the second communication device can determine the sampling rate S and indicate the sampling rate S to the first communication device by sending the second information. In other words, the sampling rate S can be configured by the network device or determined by the terminal device. Optionally, the first communication device sends second information to the second communication device, or in other words, the second communication device receives second information from the first communication device, and the second information is used to indicate the sampling rate S.

[0165] Optionally, the method further includes: the first communication device sends second information to the second communication device, or in other words, the second communication device receives second information from the first communication device, and the second information is used to indicate the sampling rate S.

[0166] For example, the first communication device is a network device or a terminal device, the second communication device is a terminal device, and the first communication device can determine the sampling rate S and indicate the sampling rate S to the second communication device by sending the second information. In other words, the sampling rate S can be configured by the network device or determined by the terminal device.

[0167] Optionally, the first communication device and the second communication device receive second information from a network device, and the second information is used to indicate the sampling rate S.

[0168] For example, both the first communication device and the second communication device are terminal devices. The sampling rate S can be configured by a network device, and both the first communication device and the second communication device can receive the second information from the network device.

[0169] The sampling rate S can be used to determine the number of subcarriers included in the frequency-domain resources of the first OFDM baseband signal. Therefore, by means of predefining the sampling rate by protocol, configuring the sampling rate by the network device, or determining the sampling rate by the terminal device and indicating it to the device communicating with it, it can facilitate the first communication device and the second communication device to determine the number of subcarriers included in the frequency-domain resources of the first OFDM baseband signal according to the sampling rate.

[0170] Furthermore, the frequency-domain resources of the first OFDM baseband signal are configured by the network device. Therefore, there may be signaling interaction between the first communication device and the second communication device, and this signaling can be used to carry the eighth information described below.

[0171] Optionally, the method further includes: the first communication device receives the eighth information from the second communication device, or in other words, the second communication device sends the eighth information to the first communication device. The eighth information is used to indicate the position of the frequency band allocated to the first communication device, and the position of the frequency band is used to determine the frequency-domain resources of the first OFDM baseband signal.

[0172] For example, the first communication device is a terminal device, the second communication device is a network device, and the second communication device can configure the position of the frequency band allocated to the first communication device for the first communication device through the eighth information.

[0173] Optionally, the method further includes: the first communication device and the second communication device receive the eighth information from the network device. The eighth information is used to indicate the position of the frequency band allocated to the second communication device, and the position of the frequency band is used to determine the frequency-domain resources of the first OFDM baseband signal.

[0174] For example, both the first communication device and the second communication device are terminal devices, and the network device can indicate the position of the frequency band allocated to the first communication device to the first communication device and the second communication device through the eighth information.

[0175] This frequency band can be, for example, the frequency band allocated by the network device to the first communication device (or in other words, the terminal device) for data transmission. When the eighth information is used to indicate the position of this frequency band, it can specifically indicate the center frequency point and bandwidth of this frequency band, or alternatively, it can also indicate at least two of the start position, end position, and bandwidth of this frequency band. This application does not make any limitations in this regard.

[0176] Based on the position of the frequency band allocated to the terminal device and in combination with the above-mentioned subcarrier offset, the absolute positions of the (N + M) × S subcarriers can be determined, and further the subcarriers where each modulation symbol in the second symbol sequence is located can be determined.

[0177] Combining the first aspect to the third aspect, in some possible implementation manners, the length of the CP of the first OFDM baseband signal (i.e., the first CP) is predefined by the protocol, or is configured by the network device, or is configured by the terminal device. Therefore, there may be signaling interaction between the first communication device and the second communication device, and this signaling can be used to carry the third information described below.

[0178] The length of the first CP can be represented by the number of modulation symbols corresponding to this first CP. For example, in the first aspect, the modulation symbols corresponding to the first CP are the K 1 modulation symbols at the end of the second symbol sequence; in the second aspect, the first CP corresponds to the first CP sequence, and the first CP sequence consists of the K 1 modulation symbols at the end of the fourth symbol sequence. Therefore, K 1 is the length of the first CP. In addition, in the second aspect, the length of the first CP is equal to the length of the first CP sequence, both being K 1 .

[0179] A possible situation is that the first communication device is a terminal device, and the terminal device can use all of the allocated frequency-domain resources to transmit the first OFDM baseband signal. At this time, the above-mentioned (N + M) × S subcarriers can occupy the frequency band allocated to the terminal device, including continuous or comb-shaped ones. For example, if the terminal device is allocated a 10-megahertz (MHz) frequency band, the (N + M) × S subcarriers can continuously occupy this 10 MHz, or can also be distributed in a comb shape on this 10 MHz frequency band.

[0180] In this case, the length of the first CP can correspond to the bandwidth of the frequency band allocated to the terminal device. The terminal device can determine the length of the first CP according to the system bandwidth and its corresponding CP length, as well as the bandwidth of the allocated frequency band. That is to say, the length of the first CP is determined by the terminal device. Among them, the bandwidth of the frequency band allocated to the terminal device can be configured or predefined by the network device, and one or more of the system bandwidth and its corresponding CP length can also be configured or predefined by the network device.

[0181] Or, the length of the first CP can be configured by the network device. For example, the network device directly indicates the bandwidth of the frequency band allocated to the first communication device and the corresponding CP length to the first communication device.

[0182] Another possible scenario is that the first communication device is a terminal device, and the terminal device can use a part of the allocated frequency-domain resources (denoted as the target frequency band for easy distinction and description) to transmit the first OFDM baseband signal. In this case, the above (N + M) × S subcarriers can be continuous. For example, if the terminal device is allocated a 10 MHz frequency band, the (N + M) × S subcarriers can continuously occupy 5 MHz of it.

[0183] In this case, the length of the first CP can correspond to the bandwidth of the frequency band actually used by the terminal device to transmit the first OFDM baseband signal. The terminal device can determine the length of the first CP based on the system bandwidth and its corresponding CP length, as well as the bandwidth of the target frequency band actually used by the terminal device. Among them, one or more of the system bandwidth and its corresponding CP length can be configured or predefined by the network device. The bandwidth of the target frequency band actually used by the terminal device can be determined by the terminal device.

[0184] Yet another possible scenario is that the first communication device is a network device, and the network device can determine the length of the first CP based on the system bandwidth and its corresponding CP length, as well as the bandwidth of the target frequency band actually used. Among them, one or more of the system bandwidth and its corresponding CP length can be determined by the network device itself.

[0185] It should be understood that the bandwidth of the target frequency band can be less than or equal to the bandwidth allocated by the network device.

[0186] Optionally, the method further includes: the first communication device receives third information from the second communication device, or in other words, the second communication device sends third information to the first communication device, and the third information is used to indicate the length of the first CP.

[0187] For example, if the first communication device is a terminal device and the second communication device is a network device, the length of the first CP can be configured by the network device. Therefore, the second communication device can configure the length of the CP for the first communication device through the third information.

[0188] When the third information is used to indicate the length of the first CP, for example, it may include the length information of the first CP, or include: the bandwidth of the frequency band allocated to the first communication device.

[0189] The length information of the first CP can be the number of modulation symbols included in the first CP, or information that can be used to identify the number of modulation symbols included in the first CP. That is, the third information is used to indicate K 1 .

[0190] The ratio of the system bandwidth to the bandwidth of the frequency band allocated to the terminal device is equal to the ratio of the CP length corresponding to the system bandwidth to the CP length corresponding to the bandwidth of the frequency band allocated to the terminal device. Or rather, the ratio of the bandwidth of the frequency band allocated to the terminal device to its corresponding CP length is equal to the ratio of the system bandwidth to its corresponding CP length. Therefore, according to the system bandwidth, the CP length corresponding to the system bandwidth, and the bandwidth of the frequency band allocated to the terminal device, the length of the first CP can also be determined.

[0191] For another example, the first communication device is a terminal device and the second communication device is a network device. The length of the first CP can be determined by the terminal device. Therefore, the terminal device can indicate the length of the first CP to the network device through the third information.

[0192] When the third information is used to indicate the length of the first CP, for example, it may include the length information of the first CP, or include: the bandwidth of the target frequency band actually used by the first communication device.

[0193] The length information of the first CP can be the number of modulation symbols included in the first CP, or information that can be used to identify the number of modulation symbols included in the first CP.

[0194] The ratio of the bandwidth of the target frequency band to the system bandwidth is equal to the ratio of the length of the first CP to the CP length corresponding to the system bandwidth. Or rather, the ratio of the target frequency band to its corresponding first CP length is equal to the ratio of the system bandwidth to its corresponding CP length. Therefore, according to the system bandwidth, the CP length corresponding to the system bandwidth, and the bandwidth of the target frequency band, the length of the first CP can also be determined.

[0195] Optionally, the method further includes: the first communication device sends the third information to the second communication device, or rather, the second communication device receives the third information from the first communication device, and the third information is used to indicate the length of the first CP.

[0196] For example, the first communication device is a network device and the second communication device is a terminal device. The length of the first CP can be configured by the network device. Therefore, the first communication device can configure the length of the first CP for the second communication device through the third information.

[0197] For another example, the first communication device is a terminal device and the second communication device is a network device. The length of the first CP can be determined by the terminal device. Therefore, the terminal device can indicate the length of the first CP to the network device through the third information.

[0198] Regarding the content included in the third information, reference can be made to the examples above and will not be elaborated here.

[0199] Optionally, the method further includes: the first communication device and the second communication device receive third information from a network device, where the third information is used to indicate the length of the first CP.

[0200] For example, both the first communication device and the second communication device are terminal devices, and the length of the first CP can be configured by the network device. Therefore, both the first communication device and the second communication device can receive the third information from the network device.

[0201] For the content included in the third information, reference can be made to the above examples and will not be elaborated here.

[0202] Combined with the first aspect to the third aspect, the modulation parameters are predefined by the protocol, or determined by the first communication device, or determined by the second communication device. Therefore, there may be signaling interaction between the first communication device and the second communication device, and the signaling can be used to carry the fourth information described below, where the fourth information can be used to indicate one or more of the modulation parameters.

[0203] In one example, the modulation is CPM, and the parameters of CPM include: the frequency pulse shaping function of CPM, the phase pulse shaping function of CPM, the modulation index of CPM, or the initial phase of CPM.

[0204] Among the frequency pulse shaping function of CPM, the phase pulse shaping function of CPM, the modulation index of CPM, and the initial phase of CPM, all can be determined by the first communication device or the second communication device, or part can be determined by the first communication device and the other part can be determined by the second communication device, or part can be determined by the first communication device and / or the second communication device and the other part is predefined by the protocol, or all can be predefined by the protocol. This application does not make any limitations in this regard.

[0205] Optionally, the method further includes: the first communication device receives fourth information from the second communication device, or in other words, the second communication device sends the fourth information to the first communication device, where the fourth information is used to indicate one or more of the following: the frequency pulse shaping function of CPM, the phase pulse shaping function of CPM, the modulation index of CPM, or the initial phase of CPM.

[0206] For example, the first communication device is a terminal device and the second communication device is a network device, and the above one or more parameters can be configured by the network device. Therefore, the first communication device can receive the fourth information from the second communication device.

[0207] Optionally, the method further includes: a first communication device sending fourth information to a second communication device, or alternatively, the second communication device receiving the fourth information from the first communication device, where the fourth information is used to indicate one or more of the following: the frequency pulse shaping function of CPM, the phase pulse shaping function of CPM, the modulation index of CPM, or the initial phase of CPM.

[0208] For example, the first communication device is a network device, the second communication device is a terminal device, and the modulation parameters can be configured by the network device. Therefore, the first communication device can send the fourth information to the second communication device.

[0209] Another example is that the first communication device is a terminal device, and the second communication device is a network device or a terminal device. One or more of the above parameters can be determined by the terminal device. Therefore, the first communication device can send the fourth information to the second communication device.

[0210] Another example is that the modulation is LFM, and the parameters of LFM include: the chirp rate of LFM.

[0211] Optionally, the method further includes: the first communication device receiving fourth information from the second communication device, or alternatively, the second communication device sending the fourth information to the first communication device, where the fourth information is used to indicate the chirp rate of LFM.

[0212] Optionally, the method further includes: the first communication device sending fourth information to the second communication device, or alternatively, the second communication device receiving the fourth information from the first communication device, where the fourth information is used to indicate the chirp rate of LFM.

[0213] For examples of the first communication device receiving the fourth information from the second communication device and the first communication device sending the fourth information to the second communication device, reference can be made to the above, and details will not be repeated.

[0214] In a fourth aspect, a baseband chip is provided. The baseband chip can be applied to the first communication device in the first aspect and can be used to implement the functions of the first communication device implemented at the baseband in the first aspect. Since the content in the first aspect has been described in detail above, it will not be elaborated below.

[0215] Exemplarily, the baseband chip includes: a processing circuit configured to obtain a first symbol sequence, where the first symbol sequence includes N symbols to be transmitted, and N is a positive integer; the processing circuit is further configured to: based on the first symbol sequence, obtain a second symbol sequence, where the symbols in the second symbol sequence are obtained by mapping (N + M) modulated symbols to resource elements (REs), the (N + M) modulated symbols are obtained by modulating a third symbol sequence, the third symbol sequence includes the N symbols to be transmitted in the first symbol sequence and M extended symbols, the M extended symbols make the phases of the (N + M) modulated symbols obtained by the modulation continuous, and the phase difference between the phase at the starting position and the phase at the ending position is an integer multiple of 2π, and M is an integer greater than or equal to zero; the processing circuit is further configured to: generate a first OFDM baseband signal based on the second symbol sequence, and the time-domain resource of the first OFDM baseband signal is one OFDM symbol.

[0216] Optionally, the baseband chip further includes an interface circuit configured to output the first OFDM baseband signal.

[0217] In a fifth aspect, a baseband chip is provided. The baseband chip can be applied to the first communication device in the second aspect and can be used to implement the functions of the first communication device in the second aspect at the baseband. Since the content in the second aspect has been described in detail above, it will not be elaborated below.

[0218] Exemplarily, the baseband chip includes: a processing circuit configured to obtain a first symbol sequence, where the first symbol sequence includes N symbols to be transmitted, and N is a positive integer; the processing circuit is further configured to: based on the first symbol sequence, generate a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence, the first CP sequence is the K 1 symbols at the end of the fourth symbol sequence, the symbols in the fourth symbol sequence are (N + M) modulated symbols obtained by modulating a third symbol sequence, the third symbol sequence includes the N symbols to be transmitted in the first symbol sequence and M extended symbols, the M extended symbols make the phases of the fourth symbol sequence obtained by the modulation continuous, and the phase difference between the phase at the starting position and the phase at the ending position is an integer multiple of 2π, and M is an integer greater than or equal to zero; the processing circuit is further configured to: generate a first OFDM baseband signal based on the fourth symbol sequence and the first CP sequence, and the time-domain resource of the first OFDM baseband signal is one OFDM symbol.

[0219] Optionally, the baseband chip further includes an interface circuit configured to output the first OFDM baseband signal.

[0220] In a sixth aspect, a chip system is provided, including: a radio frequency chip and the baseband chip described in the fourth aspect or the fifth aspect. Among them, the baseband chip is used to generate a first OFDM baseband signal; the radio frequency chip is used to obtain a bandpass signal based on the first OFDM baseband signal from the baseband chip; and is used to perform power amplification on the bandpass signal to obtain a power-amplified bandpass signal.

[0221] Furthermore, a transmitter is also provided, including the aforementioned chip system.

[0222] Optionally, the transmitter further includes an antenna for transmitting the power-amplified bandpass signal.

[0223] In combination with the sixth aspect, in some possible implementation manners of the sixth aspect, the radio frequency chip includes: an up-conversion module and a power amplifier. The up-conversion module is used to obtain and output a bandpass signal based on the first OFDM baseband signal from the baseband chip; the power amplifier is used to perform power amplification on the bandpass signal to obtain a power-amplified bandpass signal.

[0224] In combination with the sixth aspect, in some possible implementation manners of the sixth aspect, the bandpass signal is a frequency-modulated signal, and the up-conversion module is specifically used to directly frequency-modulate a carrier based on the first OFDM baseband signal to obtain the frequency-modulated signal.

[0225] Directly frequency-modulating the carrier based on the first OFDM baseband signal means controlling the up-conversion module by the first OFDM baseband signal to generate a frequency-modulated waveform that changes with time, so that the mixing operation through a mixer can be omitted. Comparatively speaking, the structure of the transmitter and the up-conversion operation can be simplified, power consumption can be saved, and thus the cost and transmission power consumption are lower.

[0226] As an example rather than a limitation, the up-conversion module includes a phase-locked loop (PLL), a voltage controlled oscillator (VCO), or a digitally controlled oscillator (DCO). It should be understood that the present application does not limit the specific devices included in the up-conversion module. As long as a sinusoidal wave with adjustable frequency can be generated, the above PLL, VCO, or DCO can also be replaced to achieve direct frequency modulation.

[0227] It should also be understood that direct frequency modulation is only one possible implementation manner and should not limit the protection scope of the present application. The up-conversion module can also be used to perform a mixing operation on the first OFDM baseband signal to output a bandpass signal. In this case, the up-conversion module can include: one of PLL, VCO, or DCO, and a mixer.

[0228] In combination with the sixth aspect, in some possible implementation manners of the sixth aspect, the power amplifier is a non-linear power amplifier, and the non-linear power amplifier can be used for non-linearly amplifying a band-pass signal.

[0229] Based on the above technical solution, the baseband chip can output a signal with a constant envelope waveform. Therefore, in the radio frequency processing stage, direct conversion can be used to replace the mixing operation, and non-linear power amplification can be used to replace linear power amplification. In this way, not only can the signal be transmitted in a manner with lower transmission power consumption, saving a large amount of power consumption and increasing the standby life, but also the structure of the transmitter can be simplified, such as removing the mixer and replacing the linear power amplifier with a non-linear power amplifier, etc., so the cost is lower.

[0230] It should be understood that non-linear amplification is only one possible implementation manner and should not constitute any limitation to the protection scope of the present application. The power amplifier can also be a linear power amplifier, which is used for linearly amplifying a band-pass signal. The present application does not make any limitation in this regard.

[0231] The seventh aspect provides a communication device, which can be used to implement the functions of the first communication device in the first aspect or the second aspect. Exemplarily, the communication device may include a baseband chip as described in the fourth aspect or the fifth aspect, or include a transmitter as described in the sixth aspect.

[0232] Optionally, the communication device is a terminal device.

[0233] The eighth aspect provides a baseband chip, which can be applied to the second communication device in the third aspect and can be used to implement the functions of the second communication device in the third aspect achieved at the baseband. Since the content in the third aspect has been described in detail above, it will not be elaborated below.

[0234] Exemplarily, the baseband chip includes: an interface circuit and a processing circuit. The interface circuit can be used to obtain a first OFDM baseband signal; the processing circuit can be used to: based on the first OFDM baseband signal, obtain a fourth symbol sequence, the fourth symbol sequence includes L modulation symbols, L is a positive integer; demodulate the fourth symbol sequence to obtain a third symbol sequence, the third symbol sequence includes N first symbols and M extended symbols, L = M + N, N is a positive integer less than or equal to L, and M is an integer greater than or equal to zero; determine the positions of the M extended symbols in the third symbol sequence and the value of M; and obtain N first symbols from the third symbol sequence.

[0235] In a ninth aspect, a chip system is provided, including: a radio frequency chip and the baseband chip described in the eighth aspect. Among them, the radio frequency chip is used to output a first OFDM baseband signal based on a bandpass signal; the baseband chip is used to obtain N first symbols based on the first OFDM baseband signal.

[0236] Further, this aspect also provides a receiver, including the aforementioned chip system.

[0237] Optionally, the receiver further includes an antenna for receiving a bandpass signal.

[0238] In a tenth aspect, a communication device is provided, which can be used to implement the functions of the second communication device in the third aspect. Exemplarily, the communication device may include the baseband chip described in the eighth aspect, or include the receiver described in the ninth aspect.

[0239] Optionally, the communication device is a network device.

[0240] In an eleventh aspect, a communication device is provided, which can implement the communication method described in any one of the first to third aspects above. The device includes corresponding units or modules for executing the above method. The units or modules included in the device can be implemented in software and / or hardware. The communication device can be the baseband chip in the fourth or fifth aspect, or the chip system or transmitter in the sixth aspect, or the communication device in the seventh aspect, or the baseband chip in the eighth aspect, or the chip system or receiver in the ninth aspect, or the communication device in the tenth aspect.

[0241] In a twelfth aspect, a computer-readable storage medium is provided, including a computer program, and when it runs on a computer, the method in any one of the first to third aspects above is executed.

[0242] In a thirteenth aspect, a computer program product is provided, and the computer program product includes: a computer program (which can also be called code or instruction), and when the computer program runs, the method in any one of the first to third aspects is executed.

[0243] In a fourteenth aspect, an embodiment provides a communication system, including the aforementioned first communication device and second communication device.

[0244] Combined with the above aspects, in some possible implementation manners, the first communication device is a terminal device, and the second communication device is a network device; or, the first communication device is a terminal device, and the second communication device is a terminal device; or, the first communication device is a network device, and the second communication device is a terminal device.

[0245] It should be understood that the technical solutions of the fourth to fourteenth aspects of the present application correspond to those of the first to third aspects of the present application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation manners are similar, and will not be described in detail hereinafter. Description of the Drawings

[0246] Figure 1 is a schematic diagram of a communication system applicable to the communication method provided in the embodiment of the present application;

[0247] Figure 2 is a schematic diagram of several different communication scenarios applicable to the communication method provided in the embodiment of the present application;

[0248] Figure 3 is a schematic diagram of the structure of a transmitter currently applied to a terminal device;

[0249] Figure 4 is a schematic diagram of the structure of a transmitter applicable to the communication method provided in the embodiment of the present application;

[0250] Figure 5 is a schematic diagram of the signal processing process provided in the embodiment of the present application;

[0251] Figure 6 is a schematic flowchart of the communication method provided in an embodiment of the present application;

[0252] Figure 7 is a schematic diagram of the third symbol sequence provided in an embodiment of the present application;

[0253] Figure 8 is a schematic diagram of generating a fourth symbol sequence based on the third symbol sequence provided in an embodiment of the present application;

[0254] Figure 9 is another schematic diagram of generating a fourth symbol sequence based on the third symbol sequence provided in an embodiment of the present application;

[0255] Figure 10 is a schematic diagram of (N + M) × S subcarriers provided in an embodiment of the present application;

[0256] Figure 11 is a schematic diagram of mapping the fourth symbol sequence to the REs to obtain the second symbol sequence provided in an embodiment of the present application;

[0257] Figure 12A is a schematic diagram of the processing process of a terminal device from obtaining the first symbol sequence to transmitting a bandpass signal provided in an embodiment of the present application;

[0258] Figure 12B is another schematic diagram of the processing process of a terminal device from obtaining the first symbol sequence to transmitting a bandpass signal provided in an embodiment of the present application;

[0259] Figure 13A It is another schematic diagram of the processing process of the terminal device from obtaining the first symbol sequence to transmitting the band-pass signal provided by an embodiment of the present application;

[0260] Figure 13B It is still another schematic diagram of the processing process of the terminal device from obtaining the first symbol sequence to transmitting the band-pass signal provided by an embodiment of the present application;

[0261] Figure 14 It is a schematic diagram of the processing process of the network device from receiving the band-pass signal to obtaining the first symbol sequence provided by an embodiment of the present application;

[0262] Figure 15 It is a schematic flowchart of a communication method provided by another embodiment of the present application;

[0263] Figure 16 It is a schematic diagram of generating a fourth symbol sequence and a first CP sequence based on a third symbol sequence provided by another embodiment of the present application;

[0264] Figure 17 It is a schematic diagram of an eighth symbol sequence provided by another embodiment of the present application;

[0265] Figure 18 It is a schematic diagram of the processing process of the terminal device from obtaining the first symbol sequence to transmitting the band-pass signal provided by another embodiment of the present application;

[0266] Figure 19 It is another schematic diagram of the processing process of the terminal device from obtaining the first symbol sequence to transmitting the band-pass signal provided by another embodiment of the present application;

[0267] Figure 20 It is a simulation diagram provided by an embodiment of the present application;

[0268] Figure 21 It is a schematic diagram of the time-domain resources of the reference signal and the data signal provided by an embodiment of the present application;

[0269] Figure 22 It is a schematic diagram of the frequency-domain resources of the reference signal and the data signal provided by an embodiment of the present application;

[0270] Figure 23 It is a schematic diagram of the symbol sequence on the first OFDM symbol and the second OFDM symbol provided by an embodiment of the present application;

[0271] Figure 24 It is a schematic diagram of phase compensation provided by an embodiment of the present application;

[0272] Figure 25 It is another schematic diagram of phase compensation provided by an embodiment of the present application;

[0273] Figure 26 It is a schematic diagram of the processing process of multiple symbol sequences provided by an embodiment of the present application;

[0274] Figure 27 It is a schematic flowchart of a communication method provided by another embodiment of the present application;

[0275] Figure 28 It is a schematic block diagram of a communication device provided by an embodiment of the present application;

[0276] Figure 29 It is a schematic block diagram of a baseband chip provided by an embodiment of the present application;

[0277] Figure 30 It is a schematic block diagram of a communication device provided by an embodiment of the present application. Detailed implementation manners

[0278] Next, the technical solutions in the present application will be described in conjunction with the accompanying drawings.

[0279] For the convenience of understanding the embodiments of the present application, the following points are first explained:

[0280] First, multiple letters are used in the present application to represent different parameters. For the convenience of understanding, a brief description of the used letters is given here.

[0281] N: The number of symbols to be transmitted in the first symbol sequence, N is a positive integer;

[0282] M: The number of extended symbols in the third symbol sequence, M is an integer greater than or equal to zero;

[0283] K 1 : The length of the first CP, K 1 is a positive integer;

[0284] K 2 : The length of the second CP, K 2 is a positive integer;

[0285] S: Sampling rate, S is a positive integer;

[0286] Z p : The subcarrier offset between every two adjacent subcarriers in the frequency domain resource of the second symbol sequence, Z p is a positive integer;

[0287] a: The first symbol sequence, which may include N symbols to be transmitted: a 1 , a 2 , a 3 , ……, a N ;

[0288] ​​​​​​​​​​The third symbol sequence may include N symbols to be transmitted and M extended symbols.

[0289] Second, in this application, a symbol sequence is composed of one or more symbols in a certain order, and can also be referred to as a symbol block. The symbol sequence can be used to define symbols and the order between symbols. The symbol sequence in this article can be a sequence composed of one or more symbols before modulation (such as symbols to be transmitted, or symbols to be transmitted and extended symbols) in a certain order, or a sequence composed of one or more modulated symbols in a certain order after modulation.

[0290] Third, in this application, two modulation operations are performed at the signal transmitting end (such as the first communication device described above), namely modulation and CPM or LFM. Among them, modulation is one-dimensional modulation, which is used to modulate bits into modulated symbols (such as the N symbols to be transmitted in the first symbol sequence in this application), and CPM or LFM is used to modulate the modulated symbols obtained by modulation onto the phase or frequency of the carrier.

[0291] Correspondingly, at the signal receiving end (such as the second communication device described above), two demodulation operations can also be performed, namely demodulation corresponding to modulation and demodulation corresponding to CPM or LFM. Among them, the demodulation corresponding to CPM or LFM can be abbreviated as CPM demodulation or LFM demodulation, which is used to demodulate the modulated symbol sequence from the carrier, and the demodulation corresponding to modulation is used to demodulate the modulated symbol sequence demodulated by CPM demodulation or LFM demodulation to obtain the bit sequence.

[0292] In this application, for the convenience of distinction and understanding, the symbols obtained through CPM or LFM are collectively referred to as modulated symbols, the symbols before CPM or LFM are denoted as symbols to be transmitted or extended symbols, or collectively referred to as symbols, and the symbols obtained through CPM demodulation or LFM demodulation are denoted as first symbols or extended symbols, or collectively referred to as symbols.

[0293] Fourth, in this application, the offset can be used to represent the offset degree between two objects, or the distance between two objects. For example, the subcarrier offset can be obtained by subtracting the numbers of two subcarriers.

[0294] Fifth, in this application, indication includes direct indication (also called explicit indication) and implicit indication (also called indirect indication). Among them, direct indication of information A means including this information A; implicit indication of information A means indicating information A through the correspondence between information A and information B and direct indication of information B. Among them, the correspondence between information A and information B can be predefined, pre-stored, pre-burned, or pre-configured.

[0295] Sixth, in this application, information C is used to determine information D, which includes both the case where information D is determined solely based on information C and the case where information D is determined based on information C and other information. In addition, when information C is used to determine information D, there may also be an indirect determination situation. For example, information D is determined based on information E, and information E is determined based on information C.

[0296] Seventh, for ease of understanding, the signal processing process is described in this application through multiple drawings. These drawings are only examples and should not impose any limitations on this application. For example, the sequence of steps shown in each drawing can be simply changed according to their functions and internal logic; for another example, all the steps in each drawing can be executed, or only a part of them can be executed, as long as the same functions as those in the embodiments of this application can be achieved. Eighth, in this application, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship between associated objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship, but it does not exclude the case where the associated objects before and after are in an "and" relationship. The specific meaning represented can be understood in combination with the context. "At least one (item)" or its similar expression refers to any combination of these items, including any combination of single item (s) or plural items (s). For example, at least one (item) of a, b, or c can represent: a, b, c; a and b; a and c; b and c; or a, b, and c. Where a, b, and c can be single or multiple.

[0297] Ninth, in this application, the use of prefix words such as "first" and "second" is only for facilitating the differential description of different things belonging to the same name category, and does not restrict the order, size, or quantity of things. For example, "the first communication device" and "the second communication device" are just different devices, and do not limit the number or the high-low relationship of priorities of the devices; for another example, "the first information" and "the second information" are just different information, and there is no time sequence relationship, size relationship, or high-low relationship of priorities between the two.

[0298] Tenth, in this application, "transmission" and "reception" indicate the direction of signal transmission. For example, "transmitting information to a network device" can be understood as the destination of the information being the network device, which can include direct transmission via the air interface or indirect transmission via other units or modules through the air interface. "Receiving information from a network device" can be understood as the source of the information being the network device, which can include directly receiving from the network device via the air interface or indirectly receiving from the network device via other units or modules through the air interface. "Transmission" can also be understood as the "output" of the chip interface, and "reception" can also be understood as the "input" of the chip interface.

[0299] In other words, transmission and reception can occur between devices, for example, between a network device and a terminal device; or they can occur within a device, for example, transmission or reception between components, modules, chips, software modules, or hardware modules within a device via a bus, trace, or interface.

[0300] Eleventh, in the embodiments of this application, "when", "if", and "in case" all refer to the device performing corresponding processing under certain objective circumstances, not limiting time, and not requiring the device to have a judgment action when implemented, nor implying other limitations.

[0301] Twelfth, in this application, words such as "example", "exemplarily", "for example", or "such as" are used to give examples, illustrations, or explanations. Any embodiment or design described as "example", "exemplarily", "for example", or "such as" in this application should not be construed as being more preferred or having more advantages than other embodiments or designs. Rather, using words such as "example", "exemplarily", "for example", or "such as" is intended to present relevant concepts in a specific manner.

[0302] Thirteenth, for ease of understanding, the following text uses multiple figures to illustrate the processing procedures of each device. For example, Figures 12A to 14 、 Figure 16 、 Figure 18 、 Figure 19 、 Figures 24 to 26And so on. Each operation in the processing procedures shown in the figures can be implemented by a corresponding module respectively. For example, modulation can be implemented by a modulation module, sampling can be implemented by a sampling module, or modulation and sampling can be implemented by a modulation module. For another example, Fourier transform and frequency-domain mapping can be implemented by an RE mapping module; or time-domain periodic extension can be implemented by an RE mapping module. For still another example, OFDM baseband signal generation can be implemented by an OFDM baseband generation module. For yet another example, demodulation can be implemented by a demodulation module. And so on. Such examples are not enumerated one by one. The specific implementation manners of each module to implement its corresponding operation have been described correspondingly in steps 601 to 606 above. For more detailed descriptions, reference can be made to the above text, and no further elaboration will be given here. In addition, the division of each module is only a division of logical functions, and there can be other division manners in actual implementation. For example, some modules can be combined into one module, or some modules can be split into more modules, and so on. The present application does not make any limitation in this regard.

[0303] Fourteenth, the first to ninth information in the present application is only defined for facilitating the distinction of their respective functions, and should not impose any limitation on the quantity of the information, the number of times of sending the information, and the signaling carrying these information. In some implementation manners, some information (such as at least two of the first to ninth information) can be carried in the same signaling and be implemented through one sending step (for the sender) or one receiving step (for the receiver); in some other implementation manners, some information (such as a certain one of the first to ninth information) can also be carried by the information elements in multiple signallings and be implemented through multiple sending steps (for the sender) or multiple receiving steps (for the receiver).

[0304] Fifteenthly, in the embodiments of the present application, the methods provided by the embodiments of the present application are described by taking a cellular system related to the 3rd generation partnership project (3GPP) as an example, but this should not impose any limitation on the present application. Based on the same concept, the methods provided by the present application can also be applied to other communication networks such as ZigBee, Long Range Radio (LoRa), Bluetooth (BT), and Wireless Fidelity (Wi-Fi). For example, the method provided by the present application can be applied to a ZigBee network to replace the Chirp Spread Spectrum (CSS) modulation in Section 14 of the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4, the Gauss Frequency Shift Keying (GFSK) in Section 16, the Minimum Shift Keying (MSK) in Section 17, or the Orthogonal Frequency Division Multiplexing (OFDM) in Section 25 of IEEE 802.15.4 with the OFDM waveform generated by this solution; for another example, the method provided by the present application can be applied to Bluetooth communication to replace the GFSK in Section 3 of the Bluetooth Core Specification; for yet another example, the method provided by the present application can be applied to LoRa communication to replace the CSS; for still another example, the method provided by the present application can be applied to a Wi-Fi system to replace the OFDM waveform defined in IEEE 802.11 with the OFDM waveform generated by this solution.

[0305] It can be understood that by applying the solution provided by the present application to different communication networks, the interference of the multipath channel can be reduced by using the cyclic prefix (CP) during the broadband signal transmission.

[0306] To better understand the embodiments of the present application, the terms related to the present application are briefly described below.

[0307] I. Constant envelope waveform: It refers to a waveform whose envelope amplitude remains constant. This requires that during the modulation process, not only the amplitude remains unchanged, but also the phase is continuous and does not jump. The maximum power value and the average power value of the constant envelope waveform are equal everywhere, and the peak-to-average power ratio (PAPR) of the envelope is 1. If the PAPR is represented by logarithm, taking the logarithm of 1, the PAPR can be obtained as 0 dB.

[0308] II. Phase modulation (PM) is a modulation method that realizes information transmission by changing the phase of the carrier at the frequency of the modulation signal. It superimposes the information to be transmitted onto the carrier signal by changing the phase of the carrier. In other words, the amplitude of the carrier signal is not used to carry information.

[0309] III. Frequency modulation (FM) is a modulation method that represents the information to be transmitted by the instantaneous frequency of the carrier. It superimposes the information to be transmitted onto the carrier signal by changing the frequency of the carrier. In other words, the amplitude of the carrier signal is not used to carry information.

[0310] IV. Direct frequency modulation: The oscillation frequency of the oscillator is directly controlled by the modulation signal, so that it can truly reflect the change law of the modulation signal without distortion.

[0311] V. Linear PA and non-linear PA: Linear PA is used for linearly amplifying signals. The increase in the output signal strength has a 1:1 relationship with the increase in the input signal strength. The signal after linear amplification has less distortion, but the power consumption caused by linear amplification is relatively large.

[0312] Non-linear PA is used for non-linearly amplifying signals. The input-output function of the signal does not maintain a 1:1 equal-amplitude growth relationship, but shows non-limited amplification. The non-linear method will cause amplitude distortion of the signal, but the power consumption of non-linear amplification is relatively small.

[0313] VI. Baseband signal: The original signal sent from the transmitting end without modulation (such as spectrum shifting and transformation). Its characteristic is that the frequency is relatively low and near zero frequency.

[0314] The OFDM baseband signal in this application is an OFDM baseband signal based on CP. For the convenience of understanding and explanation, the OFDM baseband signal is divided into two parts in this article: the signal body and CP. Among them, CP is obtained by copying some symbols at the end of the signal body to before the signal body. That is to say, CP constitutes the head of the OFDM baseband signal.

[0315] VII. Bandpass signal: Since the baseband signal has a low frequency and large transmission loss, it is necessary to modulate the signal to a high frequency. The bandpass signal is the signal after the baseband signal is modulated by the carrier. By shifting the frequency range of the signal to a higher frequency band, the signal can pass through the channel within a certain frequency range, so as to be transmitted in the channel.

[0316] VIII. OFDM Technology: A frequency division multiplexing technology that divides a channel into several orthogonal sub-channels, converts a high-speed data signal into parallel low-speed sub-data streams, and modulates them for transmission on each sub-channel. By using OFDM technology, multi-carrier transmission can be achieved, making full use of the channel bandwidth.

[0317] VII. Target Frequency Band: In the embodiments of the present application, for the convenience of distinction and description, the frequency band corresponding to the frequency domain resources actually used to transmit the first OFDM baseband signal is denoted as the target frequency band. The bandwidth of the target frequency band can be less than or equal to the bandwidth of the frequency band allocated by the network device. Since the first OFDM baseband signal is generated based on the second symbol sequence, and the second symbol sequence is in turn generated based on the first symbol sequence, the first symbol sequence includes N symbols to be transmitted, and the first OFDM baseband signal can be up-converted to obtain a band-pass signal. Therefore, the frequency domain resources used to transmit the first OFDM baseband signal can also be referred to as the frequency domain resources used to transmit the second symbol sequence, or the frequency domain resources used to transmit the first symbol sequence, or the frequency domain resources used to transmit N symbols to be transmitted, or the frequency domain resources used to transmit the band-pass signal.

[0318] The technical solutions provided in this application can be applied to various communication systems, such as: the 5th generation (5G) or new radio (NR) system, the long term evolution (LTE) system, the LTE frequency division duplex (FDD) system, the LTE time division duplex (TDD) system, the wireless local area network (WLAN) system, the satellite communication system, future communication systems such as the 6th generation (6G) mobile communication system, or a fusion system of multiple systems, etc. The technical solutions provided in this application can also be applied to device-to-device (D2D) communication, vehicle-to-everything (V2X) communication, machine-to-machine (M2M) communication, machine type communication (MTC), and the Internet of Things (IoT) communication system or other communication systems.

[0319] A device in a communication system can send signals to another device or receive signals from another device. The signals can include information, signaling, data, etc. Herein, the device can also be replaced with an entity, a network entity, a communication device, a communication module, a node, a communication node, etc. In this disclosure, the description is made by taking the device as an example. For example, a communication system can include at least one terminal device and at least one network device. The network device can send downlink signals to the terminal device, and / or the terminal device can send uplink signals to the network device. It can be understood that the terminal device in this disclosure can be replaced with a first communication device, and the network device can be replaced with a second communication device, and both execute the corresponding communication methods in this disclosure.

[0320] The radio access network (RAN) device in this application is a device with wireless transceiver functions. The radio access network device can provide wireless communication function services and can connect the terminal device to the wireless network. The radio access network can also be referred to as an access network device or a network device. The network device in the embodiments of this application can refer to a radio access network (RAN) node (or device) that is applied to a cellular network (or a mobile network) to connect the terminal device to the wireless network, and can also be a zigbee base station, a master Bluetooth (BT master), a master low energy (bluetooth low energy, BLE) Bluetooth (BLE master), a Lora base station, or a Wi-Fi access point.

[0321] For example, the network device can be a base station. The base station can generally cover various names as follows, or be replaced with the following names, such as: Node B, evolved Node B (eNB), next-generation Node B (gNB), relay station, access point, transmitting and receiving point (TRP), transmitting point (TP), master station, slave station, multi-mode radio (MSR) node, home base station, network controller, access node, radio node, access point (AP), transmission node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), radio unit (RU), positioning node, etc. The base station can be a macro base station, micro base station, relay node, donor node or the like, or a combination thereof. The base station can also refer to a communication module, modem or chip used in the foregoing device or apparatus. The base station can also be a mobile switching center and devices that perform the functions of a base station in D2D, V2X, M2M communications, network-side devices in 6G networks, devices that perform the functions of a base station in future communication systems, etc. The base station can support networks with the same or different access technologies. Optionally, the RAN node can also be a server, wearable device, vehicle or in-vehicle device, etc. For example, the access network device in vehicle-to-everything (V2X) technology can be a road side unit (RSU). The embodiments of the present application do not limit the specific technologies and specific device forms adopted by the network device. In some deployments, the network device mentioned in the embodiments of the present application can be a device including a CU, or a DU, or a device including a CU and a DU, or a device including a control-plane CU node (central unit-control plane (CU-CP)) and a user-plane CU node (central unit-user plane (CU-UP)) and a DU node. For example, the network device can include a gNB-CU-CP, a gNB-CU-UP and a gNB-DU.

[0322] In some deployments, multiple RAN nodes cooperate to assist a terminal in achieving wireless access, and different RAN nodes respectively implement some functions of a base station. For example, the RAN node can be a CU, DU, CU-CP, CU-UP, or RU, etc. The CU and DU can be separately set, or can also be included in the same network element, such as a BBU. The RU can be included in a radio frequency device or a radio frequency unit, such as included in an RRU, AAU, or RRH.

[0323] The RAN node can support one or more types of fronthaul interfaces. Different fronthaul interfaces respectively correspond to DUs and RUs with different functions. If the fronthaul interface between the DU and the RU is a common public radio interface (CPRI), the DU is configured to implement one or more of the baseband functions, and the RU is configured to implement one or more of the radio frequency functions. If the fronthaul interface between the DU and the RU is another interface, compared with the CPRI, some of the downlink and / or uplink baseband functions, for example, for the downlink, one or more of precoding, digital beamforming (BF), or inverse fast Fourier transform (IFFT) / CP addition, are moved from the DU to the RU for implementation, and for the uplink, one or more of digital beamforming (BF), or fast Fourier transform (FFT) / CP removal, are moved from the DU to the RU for implementation. In a possible implementation manner, this interface can be an enhanced common public radio interface (eCPRI). Under the eCPRI architecture, the splitting method between the DU and the RU is different, corresponding to different categories (Cat) of eCPRI, such as eCPRI Cat A, B, C, D, E, F.

[0324] Taking eCPRI Cat A as an example, for downlink transmission, with layer mapping as the segmentation, the DU is configured to implement layer mapping and one or more functions before it (i.e., one or more of encoding, rate matching, scrambling, modulation, layer mapping), while other functions after layer mapping (such as resource element (RE) mapping, digital BF, or one or more of IFFT / adding CP) are moved to the RU for implementation. For uplink transmission, with de-RE mapping as the segmentation, the DU is configured to implement demapping and one or more functions before it (i.e., one or more of decoding, de-rate matching, descrambling, demodulation, inverse discrete Fourier transform (IDFT), channel equalization, de-RE mapping), while other functions after demapping (such as digital BF or one or more of FFT / removing CP) are moved to the RU for implementation. It can be understood that for the function descriptions of DU and RU corresponding to various types of eCPRI, reference can be made to the eCPRI protocol, which will not be elaborated here.

[0325] In a possible design, the processing unit in the BBU for implementing baseband functions is called the baseband high (BBH) unit, and the processing unit in the RRU / AAU / RRH for implementing baseband functions is called the baseband low (BBL) unit.

[0326] In different systems, the CU (or CU-CP and CU-UP), DU, or RU may also have different names, but those skilled in the art can understand their meanings. For example, in an open radio access network (open-RAN, O-RAN or ORAN) system, the CU can also be called O-CU (open CU), the DU can also be called O-DU, the CU-CP can also be called O-CU-CP, the CU-UP can also be called O-CU-UP, and the RU can also be called O-RU. Any unit among the CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software modules and hardware modules. The network device in this application can be a virtualized device, for example, implemented through general-purpose hardware and instantiated virtualization functions, or dedicated hardware and instantiated virtualization functions. Among them, the general-purpose hardware can be a server, such as a cloud server.

[0327] In the embodiments of the present application, the device for implementing the functions of a network device may be a network device; it may also be a device capable of supporting the network device to implement such functions, such as a chip system, a hardware circuit, a software module, or a combination of a hardware circuit and a software module. This device may be installed in the network device or used in combination with the network device. In the embodiments of the present application, only the case where the device for implementing the functions of a network device is a network device is taken as an example for illustration, which does not limit the solutions of the embodiments of the present application.

[0328] The terminal device in the present application may also be referred to as a user equipment (UE), an access terminal, a user unit, a user station, a mobile station, a mobile platform, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communication device, a user agent, or a user device.

[0329] The terminal device can be a device that provides voice / data. For example, it can be a handheld device with wireless connection function, a vehicle-mounted device, etc. Currently, some examples of terminals are: mobile phone, tablet computer, laptop computer, palmtop computer, mobile internet device (MID), wearable device, virtual reality (VR) device, augmented reality (AR) device, wireless terminal in industrial control, wireless terminal in self-driving, wireless terminal in remote medical surgery, wireless terminal in smart grid, wireless terminal in transportation safety, wireless terminal in smart city, wireless terminal in smart home, cellular phone, cordless phone, session initiation protocol (SIP) phone, wireless local loop (WLL) station, personal digital assistant (PDA), a handheld device with wireless communication function, a computing device or other processing devices connected to a wireless modem, wearable device, terminal device in a 5G network or terminal device in a future evolved public land mobile network (PLMN), etc., devices in a zigbee network, devices in a Lora network, Bluetooth (BT slave), BLE slave, Wi-Fi station (station, STA), and so on. The embodiments of the present application are not limited thereto.

[0330] The terminal device can also be a terminal device in an IoT system, which can also be called an IoT node. IoT is an important part of the future development of information technology. Its main technical feature is to connect objects to the network through communication technology, so as to realize an intelligent network of human-machine interconnection and object-object interconnection. The connection can be through broadband technology or narrowband technology. IoT technology can achieve massive connection, deep coverage, and power saving of terminals through, for example, narrow band (NB) technology. IoT technology includes reflection communication technology, spread spectrum technology, ultra wide band (UWB), etc., which will not be elaborated here.

[0331] In addition, the terminal device may further include sensors such as intelligent printers, train detectors, gas stations, etc. The main functions include collecting data (for some terminal devices), receiving control information and downlink data from the network device, and transmitting electromagnetic waves to transmit uplink data to the network device.

[0332] By way of example and not limitation, in the embodiments of the present application, the terminal device may also be a wearable device. A wearable device, also known as a wearable intelligent device, is a general term for devices developed by applying wearable technology to the intelligent design of daily wear, such as glasses, gloves, watches, clothing, and shoes. A wearable device is a portable device that is directly worn on the body or integrated into the user's clothes or accessories. A wearable device is not only a hardware device, but also realizes powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable intelligent devices include those with complete functions and large sizes that can realize complete or partial functions without relying on a smart phone, such as smart watches or smart glasses, etc., and those that only focus on a certain type of application function and need to cooperate with other devices such as smart phones, such as various smart bracelets and smart jewelry for physical sign monitoring.

[0333] In the embodiments of the present application, the device for implementing the functions of the terminal device may be the terminal device or a device capable of supporting the terminal device to implement such functions, such as a chip system. This device may be installed in the terminal device or used in matching with the terminal device. In the embodiments of the present application, the chip system may be composed of chips or may include chips and other discrete devices. In the embodiments of the present application, only the case where the device for implementing the functions of the terminal device is the terminal device is taken as an example for illustration, which does not limit the solutions of the embodiments of the present application.

[0334] The terminal device in the present application may be a hardware device, or a software function running on dedicated hardware, or a software function running on general hardware, or a virtualized device. For example, it can be implemented through general hardware and instantiated virtualization functions, or dedicated hardware and instantiated virtualization functions. Among them, the general hardware may be a server, such as a cloud server.

[0335] The network device and / or the terminal device may be deployed on land, including indoor or outdoor, handheld or vehicle-mounted; may also be deployed on the water surface; and may also be deployed on airplanes, balloons, and satellites in the air. In the embodiments of the present application, the scenarios where the network device and the terminal device are located are not limited. Figure 1 It is a schematic diagram of the architecture of the communication system 10 to which the embodiments of the present application are applied. Figure 1 It shows a schematic diagram of a possible, non-limiting system architecture. As Figure 1As shown, the communication system 10 includes a radio access network (RAN) 100 and a core network 200. Optionally, the communication system 10 further includes the Internet 300. Among them, the RAN 100 may include at least one RAN node (such as Figure 1 110a and 110b in Figure 1 ), and may also include at least one terminal device (such as Figure 1 120a - 120j in

[0336] Figure 1 ). The terminal device can be connected to the radio access network device wirelessly. Between terminal devices and between radio access network devices, they can be connected to each other by wired or wireless means. The RAN node 110 is connected to the core network 200 by wireless or wired means. The core network devices in the core network 200 and the RAN nodes 110 in the RAN 100 can be different physical devices respectively, or the same physical device integrating the core network logic function and the radio access network logic function.

[0336] Figure 1 This is just a schematic diagram. The communication system 10 may further include other network devices, such as wireless relay devices and wireless backhaul devices, etc., which are not drawn in Figure 1 the figure.

[0337] The RAN 100 can be a cellular system related to the 3rd generation partnership project (3GPP), for example, 4G, 5G mobile communication systems, or an evolved system for the future (such as 6G mobile communication system). The RAN 100 can also be an ORAN, a cloud radio access network (CRAN), or a zigbee network system, or a wireless fidelity (Wi-Fi) system. The RAN 100 can also be a communication system integrating two or more of the above systems.

[0338] Among them, the RAN node can be a base station deployed in the air, for example, a satellite base station 110a; or it can be a base station deployed indoors, for example, a micro base station or an indoor station 110b. It should be understood that this application does not limit the specific technologies and specific device forms adopted by the radio access network device. For the convenience of description, the base station is used as an example of the radio access network device in the following description.

[0339] The terminal device can be a terminal device deployed in the air, such as Figure 1 a helicopter or a drone 120i in Figure 1Mobile phones 120a, 120e, 120f, and 120j, vehicle 120b, computer 110b, printer 120h, etc. in

[0340] Optionally, the terminal device can also be used as a RAN node. For example, a UE can act as a scheduling entity that provides sidelink signals between terminal devices in vehicle-to-everything (V2X), device-to-device (D2D), or peer-to-peer (P2P), etc.

[0341] The RAN node and the terminal device can be in a fixed position or movable. The RAN node and the terminal device can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; can also be deployed on the water surface; can also be deployed on airplanes, balloons, and artificial satellites in the air. Embodiments of the present application do not limit the application scenarios of the RAN node and the terminal device.

[0342] The roles of the RAN node and the terminal device can be relative. For example, Figure 1 The helicopter or drone 120i in can be configured as a RAN node. For those terminal devices 120j that access the RAN 100 through 120i, the terminal device 120i is a RAN node; but for the RAN node 110a, 120i is a terminal device, that is, the communication between 110a and 120i is through a radio air interface protocol. Of course, the communication between 110a and 120i can also be through the interface protocol between RAN nodes. At this time, relative to 110a, 120i is also a RAN node. Therefore, the RAN node and the terminal device can both be uniformly referred to as communication devices. Figure 1 110a, 110b, and 120a - 120j in can be referred to as communication devices with their respective corresponding functions, such as communication devices with RAN node functions or communication devices with terminal functions.

[0343] In the embodiments of the present application, the functions of the RAN node can also be executed by modules (such as chips) in the RAN node, or can be executed by a control subsystem including RAN node functions. The control subsystem including RAN node functions here can be a control center in application scenarios of the above terminals such as smart grids, industrial control, intelligent transportation, and smart cities. The functions of the terminal device can also be executed by modules (such as chips) in the terminal device, or can be executed by a device including terminal device functions. The present application does not limit this.

[0344] Furthermore, the present application can be applied to various specific communication scenarios. For example, point-to-point transmission between the RAN node and the terminal or between terminals (such asFigure 2 in (a), it is a point-to-point transmission between the RAN node and the terminal), multi-hop between the RAN node and the terminal (such as Figure 2 in (b) in Figure 2 in (c) in Figure 2 transmission), dual connectivity (DC) between multiple RAN nodes and the terminal (such as Figure 2 in (d) in

[0345] or multi-connection scenarios. It should be noted that the above specific communication application scenarios are only examples and do not impose limitations. In particular, from the perspective of services, the embodiments of the present application are applicable to many service scenarios, such as data encoding scenarios and uplink high-capacity scenarios in extended reality (XR) services. In addition, Figure 3 and Figure 4 to describe the transmitter architecture.

[0346] Figure 3 is a schematic diagram of the transmitter structure currently applied to terminal devices. As Figure 3As shown in the figure, the transmitter includes: a baseband chip, an inphase / quadrature (I / Q) modulator, and a linear PA. Among them, after receiving the signal to be transmitted, the baseband chip can perform baseband processing of the signal, such as channel coding, modulation, etc. The signals output by the baseband chip include: an I-channel baseband signal and a Q-channel baseband signal. The I / Q modulator can be used to perform I / Q modulation on the baseband signal. Exemplarily, the I / Q modulator includes: an I / Q generator, a mixer on the I-channel, and a mixer on the Q-channel. Among them, the I / Q generator (I / Q generator) generates an I-channel local oscillator signal and a Q-channel local oscillator signal respectively. The I-channel local oscillator signal can be input to the mixer on the I-channel, and the Q-channel local oscillator signal can be input to the mixer on the Q-channel. On the other hand, the I-channel baseband signal and the Q-channel baseband signal output from the baseband chip can be respectively input to the mixers on the two I / Q branches. The mixer on the I-channel can perform a mixing operation (or, up-conversion) on the I-channel baseband signal based on the input I-channel local oscillator signal. The mixer on the Q-channel can perform a mixing operation (or, up-conversion) on the Q-channel baseband signal based on the input Q-channel local oscillator signal and the Q-channel baseband signal. In this way, the I-channel baseband signal and the Q-channel baseband signal are shifted to the radio frequency band, and after superposition, a band-pass signal can be obtained. The linear PA can linearly amplify the band-pass signal and then output the amplified band-pass signal. Optionally, the transmitter further includes a PLL, which can be used to output a frequency signal for frequency conversion processing to the I / Q generator, lock the frequency signal at the local oscillator frequency, and have high accuracy. In other words, the phase-locked loop can provide a local oscillator signal.

[0347] In Figure 3 In the shown architecture, the I / Q modulator needs to generate an I-channel local oscillator signal and a Q-channel local oscillator signal through the I / Q generator, and also needs to perform up-conversion on the I-channel baseband signal and the Q-channel baseband signal respectively through the mixer. The circuit structure is complex, and it is necessary to rely on the mixer to realize the frequency band shift of the signal, which brings additional power consumption. In addition, linear power amplification also brings relatively large power consumption. Therefore, Figure 3 the shown transmitter structure will bring relatively large transmission power consumption.

[0348] Therefore, it is possible to make improvements to Figure 3 the shown transmitter structure in order to reduce the transmission power consumption from at least one of the two dimensions of up-conversion and power amplification.

[0349] Figure 4 is a schematic diagram of the transmitter structure applicable to the communication method provided in the embodiments of the present application. Figure 4 Shows three different transmitter structures: (a), (b), and (c).

[0350] Figure 4The transmitter shown in (a) includes: a baseband chip, an up-conversion module, and a non-linear PA. Among them, after receiving the signal to be transmitted, the baseband chip can perform baseband processing of the signal, such as channel coding, modulation, etc., and then output a baseband signal. The up-conversion module can directly frequency-modulate the carrier based on the baseband signal to shift the baseband signal to the radio frequency band and obtain a band-pass signal. The non-linear PA can perform non-linear power amplification on the band-pass signal and then output the power-amplified band-pass signal. By way of example and not limitation, the up-conversion module may include: a PLL (as shown in the figure), a VCO, or a DCO. It can be seen that Figure 4 In (a), by directly frequency-modulating the carrier, it avoids shifting the signal band through a mixer in I / Q modulation, which can save power consumption; and compared with a linear PA, the non-linear PA can also save a large amount of power consumption. Therefore, the transmission power consumption is reduced from two dimensions: up-conversion and power amplification.

[0351] Figure 4 The transmitter shown in (b) includes: a baseband chip, an I / Q modulator, and a non-linear PA. Among them, after receiving the signal to be transmitted, the baseband chip can perform baseband processing of the signal, such as channel coding, modulation, etc., and then output an I-channel baseband signal and a Q-channel baseband signal. The I-channel baseband signal and the Q-channel baseband signal can be respectively input into the mixers on the I-channel and the Q-channel. The I / Q generator can generate an I-channel local oscillator signal and a Q-channel local oscillator signal, which are respectively input into the mixers on the I-channel and the Q-channel. The mixers on the I / Q two channels can perform mixing operations respectively based on the input I-channel baseband signal, I-channel local oscillator signal, Q-channel baseband signal, and Q-channel local oscillator signal. In this way, the I / Q two-channel baseband signals are shifted to the radio frequency band and superimposed to obtain a band-pass signal. The non-linear PA can perform non-linear power amplification on the band-pass signal and then output the power-amplified band-pass signal. It can be seen that Figure 4 In (b), by performing non-linear power amplification on the band-pass signal, the transmission power consumption can be reduced from the dimension of power amplification.

[0352] Figure 4 The transmitter shown in (c) includes: a baseband chip, an up-conversion module (PLL shown in the figure), and a linear PA. Among them, after receiving the signal to be transmitted, the baseband chip can perform baseband processing of the signal, such as channel coding, modulation, etc., and then output a baseband signal. The up-conversion module can directly frequency-modulate the carrier based on the baseband signal to shift the baseband signal to the radio frequency band and obtain a band-pass signal. The linear PA can perform non-linear power amplification on the band-pass signal and then output the power-amplified band-pass signal. It can be seen that Figure 4 In (c), by directly frequency-modulating the carrier, it avoids shifting the signal band through a mixer in I / Q modulation, thereby reducing the transmission power consumption from the dimension of up-conversion.

[0353] Those skilled in the art know that whether it is direct frequency modulation or non-linear PA, there are relatively strict requirements for the waveform: that is, a constant envelope waveform with a PAPR of 0 dB needs to be used for data transmission. However, the current cellular network uses OFDM technology. To avoid interference between OFDM symbols, a guard period is usually inserted in the form of CP between OFDM symbols. And CP is usually formed by copying the signal at the tail of the OFDM symbol to the head. Even if some continuous phase modulation techniques are used to ensure the phase continuity of the signal itself, it is still impossible to ensure the phase continuity between CP and the signal behind it, thus unable to ensure a constant waveform envelope.

[0354] In view of this, the present application provides a method that expands based on the symbol sequence obtained by modulation. By adding several additional symbols, the phase difference between the head and the tail of the modulation symbol sequence obtained by modulation is an integer multiple of 2π, that is, the head and the tail are phase continuous. Therefore, the body signal of the baseband signal generated from this modulation symbol sequence can also satisfy head and tail phase continuity, and thus it is beneficial to obtain a phase continuous waveform.

[0355] On this basis, if some modulation methods that can ensure phase continuity are used, such as CPM or LFM, etc., a phase continuous modulation symbol sequence can be obtained. Combining these modulation techniques that can ensure phase continuity with the method provided by the present application, the obtained modulation symbol sequence can satisfy: phase continuity and head and tail phase continuity. Thus, the baseband signal generated therefrom can satisfy phase continuity. And CPM and LFM themselves are modulation methods that modulate the information to be transmitted on the phase or frequency, and the amplitude remains unchanged during the modulation process. Therefore, a constant envelope waveform with phase continuity and constant amplitude can be obtained.

[0356] Moreover, the present application further considers the situation of sending data on multiple consecutive OFDM symbols. By expanding the symbol sequence to be transmitted, the modulation symbol sequence obtained after modulating the expanded symbols satisfies double head and tail phase continuity. That is, if the modulation symbol sequence is divided into two parts, and the length of the second half is not less than the length of CP, that is, K 1 modulation symbols, that is, the number of modulation symbols included in the second half is not less than K 1 ones, and these two parts respectively satisfy phase head and tail continuity, where K 1is a positive integer. In this way, the phase at the beginning and end of the modulated symbol sequence obtained after each OFDM symbol is extended and modulated is also continuous with the initial phase of the OFDM symbol, that is, the phase difference satisfies an integer multiple of 2π. In this way, by controlling the initial phase, the initial phase of the signal transmitted on each OFDM symbol can be controlled, so that the signal on each OFDM symbol is not only phase continuous on this OFDM symbol, but also phase continuous with the signals on the previous and subsequent OFDM symbols. Thus, a constant envelope waveform can be obtained on a continuous plurality of OFDM symbols. In this way, this constant envelope waveform can be applied to the transmitter structure shown in Figure 4 above, or rather, the communication device can use a processing method with lower transmission power consumption to transmit signals, so as to achieve the effects of saving power and increasing standby life.

[0357] To better understand the embodiments of the present application, the following Figure 5 briefly describes the processing process after the signal reaches the physical layer.

[0358] Figure 5 The signal processing process shown above can be performed by one of the terminal device or the network device as the sending end, or one of the terminal device or the network device can be used as the receiving end, and the present application does not limit this.

[0359] As Figure 5 shown, the physical layer of the sending end divides the information sequence from the upper layer (such as the medium access control (MAC) layer) into multiple transport blocks (TBs), and adds a cyclic redundance check (CRC) to each transport block. If the size of the transport block after adding the check exceeds the maximum code block length, the transport block needs to be divided into several code blocks (CBs).

[0360] The sending end can perform channel coding on each code block, such as polar code coding, to obtain the corresponding coded code block. Rate matching is performed on the coded code block, and the code blocks after rate matching are concatenated to form a codeword (CW).

[0361] The sending end can scramble the codeword to generate scrambled bits. The scrambled bits are modulated to obtain modulated symbols. After the modulated symbols are RE mapped, they are mapped to multiple REs, and thus the values carried on each RE can be obtained. Based on the values carried on these REs, the sending end can generate an OFDM baseband signal. The OFDM baseband signal can be up-converted to obtain a bandpass signal, and after operations such as power amplification, the bandpass signal is transmitted through the transmitting antenna.

[0362] The receiving end can receive signals through a receiving antenna. After receiving the bandpass signal from the transmitting end, the receiving end can perform down-conversion on the bandpass signal to obtain the first OFDM baseband signal. Thereafter, the physical layer of the receiving end can successively perform operations such as demapping RE, demodulation, descrambling, rate dematching, and channel decoding on the signal, so as to obtain the information sequence.

[0363] Optionally, after the receiving end completes demapping RE and before demodulation, channel equalization can also be performed. Channel equalization is based on the channel obtained from channel estimation, and by using an equalization algorithm to remove the influence of the channel, so as to ensure the correct demodulation of the signal. It can be understood that the information sequence received by the receiving end corresponds to the information sequence to be transmitted by the transmitting end.

[0364] Optionally, after the transmitting end completes modulation and before RE mapping, layer mapping and precoding can also be performed. For example, the transmitting end can map modulation symbols to multiple layers. After layer mapping, the modulation symbols are precoded to obtain the precoded signal. The precoded signal is mapped to multiple REs through RE mapping. Correspondingly, after the receiving end completes demapping RE and before channel equalization, layer demapping and precoding can also be performed, and then channel equalization can be performed.

[0365] Since Figure 5 the specific implementation manners of each step in rd can be implemented through existing technologies. For details, reference can be made to the relevant chapters in the technical specification (TS) 38.211 of the 3rd Generation Partnership Project (3GPP), which will not be elaborated here.

[0366] Figure 5 Only as an example, in other standards related to communication technologies, the signal processing process may include some of these operations. For example, in ZigBee technology, the physical layer operations of the transmitting end may include encoding, modulation, transmission, etc., and the physical layer operations of the receiving end may include receiving, demodulation, decoding, etc.

[0367] In different communication technologies, the operations of the transmitting end and the physical layer can refer to their respective existing technologies, such as referring to relevant standards, and will not be exemplified one by one.

[0368] The communication method provided by this application will be described in detail below with reference to the accompanying drawings. In the following embodiments, two different implementation manners for implementing the communication method provided by this application are provided by taking the processes shown in Figure 6 and Figure 15 as examples respectively. Among them,Figure 6 In the shown process, a first communication device (such as a terminal device) can, after obtaining a first symbol sequence to be transmitted, expand it to obtain a third symbol sequence, and then perform RE mapping after modulating the third symbol sequence, and generate a first OFDM baseband signal based on the second symbol sequence obtained from the RE mapping. This process can be similar to the process of generating an OFMD baseband signal defined in the current standard. Figure 15 In the shown process, the first communication device can pre-generate a first CP sequence corresponding to the CP of the first OFDM baseband signal before generating the first OFDM baseband signal. As can be seen in comparison, in Figure 6 In the shown process, during the generation process of the first OFDM baseband signal, the first communication device generates the CP of the first OFDM baseband signal without pre-generating the first CP sequence.

[0369] In addition, Figure 6 and Figure 15 Taking the terminal device sending N symbols to be transmitted to the network device as an example of data transmission respectively, the communication method provided in this application is described. Among them, the terminal device is an example of the first communication device, and the network device is an example of the second communication device. That is to say, the terminal device can be replaced by the first communication device, and the network device can be replaced by the second communication device. And it should be understood that Figure 6 and 15 The methods shown in and are not only applicable to the terminal device sending data to the network device, but also can be used for the network device to send data to the terminal device. That is to say, the first communication device can be the network device, and the second communication device can be the terminal device; it can also be used for communication between terminal devices. That is to say, both the first communication device and the second communication device are terminal devices. This application does not make any limitations in this regard. In addition, the above-mentioned terminal device can also be replaced by components used for the terminal device, such as chips, chip systems, processors, etc., and can also be replaced by logical modules or software that can implement all or part of the functions of the terminal device. The above-mentioned network device can also be replaced by components used for the network device, such as chips, chip systems, processors, etc., and can also be replaced by logical modules or software that can implement all or part of the functions of the network device.

[0370] The following describes these two implementation manners in conjunction with the accompanying drawings respectively.

[0371] Figure 6 is a schematic flowchart of a communication method provided by an embodiment of this application.

[0372] Figure 6The method 600 shown may include steps 601 to 610. Among them, steps 601 to 606 are processes executed by the terminal device, and steps 606 to 610 are processes executed by the network device. Exemplarily, steps 601 to 603 may be executed by the baseband chip of the terminal device, steps 604 to 605 may be executed by the radio frequency chip of the terminal device, where step 604 may be executed by the up-conversion module in the radio frequency chip, step 605 may be executed by the power amplifier in the radio frequency chip, and the sending operation in step 606 may be executed by the antenna (such as a transmitting antenna) of the terminal device. The receiving operation in step 606 may be executed by the antenna (such as a receiving antenna) of the network device, step 607 may be executed by the radio frequency chip of the network device, and steps 608 to 610 may be executed by the baseband chip of the network device.

[0373] The following details each step in method 600.

[0374] In step 601, the terminal device obtains a first symbol sequence, which includes N symbols to be transmitted.

[0375] Exemplarily, the terminal device (specifically, the baseband chip in the terminal device) may perform baseband processing on the information to be transmitted from the higher layer, such as channel coding, rate matching, modulation, etc., to obtain N symbols to be transmitted. Among them, the modulation may include, but is not limited to, one-dimensional modulation methods such as PAM, π / 2-BPSK, BPSK, QPSK, etc.

[0376] Among them, the one-dimensional modulation method refers to modulation performed in one of the three dimensions of amplitude, phase, or frequency. Through a predefined mapping relationship, the bit sequence to be transmitted is modulated to output a value in a certain dimension in the complex plane, or in other words, to output a real number or a pure imaginary number.

[0377] In step 602, the terminal device obtains a second symbol sequence based on the first symbol sequence.

[0378] In this embodiment, the terminal device may obtain the second symbol sequence through modulation.

[0379] As mentioned above, if modulation is directly performed based on the first symbol sequence, the OFDM baseband signal generated by the obtained modulation symbol sequence may have a phase jump between the CP and the signal body, resulting in an unconstant envelope. Therefore, the terminal device may add several extended symbols on the basis of the first symbol sequence, and design the extended symbols to obtain a self-loop of the phase at the beginning and end of the modulation symbol sequence, so that the phase between the CP and the signal body of the generated OFDM baseband signal is continuous.

[0380] Optionally, step 602 includes:

[0381] Step 6021: The terminal device determines a third symbol sequence based on the first symbol sequence;

[0382] Step 6022: The terminal device modulates based on the third symbol sequence to obtain a fourth symbol sequence;

[0383] Step 6023: The terminal device maps the modulation symbols in the fourth symbol sequence to the REs to obtain a second symbol sequence.

[0384] Among them, the third symbol sequence includes the above-mentioned N symbols to be transmitted and M extended symbols. In step 6021, the third symbol sequence can be calculated according to the modulation method and the first symbol sequence. That is, by inserting M extended symbols before, among, or after the N symbols to be transmitted, the modulation symbol sequence (i.e., the fourth symbol sequence described later) obtained after modulating the third symbol sequence obtained after inserting M extended symbols has the characteristic of self-looping phase at the head and tail.

[0385] It should be noted that steps 6021 and 6022 are not necessarily executed separately, and it is also possible to execute them synchronously. In the text, they are only split into two steps for easy understanding. For example, the terminal device can modulate while determining the third symbol sequence, rather than necessarily modulating after determining the third symbol sequence.

[0386] If directly modulating based on the first symbol sequence, it may cause the phase at the head and tail of the modulation symbol sequence obtained by modulation to be discontinuous, and further cause the CP of the OFDM baseband signal generated from this modulation symbol sequence to be discontinuous with the main body signal. Therefore, the terminal device can add a certain number (such as M) of extended symbols on the basis of the first symbol sequence, and realize the self-looping phase at the head and tail of the fourth symbol sequence through the design of the extended symbols, so that the CP of the first OFDM baseband signal generated based on this fourth symbol sequence is phase continuous with the signal main body, that is, a phase continuous waveform is obtained.

[0387] It can be understood that when M is zero, the third symbol sequence is the same as the first symbol sequence; when M is greater than zero, the third symbol sequence is different from the first symbol sequence. The third symbol sequence is a sequence obtained by adding one or more extended symbols while keeping the order of the N symbols to be transmitted in the first symbol sequence unchanged.

[0388] As an example rather than a limitation, the modulation in this application is continuous phase modulation. Exemplarily, the modulation includes CPM or LFM. Since CPM belongs to phase modulation and LFM belongs to frequency modulation, the modulation described in this article can also be called phase or frequency modulation.

[0389] Next, step 6021 will be described in conjunction with two methods, namely CPM and chirp, respectively.

[0390] CPM:

[0391] A non - linear modulation scheme that carries information through the phase of a carrier wave. Its transmitted signal has the characteristics of constant envelope and continuous phase change. Assume that the first symbol sequence a is: {a 1 , a 2 , a 3 , ……, a N}, which includes a total of N symbols to be transmitted. The band - pass waveform s(t, a) obtained by performing CPM on the first symbol sequence a satisfies:

[0392]

[0393] where, represents the phase of the first symbol sequence a at time t. Connecting the phases at different times can obtain the base - band waveform, satisfies: E is the energy symbol; T is the duration of each symbol; for the first symbol sequence a, the value of t satisfies: 0 ≤ t ≤ NT; f c is the carrier frequency; is the initial phase of the carrier; h is the modulation index, or the modulation exponent of the CPM signal; a i is the i - th symbol to be transmitted in the first symbol sequence a; g(t) is the frequency pulse - shaping function, satisfying: q(t) represents the phase pulse - shaping function; is the initial phase of the CPM.

[0394] If M additional extended symbols are added to the symbol sequence a to obtain the symbol sequence then the symbol sequence as long as the phase difference between the starting position and the ending position is an integer multiple of 2π, it can satisfy the property of self - cycling of the head and tail phases.

[0395] In the embodiments of the present application, assume that the first symbol sequence is the aforementioned symbol a, and the third symbol sequence is the symbol sequence Then, performing CPM on the third symbol sequence , the value of t satisfies: 0 ≤ t ≤ (N + M)×T, and the phase of the starting position of the obtained fourth symbol sequence can be expressed as The fourth symbol sequence The phase of the ending position can be expressed as, The phase difference between the starting position and the ending position of the fourth symbol sequence is an integer multiple of 2π, which can be expressed as: k 1 is an integer.

[0396] To better understand the relationship between the M extended symbols and the head and tail phase self - circulation, the following is illustrated with an example in conjunction with Figure 7 . Figure 7 This is an example of the third symbol sequence provided by the embodiment of the present application. The phase change of the third symbol sequence is shown in this figure. For easy distinction in the figure, the N symbols to be transmitted and their corresponding phase changes are represented by solid lines, and the M extended symbols and their corresponding phase changes are represented by dashed lines.

[0397] Assume N = 3. The N symbols to be transmitted in the first symbol sequence can be obtained by PAM, which are: +1, +1, -1. Assume the mapping relationship between the symbols obtained by PAM and the phase difference of CPM is: the symbol with a value of +1 corresponds to a phase difference of +90°, and the symbol with a value of -1 corresponds to a phase difference of -90°, and the initial phase of CPM is 0°. Then, based on this mapping relationship, the phase changes of the symbols of the first symbol sequence passing through CPM are as follows: 0° → 90° → 180° → 90°. It can be seen that if no additional extended symbols are added to the first symbol sequence, the phase difference between the phase of the end position +90° and the phase of the start position 0° of the first symbol sequence is 90°, showing a jump. If it is desired that the difference between the head and tail phases is an integer multiple of 2π, then one extended symbol -1 can be added to the tail of the N symbols to be transmitted, and the following third symbol sequence is obtained: +1, +1, -1, -1. By adding the extended symbol -1, the phase of the end position can be adjusted from 90° to 0° through the phase difference of -90°, and the difference from the phase of the start position is an integer multiple of 2π. Thus, the (N + M) symbols in the third symbol sequence are: +1, +1, -1, -1.

[0398] Of course, the way of adding one extended symbol to the tail of the N symbols to be transmitted is only one possible way, not the only one. For example, more extended symbols can also be added to the tail of the N symbols to be transmitted, or one or more extended symbols can be added to the head or other positions of the N symbols to be transmitted, and so on.

[0399] It should be understood that the formula for the baseband waveform of CPM above is only an example, and those skilled in the art can make equivalent replacements or simple transformations to it to obtain other formulas, and the present application includes but is not limited to this.

[0400] LFM:

[0401] An extended - spectrum modulation technology that does not require a pseudo - random coding sequence. An LFM signal refers to a signal whose instantaneous frequency changes linearly with time. The band - pass signal s(t,a) obtained by performing LFM on the symbol sequence a satisfies:

[0402]

[0403] Among them, represents the phase of the symbol sequence a at time t. By connecting the phases at different times, the baseband waveform can be obtained. For the symbol sequence a, the value of t satisfies: 0 ≤ t ≤ NT; A is the amplitude; f c is the carrier frequency; F represents the frequency modulation slope of LFM, 1 / T represents the information bandwidth, FT >> 1, which is the maximum peak value output by the matched filter; is the initial phase of the carrier.

[0404] Similar to CPM, if the phase difference between any two adjacent times of the baseband waveform is an integer multiple of 2π, the baseband waveform satisfies phase continuity, and the bandpass waveform is also phase continuous. Therefore, if M extended symbols are additionally added to the symbol sequence a to obtain the symbol sequence then this symbol sequence as long as the phase difference between the starting position and the ending position is an integer multiple of 2π, it can satisfy the characteristic of self-looping of the head and tail phases.

[0405] In the embodiments of the present application, it is assumed that the first symbol sequence is the aforementioned symbol a, and the third symbol sequence is the symbol sequence then for the third symbol sequence performing LFM, the value of t satisfies: 0 ≤ t ≤ (N + M) × T, and the phase of the starting position of the obtained fourth symbol sequence can be expressed as The fourth symbol sequence the phase of the ending position can be expressed as, the phase difference between the starting position and the ending position of the fourth symbol sequence is an integer multiple of 2π, which can be expressed as: k 1 is an integer.

[0406] For the description of the M extended symbols and the self-looping of the head and tail phases, reference can be made to the examples in the foregoing in combination with Figure 7 and LFM is similar thereto and will not be elaborated.

[0407] It should be understood that the formula for the baseband waveform of LFM above is only an example, and those skilled in the art can make equivalent substitutions or simple transformations to it to obtain other formulas, and the present application includes but is not limited to this.

[0408] In step 6022, the terminal device can perform modulation based on the third symbol sequence. The process of the terminal device performing modulation based on the third symbol sequence can be implemented through various possible implementation manners, and different implementation manners will be described in detail below with reference to the accompanying drawings.

[0409] One possible implementation manner of step 6022 is as Figure 8 shown, modulating the third symbol sequence to obtain a fourth symbol sequence.

[0410] That is to say, the third symbol sequence is used as the input of modulation, and the third symbol sequence is modulated. The output of modulation is the fourth symbol sequence.

[0411] Since the modulation method provided in this application is for ensuring phase - continuous modulation, the (N + M) modulated symbols obtained after modulation are continuous. Only by sampling them can they be stored in the digital system. Therefore, after modulation, each modulated symbol obtained by modulation can also be sampled. Sampling can be regarded as an independent operation. As shown in the figure, sampling is performed after modulation. Or, sampling can also be regarded as part of modulation. In this case, the sampling in the figure can be combined with modulation. This application does not make a limit on this.

[0412] Assume that the sampling rate is S, and S is a positive integer. Then, S sample points are sampled for each modulated symbol, and each modulated symbol can be recorded by the S sample points obtained by sampling. Since the third symbol sequence includes (N + M) symbols, (N + M) modulated symbols can be obtained after modulation. Therefore, (N + M)×S time - domain sample points can be obtained by sampling. In the embodiments of this application, the fourth symbol sequence can refer to the continuous (N + M) modulated symbols obtained by modulation, or can refer to the (N + M)×S sample points obtained by sampling. The (N + M) modulated symbols and the (N + M)×S time - domain sample points can be regarded as two different forms of the fourth symbol sequence.

[0413] Another possible implementation manner of step 6022 is as Figure 9 shown. The N symbols to be transmitted and the M extended symbols in the third symbol sequence are modulated respectively to obtain N modulated symbols and M modulated symbols. According to the positions of the M extended symbols in the third symbol sequence, the M modulated symbols are inserted into the N modulated symbols, and at least some of the modulated symbols in the N modulated symbols are phase - compensated so that the phases of the (M + N) modulated symbols after inserting the M modulated symbols are continuous (which can correspond to Figure 9 the splicing operation in), and thus the second symbol sequence can be obtained.

[0414] Since this application does not limit the positions of the M modulated symbols in the third symbol sequence, the M modulated symbols can be continuous and located before or after the N symbols to be transmitted. Or, the M modulated symbols can also be continuously or discretely distributed among the N symbols to be transmitted. Due to the characteristic of the cumulative phase of CPM itself, when the M modulated symbols are inserted into the N symbols to be transmitted, it is necessary to consider the phase continuity between the inserted M modulated symbols and the N modulated symbols. Therefore, phase compensation is required.

[0415] For easy understanding, the process of phase compensation is illustrated by an example below.

[0416] In one example, assume N = 3, M = 1. The positions of the M extended symbols in the third symbol sequence are before the N symbols to be transmitted. For example, it is denoted as: a ex1 , a 1 , a 2 , a 3 , a 1 to a 3 are the symbols to be transmitted, a ex1 is the extended symbol. Taking the extended symbol a ex1 as the boundary, the third symbol sequence can be divided into two parts, denoted as: a 1 (including a ex1 ) and a 2 (including a 1 , a 2 , a 3 ). Taking CPM as an example, if CPM is performed on a 1 and a 2 respectively to obtain M modulated symbols corresponding to a 1 and N modulated symbols corresponding to a 2 , the phases of the N modulated symbols can be phase-compensated according to the difference between the phase at the end position of the M modulated symbols and the phase at the start position of the N modulated symbols, so that the phase difference between the N modulated symbols and the M modulated symbols is an integer multiple of 2π.

[0417] For example, in this example, assume the initial phase of CPM is The phase at the end position of the M modulated symbols is: The phase at the start position of the N modulated symbols is: The difference between the phase at the end position of the M modulated symbols and the phase at the start position of the N modulated symbols is: Therefore, the phases of the N modulated symbols can be compensated according to this phase difference. The phase at the start position of the N modulated symbols obtained after compensation is: That is, The phase at the end position of the N modulated symbols obtained after compensation is: k 2 is an integer.

[0418] In another example, assume N = 3, M = 2. The M extended symbols are discretely distributed in the third symbol sequence. One extended symbol is after the first symbol to be transmitted among the N symbols to be transmitted, and the other extended symbol is after the N symbols to be transmitted. For example, it is denoted as: a 1 , a ex1 , a 2 , a 3 , a ex2 , a 1 to a 3 are the symbols to be transmitted, aex1 and a ex2 are extension symbols. Taking the extension symbols a ex1 and a ex2 as boundaries, the third symbol sequence can be divided into three parts, which are respectively denoted as a 1 (including a 1 , a ex1 ), a 2 (including a 2 , a 3 ) and a 3 (including a ex2 ). Taking CPM as an example, if CPM is respectively performed on a 1 , a 2 and a 3 , 1 modulation symbol corresponding to a 1 is obtained respectively (for easy distinction and explanation, denoted as symbol block 1), 2 modulation symbols corresponding to a 2 are obtained (for easy distinction and explanation, denoted as symbol block 2), and 1 modulation symbol corresponding to a 3 is obtained (for easy distinction and explanation, denoted as symbol block 3). Except for the part at the very front, the phase of the modulation symbols in each of the remaining two parts needs to be phase-compensated according to the difference between the phase at the end position of the previous part and the phase at the start position of the next part. For example, the phase of symbol block 2 needs to be compensated according to the difference between the phase at the end position of symbol block 1 and the phase at the start position of symbol block 2, and the phase of symbol block 3 needs to be compensated according to the difference between the phase at the end position of symbol block 2 after phase compensation and the phase at the start position of symbol block 3.

[0419] For example, in this example, assuming the initial phase of CPM is the phase at the end position of symbol block 1 is the phase at the start position of symbol block 2 is: the difference between the phase at the start position of symbol block 2 and the phase at the end position of symbol block 1 is: Therefore, the phase of symbol block 2 can be compensated according to this phase difference, and the phase at the start position of symbol block 2 obtained after compensation is: the phase at the end position of symbol block 2 is: k 3 is an integer. After phase compensation is performed on symbol block 2, the phase of symbol block 3 can be compensated according to the difference between the phase at the end position of symbol block 2 after compensation and the phase at the start position of symbol block 3. The phase at the start position of symbol block 3 is the difference between the phase at the end position of symbol block 3 and the phase at the start position of symbol block 2 after compensation is: k 4is an integer. Therefore, the phase of symbol block 3 can be compensated according to this phase difference, and the phase at the starting position of symbol block 3 obtained after compensation is: The phase at the ending position of symbol block 3 is:

[0420] The process of phase compensation has been illustrated by examples in combination with different values of M and different positions in the third symbol sequence above. Those skilled in the art can perform phase compensation based on the same concept, for any value of M, and at any position in the third symbol sequence. For the sake of brevity, no further examples are given here. In addition, the above examples only provide one possible way of phase compensation, and this application does not exclude the possibility of performing phase compensation through other means to obtain a fourth symbol sequence with continuous phase.

[0421] Similar to Figure 8 and Figure 9 After modulating N symbols to be transmitted and M extended symbols, each modulated symbol obtained by modulation can also be sampled. Sampling can be regarded as an independent operation. As shown in the figure, sampling is performed after modulation, or sampling can also be regarded as part of modulation. In this case, the sampling in the figure can be combined with modulation, and this application does not make any limitation in this regard.

[0422] Assuming the sampling rate is S, then N×S sample points and M×S sample points can be obtained by sampling the N modulated symbols and M modulated symbols respectively. The process of inserting M modulated symbols into N modulated symbols above, that is, the process of inserting M×S sample points into N×S sample points, is similar in implementation and will not be elaborated.

[0423] As described above in combination with Figure 8 and Figure 9 Two possible implementation manners of step 6022 are shown. These implementation manners are only examples and should not constitute any limitation to this application. This application does not limit the specific implementation manner of step 6022.

[0424] In several implementation manners exemplified above, the fourth symbol sequence can be recorded by sample points. Among them, the sampling rate S can be predefined, configured by the network device, or determined by the terminal device. This application does not make any limitation in this regard.

[0425] If the sampling rate S is configured by the network device, optionally, the method further includes: the terminal device receives second information from the network device, or in other words, the network device sends second information to the terminal device, and this second information is used to indicate the sampling rate S. The network device can indicate the sampling rate S to the terminal device through the second information, so as to facilitate the network device to determine the number of subcarriers used to transmit the second symbol sequence, and then correctly demodulate the received signal.

[0426] If the sampling rate S is determined by the terminal device, optionally, the method further includes: the terminal device sends second information to the network device, or in other words, the network device receives the second information from the terminal device, and the second information is used to indicate the sampling rate S. The terminal device can also determine the sampling rate S by itself, for example, according to factors such as transmission rate and demodulation performance, and then indicate it to the network device through the second information, so that the network device can correctly demodulate the received signal.

[0427] After the terminal device obtains the fourth symbol sequence through modulation, it can perform step 6023 to map each modulation symbol in the fourth symbol sequence to the RE, so as to obtain the value carried on each RE. For the convenience of distinction and description in the text, the symbol sequence after RE mapping is denoted as the second symbol sequence, and the symbols in the second symbol sequence are obtained by mapping the (N + M) modulation symbols in the aforementioned fourth symbol sequence to the RE.

[0428] The fourth symbol sequence can be understood as a single carrier (SC) (CP-SC) symbol based on the CP. After converting a CP-SC symbol to the frequency domain, it is mapped to multiple subcarriers to obtain the DFT-s-OFDM waveform.

[0429] It should be understood that in the baseband chip, RE mapping mainly refers to the frequency domain mapping in the baseband. Therefore, the frequency domain mapping can be regarded as the determination of the relative positions of each subcarrier when the signal is mapped to the frequency domain resources. In step 604 later, the terminal device will move the signal from the baseband to the target frequency band, which will not be elaborated here for the time being.

[0430] It should be noted that RE mapping is a step corresponding to the 3GPP standard. For the specific implementation process, reference can be made to the relevant chapter on RE mapping in TS 38.211, which will not be elaborated here. In this application, mapping the (N + M) modulation symbols in the fourth symbol sequence to the RE includes, but is not limited to, RE mapping. Since the fourth symbol sequence is a symbol sequence in the time domain and RE mapping is performed in the frequency domain, the (N + M) modulation symbols in the fourth symbol sequence can be converted to the frequency domain for RE mapping. In other words, mapping the (N + M) modulation symbols in the fourth symbol sequence to the RE includes, in addition to RE mapping, operations such as converting the (N + M) modulation symbols in the fourth symbol sequence to the frequency domain. For the specific details, reference can be made to the detailed description of this step in combination with Method 1 and Method 2 below.

[0431] Method 1: After converting the fourth symbol sequence to the frequency domain, perform frequency domain interleaved mapping to obtain the second symbol sequence.

[0432] As previously mentioned, the fourth symbol sequence includes (N + M) × S samples. Since the fourth symbol sequence is a time-domain signal, the (N + M) × S samples are time-domain samples. Converting the (N + M) × S time-domain samples to the frequency domain yields (N + M) × S frequency-domain samples. Performing RE mapping on the (N + M) × S frequency-domain samples such that each frequency-domain sample is mapped to a subcarrier, each of the above-mentioned (N + M) × S subcarriers can be used to transmit a frequency-domain sample. Mapping the (N + M) × S frequency-domain samples to (N + M) × S subcarriers enables determination of the value carried by each RE, resulting in the second symbol sequence mentioned above. A possible form of the second symbol sequence is (N + M) × S frequency-domain samples carried on (N + M) × S subcarriers. Starting from the first sample of the (N + M) × S frequency-domain samples and proceeding sequentially, every S frequency-domain samples correspond to one of the (N + M) modulation symbols of the fourth symbol sequence. Viewed in the frequency domain, the (N + M) × S frequency-domain samples can also be referred to as (N + M) × S modulation symbols.

[0433] Among them, the methods for converting a signal from the time domain to the frequency domain may include, but are not limited to, FFT, discrete Fourier transform (DFT), etc., and the methods for converting a signal from the frequency domain to the time domain may include, but are not limited to, IFFT, IDFT, etc. This application does not make any limitations in this regard.

[0434] Optionally, the (N + M) × S subcarriers are continuous. The (N + M) × S subcarriers being continuous specifically may mean that the numbers of the (N + M) × S subcarriers are continuous. The above-mentioned (N + M) × S frequency-domain samples are mapped to (N + M) × S consecutive subcarriers.

[0435] Optionally, the (N + M) × S subcarriers are in a comb shape, and the subcarrier offset between every two adjacent teeth is equal. In other words, the (N + M) × S subcarriers are discontinuous, or rather, the numbers of the (N + M) × S subcarriers are not continuous. The subcarrier offset between every two adjacent teeth being equal means that the number of subcarriers by which the (N + M) × S subcarriers are offset between every two subcarriers is equal. That is to say, the (N + M) × S subcarriers are equally spaced.

[0436] Assume the subcarrier offset is Z p (Z p is a positive integer), that is, there are Z p subcarriers between every two adjacent teeth that are not used to transmit the above-mentioned N symbols to be transmitted. The Z p subcarriers can be empty or can be used to transmit other signals. This application does not make any limitations in this regard. It can be understood that when Z p= 1 indicates that the (N + M) × S sub - carriers are continuous; when Z p > 1 indicates that the (N + M) × S sub - carriers are discontinuous.

[0437] Figure 10 shows a schematic diagram of (N + M) × S sub - carriers. Figure 10 shows a plurality of continuous sub - carriers, where the black squares represent the sub - carriers for carrying the first OFDM baseband signal, which are examples of the above - mentioned (N + M) × S sub - carriers and can be abbreviated as data sub - carriers, and the white squares represent the sub - carriers not used for carrying data, abbreviated as empty sub - carriers. The black squares are equally spaced among the plurality of sub - carriers, in a comb - like shape, and the sub - carrier offset Z p = 2.

[0438] When the frequency - domain resources allocated by the network device to the terminal device contain more than (N + M) × S sub - carriers, based on the above design, (N + M) × S frequency - domain samples can be equally spaced and mapped onto the frequency - domain resources. This way of frequency - domain mapping can be called frequency - domain interleaved mapping. Briefly speaking, frequency - domain interleaved mapping includes frequency - domain interleaving and RE mapping. Frequency - domain interleaving and RE mapping can be carried out synchronously, or frequency - domain interleaving first and then RE mapping, or RE mapping first and then frequency - domain interleaving. This application does not make a limitation on this.

[0439] Through frequency - domain interleaved mapping, there is one or more empty sub - carriers between every two sub - carriers carrying the above - mentioned frequency - domain samples, and the number of empty sub - carriers between every two adjacent data sub - carriers is equal. Among them, zeros can be inserted on the empty sub - carriers between every two adjacent data sub - carriers. Therefore, from the number of frequency - domain samples (N + M) × S and the sub - carrier offset Z p , the number of time - domain points that can be formed is (N + M) × S × Z p . Among them, (N + M) × S time - domain samples are obtained by sampling the (N + M) modulation symbols in the fourth symbol sequence, and the other (N + M) × (Z p −1) time - domain samples are obtained by inserting zeros in the frequency domain. It can be understood that Z p being 1 means no zero insertion in the frequency domain, or in other words, no frequency - domain interleaving. That is to say, frequency - domain interleaving is an optional step.

[0440] Method 2: After performing periodic extension on the fourth symbol sequence in the time domain, then convert it to the frequency domain for RE mapping to obtain the second symbol sequence.

[0441] According to the properties of the Fourier transform, frequency - domain interleaving is equivalent to time - domain periodic extension. That is, the above - mentioned (N + M) × S time - domain samples are continuously repeated in the time domain. Starting from the starting position, every (N + M) × S time - domain samples can be regarded as a period. And the sub - carrier offset Zp From the perspective of the time domain, it can also be referred to as the number of times the (N + M) × S time-domain samples repeat. Those skilled in the art can understand that continuously repeating the above (N + M) × S time-domain samples in the time domain can achieve phase continuity.

[0442] Therefore, frequency-domain interleaving can also be achieved by means of time-domain periodic extension. Extend the (N + M) × S time-domain samples (Z p −1) times in the time domain, that is, the effect of the aforementioned frequency-domain interleaving can be achieved. Here, the number of times of repeated extension refers to the number of times the (N + M) × S time-domain samples repeat again except for the original (N + M) × S time-domain samples. In other words, if the repeated extension is (Z p −1) times, there are a total of (N + M) × S × Z p time-domain samples, or rather, the number of times the time-domain samples repeat is Z p times. Convert the (N + M) × S × Z p time-domain samples to the frequency domain, and (N + M) × S × Z p frequency-domain samples can be obtained. Then, perform RE mapping on the (N + M) × S × Z p frequency-domain samples, and the (N + M) × S × Z p frequency-domain samples can be mapped to (N + M) × S × Z p REs, and thus the values mapped to each RE can be obtained. Therefore, another possible form of the second symbol sequence is (N + M) × S × Z p frequency-domain samples.

[0443] It can be understood that when Z p = 1, the (N + M) × S time-domain samples do not need to be repeatedly extended in the time domain, or rather, the number of times of repeated extension is 0. According to the properties of the Fourier transform, no periodic extension is required in the time domain, and no zero-padding is required in the frequency domain, that is, no interleaving mapping is required, or rather, mapping is performed in the frequency domain but no interleaving is performed.

[0444] Since the second symbol sequence is used to generate the first OFDM baseband signal, the aforementioned (N + M) × S subcarriers are the frequency-domain resources used to transmit the first OFDM baseband signal.

[0445] Figure 11 (a) and (b) in respectively show two ways of mapping the symbols in the fourth symbol sequence to the REs to obtain the second symbol sequence. Figure 11 In (a) of, the terminal device converts the fourth symbol sequence to the frequency domain through the Fourier transform, performs frequency-domain interleaving and RE mapping, and obtains the values mapped to each RE, that is, the second symbol sequence. Figure 11In (b) thereof, the terminal device obtains Z by performing time-domain periodic extension on the fourth symbol sequence. p The terminal device obtains Z p fourth symbol sequences, and then converts these Z p fourth symbol sequences to the frequency domain, performs RE mapping, and obtains the second symbol sequence. For more detailed content, please refer to the above, and details will not be elaborated here.

[0446] Since when the terminal device processes the data to be transmitted, the resources allocated for different amounts of transmitted data may be different, the number of times of repeated extension of time-domain samples in different transmissions may also be different, and there may even be a situation where no repeated extension is required, such as the case where Z p is 1. The step of time-domain periodic extension can be skipped and not executed. Or, for the convenience of processing, the terminal device can, based on different numbers of repeated extensions, assign different values to Z p . Therefore, regardless of whether repeated extension of time-domain samples is required, the terminal device can execute the step of time-domain periodic extension, but only the value of Z p may be different.

[0447] Among them, Z p can be predefined by the protocol, or configured by the network device, or determined by the terminal device. This application does not make any limitations in this regard.

[0448] If Z p is configured by the network device, optionally, the method further includes: the terminal device receives the first information from the network device, or in other words, the network device sends the first information to the terminal device, and the first information is used to indicate Z p . The network device can indicate Z p to the terminal device through the first information, so as to facilitate the terminal device to perform time-domain periodic extension accordingly, and transmit the first OFDM baseband signal through the corresponding resources. When the network device receives the first OFDM baseband signal from the terminal device, it can also obtain the first OFDM baseband signal accordingly.

[0449] If Z p is determined by the terminal device, optionally, the method further includes: the terminal device sends the first information to the network device, or in other words, the network device receives the first information from the terminal device, and the first information is used to indicate Z p . The terminal device can also determine Z p by itself. For example, the terminal device can determine Z p according to the frequency band bandwidth allocated by the network device to the terminal device, the number of symbols N to be transmitted, the number of extended symbols M, the sampling rate S, etc., and then indicate it to the network device through the first information, so as to facilitate the network device to perform demapping of the first OFDM baseband signal using the same parameters.

[0450] In step 603, the terminal device generates a first OFDM baseband signal based on the second symbol sequence.

[0451] The terminal device may generate a first OFDM baseband signal based on the value on each RE obtained after RE mapping.

[0452] Exemplarily, the first OFDM baseband signal satisfies:

[0453]

[0454] In the formula, satisfies:

[0455]

[0456] Where, represents the value mapped to RE(k, l) for antenna port p and subcarrier spacing configuration μ. In this embodiment, it may refer to the values obtained by mapping (N + M) × S frequency-domain samples to (N + M) × S subcarriers as described above; RE(k, l) represents the RE with frequency-domain index k and time-domain index l; the frequency-domain index k may refer to the index of the subcarrier as k, and this subcarrier index is the index relative to the frequency-domain reference point; the time-domain index l may refer to the index of the OFDM symbol as l, and this OFDM symbol index is the index relative to the time-domain reference point; represents the offset of the starting position of the OFDM symbol corresponding to the first OFDM baseband signal relative to the time-domain reference point. Both the frequency-domain reference point and the time-domain reference point can be predefined. Δf represents the subcarrier spacing, μ represents the subcarrier spacing configuration, and the relationship between μ and Δf is: Δf = 2 μ ·15 [kHz]; μ 0 represents the maximum value of μ in the subcarrier spacing configuration configured by high-layer parameters. represents the size of the resource grid, and the size of this resource grid can be represented by the number of RBs it contains; represents the starting position of the resource grid; represents the number of subcarriers in each RB; represents the preconfigured CP length, for example, the CP length configured by the 5G basic parameter set (numerology). T c represents the basic time unit (basic time unit) in NR. In one possible implementation in this embodiment, T c satisfies: Where κ is a constant, for example, κ is the ratio of the basic time unit T in LTE s to the basic time unit T in NR c which is 64.

[0457] The first OFDM baseband signal may include two parts: a signal body and a first CP. In this embodiment, the signal body may be generated from a second symbol sequence, and the first CP may be obtained by copying a part (such as K 1 symbols) at the end of the signal body to before the signal body. Since the second symbol sequence in this embodiment is obtained by mapping (N + M) modulated symbols in a fourth symbol sequence to REs, it can also be said that the first OFDM baseband signal is generated based on the fourth symbol sequence.

[0458] It should be understood that the generation of the OFDM baseband signal may refer to various existing methods, such as referring to 4G standards, 5G standards, or future 6G standards, etc. This application does not limit this. The above is only an example given in combination with the relevant chapters on OFDM baseband signal generation in 3GPP TS 38.211. For more detailed content, refer to the standards, which will not be elaborated here.

[0459] In this embodiment, the length K of the first CP 1 may be configured by the network device; or, it may also be determined by the terminal device.

[0460] The terminal device may use the resources corresponding to the bandwidth of the frequency band allocated by the network device to transmit the first OFDM baseband signal, that is, the bandwidth of the target frequency band is equal to the bandwidth of the frequency band allocated by the network device. At this time, the length of the first CP is corresponding to the bandwidth of the frequency band allocated by the network device, and the length of the first CP may be configured by the network device.

[0461] Optionally, the method further includes: the terminal device receives third information from the network device, or in other words, the network device sends third information to the terminal device, and the third information is used to indicate the length of the first CP.

[0462] Exemplarily, the third information may directly indicate the value of K 1 , for example, the third information may include the value of K 1 , or other information that can be used to identify the value of K 1 . Or, the third information may also indicate the bandwidth of the frequency band allocated to the terminal device. Since the ratio of the system bandwidth to the bandwidth of the frequency band allocated to the terminal device is equal to the ratio of the CP length corresponding to the system bandwidth to the CP length corresponding to the bandwidth of the frequency band allocated to the terminal device, or in other words, the ratio of the bandwidth of the frequency band allocated to the terminal device to its corresponding CP length is equal to the ratio of the system bandwidth to its corresponding CP length. The terminal device may calculate the length of the first CP according to the bandwidth of the frequency band allocated to the terminal device indicated in the third information, as well as the system bandwidth and its corresponding CP length.

[0463] It should be noted that the system bandwidth and the CP length corresponding to the system bandwidth can be indicated by existing signaling. For example, in 5G, it can be indicated by the index of the basic parameter set (numerology). The system bandwidth and its corresponding CP length can also be indicated by the third information. In this case, in addition to indicating the bandwidth of the frequency band allocated to the terminal device, the third information can also indicate the system bandwidth and the CP length corresponding to the system bandwidth, or indicate other bandwidths different from the system bandwidth and their corresponding CP lengths. It should be understood that regardless of whether the third information indicates the system bandwidth and its corresponding CP length, other bandwidths and their corresponding CP lengths are scaled proportionally according to the system bandwidth and its corresponding CP length, and can all be used to determine the length of the first CP in this application.

[0464] The terminal device can also use part of the resources in the frequency band allocated by the network device to transmit the first OFDM baseband signal, that is, the bandwidth of the target frequency band is less than the bandwidth of the frequency band allocated by the network device. In this case, the length of the first CP corresponds to the bandwidth of the target frequency band. The ratio of the system bandwidth to the bandwidth of the target frequency band is equal to the ratio of the CP length corresponding to the system bandwidth to the length of the first CP, or rather, the ratio of the target frequency band to the length of the first CP is equal to the ratio of the system bandwidth to its corresponding CP length. The terminal device can determine the length of the first CP according to the ratio of the system bandwidth to its corresponding CP length and the bandwidth of the target frequency band, and can notify the network device of the length of the first CP. Among them, the system bandwidth and its corresponding CP length can be configured by the network device, for example, indicated by the index of the basic parameter set (numerology) in 5G.

[0465] Optionally, the method further includes: the terminal device sends the third information to the network device, or rather, the network device receives the third information from the terminal device, and the third information is used to indicate the length of the first CP.

[0466] Exemplarily, the third information can directly indicate the value of K 1 For example, the third information can include the value of K 1 or other information that can be used to identify the value of K 1 Or, the third information can also indicate the bandwidth of the target frequency band. For example, the third information can include the bandwidth value of the target frequency band, or the third information can include the information of the start position and end position of the target frequency band, etc. The start position and end position of the target frequency band can be absolute positions or relative positions relative to a preset reference point. This application does not make any limitations in this regard.

[0467] The time-domain resource of the first OFDM baseband signal can be an OFDM symbol, that is, the first OFDM baseband signal can be mapped to an OFDM symbol in the time domain. In other words, the above fourth symbol sequence can all be transmitted through an OFDM symbol. That is to say, the (N + M) × S time-domain samples used to carry the fourth symbol sequence can be transmitted through an OFDM symbol, and the transmission duration of each time-domain sample is: 1 / [(N + M) × S × Δf], where Δf is the subcarrier spacing, and 1 / Δf is the duration of an OFDM symbol.

[0468] Optionally, the subcarrier spacing is predefined by the protocol or configured by the network device.

[0469] If the subcarrier spacing is configured by the network device, optionally, the method further includes: the terminal device receives seventh information from the network device, or in other words, the network device sends seventh information to the terminal device, and the seventh information is used to indicate the subcarrier spacing. By configuring the subcarrier spacing, the network device can implicitly indicate the duration of an OFDM symbol to the terminal device.

[0470] It should be noted that the subcarrier spacing can also be indicated by existing signaling. For example, in 5G, it can be indicated by the numerology index. In other words, the system bandwidth, the CP length corresponding to the system bandwidth, and the subcarrier spacing can be indicated by the numerology index.

[0471] Based on the foregoing steps 601 to 603, the terminal device can generate and output the first OFDM baseband signal for subsequent operations.

[0472] In a possible implementation, steps 601 to 603 are implemented by a baseband chip in the terminal device.

[0473] Combined with the processes of the foregoing steps 601 to 603, it can be seen that this application constructs a modulation symbol sequence with self-looping phase at the beginning and end, which can ensure the phase continuity and constant envelope between the CP sequence and the modulation symbol sequence, and achieve a PAPR of 0 dB. Then, the single-carrier modulation symbol sequence is shifted and embedded into the given frequency-domain resource, and then the CP that meets the length constraint is added to ensure compatibility with the OFDM technology and achieve interference-free coexistence.

[0474] It should be noted that the foregoing RE mapping is used to determine to which subcarriers the samples obtained by converting the (N+M) modulation symbols in the fourth symbol sequence into the frequency domain are mapped, without considering the frequency-domain resources of the first CP. This is because the subcarriers to which the RE mapping is performed are also the subcarriers used to transmit the first OFDM baseband signal. After the first OFDM baseband signal is generated, the terminal device can directly use these subcarriers to transmit the first CP. The first CP only occupies different resources from the signal body in the time domain, that is, the first CP is located before the signal body, and this can be achieved through the generation formula of the OFDM baseband signal (such as formula 3 above). Therefore, in this embodiment, the object of the RE mapping is the samples corresponding to the (N+M) modulation symbols in the frequency domain, and neither includes the first CP, nor the symbols used to generate the first CP (such as the K 1 modulation symbols at the end of the (N+M) modulation symbols, which can be abbreviated as the first CP sequence) or the samples corresponding to them in the frequency domain. In other words, there is no need to perform RE mapping on the first CP, the first CP sequence, and the samples corresponding to them in the frequency domain. That is to say, neither the foregoing fourth symbol sequence nor the second symbol sequence includes the first CP or the first CP sequence. Therefore, even if a modulation method that can ensure phase continuity is used, such as CPM or LFM, etc., if the first symbol sequence is not extended and modulation is directly performed based on the first symbol sequence, a phase-continuous first OFDM baseband signal cannot be obtained.

[0475] In step 604, the terminal device outputs a bandpass signal based on the first OFDM baseband signal.

[0476] The terminal device (such as specifically the radio frequency chip in the terminal device) can shift the first OFDM baseband signal to the target frequency band to facilitate transmission. Exemplarily, the target frequency band may refer to a part of the frequency band allocated by the network device for the terminal device to use. For example, the terminal device determines a part of the frequency band from the frequency band allocated by the network device for data transmission; or, the target frequency band may be the entire frequency band allocated by the network device for the terminal device to use. This application does not make any limitations in this regard.

[0477] In step 603, the terminal device has mapped the (N+M) modulation symbols in the fourth symbol sequence to the frequency-domain resources in the baseband through RE mapping, that is, determined the relative position of the frequency-domain resources of the first OFDM baseband signal. After determining the position of the target frequency band, the terminal device can determine the absolute position of the frequency-domain resources of the first OFDM baseband signal according to the center frequency of the target frequency band, and then perform upconversion.

[0478] Optionally, before step 604, the method further includes: the terminal device determines the absolute position of the frequency-domain resources of the first OFDM baseband signal.

[0479] Since the frequency-domain resources of the first OFDM baseband signal include (N + M) × S subcarriers, and these (N + M) × S subcarriers may be continuous or discontinuous, the central position of this frequency-domain resource is found and aligned with the central frequency of the target frequency band, thereby determining the absolute position of the frequency-domain resource for transmitting the first OFDM baseband signal.

[0480] Exemplarily, if the (N + M) × S subcarriers are continuous and (N + M) × S is odd, the central position of the (N + M) × S subcarriers is the central frequency point of the subcarrier with the middle number (i.e., the median number), that is, starting from 1, it is the central frequency point of the ((N + M) × S + 1) / 2-th subcarrier among the (N + M) × S subcarriers. If the (N + M) × S subcarriers are continuous and (N + M) × S is even, the central position of the (N + M) × S subcarriers is the average value of the frequency points of two adjacent subcarriers with the middle numbers, that is, starting from 1, it is the average value of the frequency points of the (N + M) × S / 2-th subcarrier and the ((N + M) × S / 2 + 1)-th subcarrier among the (N + M) × S subcarriers. If the (N + M) × S subcarriers are discontinuous, the total number of subcarriers included between the first subcarrier and the last subcarrier among the (N + M) × S subcarriers can be determined first, and then the central position can be determined according to the total number of subcarriers. Specifically, it can be processed according to the cases where the total number of subcarriers is odd and even respectively as described above. The specific processing method can refer to the above text and will not be elaborated here.

[0481] Among them, the position of the target frequency band can be determined according to the position of the frequency band allocated by the network device to the terminal device. For example, the target frequency band can be the frequency band allocated by the network device to the terminal device, and in this case, their positions are the same; the target frequency band can also be a partial bandwidth within the frequency band allocated by the network device to the terminal device. In this case, the position of the target frequency band is within the position of the frequency band allocated by the network device to the terminal device. Specifically, it can be determined by the terminal device itself or indicated by the network device. This application does not make any limitations in this regard.

[0482] The position of the frequency band allocated by the network device to the terminal device can be indicated by the network device through signaling. Optionally, the method further includes: the network device sends the eighth information to the terminal device, or in other words, the terminal device receives the eighth information from the network device, and the eighth information is used to indicate the position of the frequency band allocated by the network device to the terminal device.

[0483] After determining the absolute position of the frequency-domain resource, the terminal device can execute step 604 to shift the first OFDM baseband signal to the target frequency band.

[0484] A possible implementation of step 604 is that the terminal device directly frequency-modulates the carrier based on the first OFDM baseband signal to obtain a bandpass signal.

[0485] In the embodiments of the present application, since the first OFDM baseband signal is generated based on the second symbol sequence, and the second symbol sequence is obtained by mapping (N + M) modulated symbols obtained by phase or frequency modulation methods such as CPM or LFM to the REs. Phase or frequency modulation aims to modulate the information to be transmitted on the phase or frequency, rather than carrying information through the amplitude. Therefore, the conversion from the baseband signal to the bandpass signal can be achieved by direct frequency modulation, that is, upconversion is realized. Since the signal obtained by direct frequency modulation can be called a frequency-modulated signal, the bandpass signal obtained by upconversion through direct frequency modulation is a frequency-modulated signal.

[0486] To perform upconversion by direct frequency modulation, for example, devices such as PLL, VCO, and DCO that can generate sinusoidal waves with adjustable frequencies can be used. Compared with Figure 3 the transmitter architecture shown, the frequency band shift of the signal realized by the mixer in I / Q modulation can be avoided, power consumption can be saved, and the circuit structure is also more simplified, which can reduce costs.

[0487] Of course, the implementation method of upconversion is not limited to direct frequency modulation. In another possible implementation, the terminal device uses I / Q modulation technology to perform upconversion on the first OFDM baseband signal to obtain a bandpass signal.

[0488] Exemplarily, if I / Q modulation technology is desired, the first OFDM baseband signal generated by the terminal device can be an I-channel baseband signal and a Q-channel baseband signal. That is, the first OFDM baseband signal generated by the terminal device in step 603 is not limited to the form calculated by formula 3. The terminal device can directly generate the I-channel baseband signal and the Q-channel baseband signal based on the second symbol sequence in step 603, or can obtain the I-channel baseband signal and the Q-channel baseband signal through mathematical transformation (for example, taking the real part and the imaginary part of the baseband signal in formula 3 respectively) after calculating based on the second symbol sequence by formula 3. The present application does not make any limitations in this regard.

[0489] Correspondingly, in step 604, after the I-channel baseband signal and the Q-channel baseband signal are output from the baseband chip to the upconversion module, they can be mixed by the I-channel mixer and the Q-channel mixer respectively to realize frequency band shift, and a bandpass signal is obtained after superposition. In this case, the terminal device can, for example, use one of PLL, VCO, or DCO, and a mixer to realize upconversion. Compared with direct frequency modulation, more devices are introduced, the circuit complexity is higher, and the transmission power consumption and cost are also higher.

[0490] In step 605, the terminal device amplifies the power of the band-pass signal to obtain the power-amplified band-pass signal.

[0491] As described above, power amplification may include linear power amplification or non-linear power amplification. Combining with the Figure 4 three different transmitter structures shown above, it can be known that in this application, the power amplification of the band-pass signal can adopt the method of linear power amplification or the method of non-linear power amplification.

[0492] For example, in step 604, direct frequency modulation is adopted, and in step 605, linear power amplification or non-linear power amplification is adopted. Another example is that in step 604, I / Q modulation is adopted, and in step 605, non-linear power amplification is adopted. The above several examples can all reduce the transmission power from at least one of the two dimensions of up-conversion and power amplification.

[0493] In a possible implementation manner, steps 604 and 605 can be implemented by a radio frequency chip in the terminal device.

[0494] In step 606, the terminal device sends the power-amplified band-pass signal. Correspondingly, the network device receives the power-amplified band-pass signal.

[0495] The terminal device can send the power-amplified band-pass signal through a transmitting antenna. The network device can receive the band-pass signal from the terminal device through a receiving antenna. It can be understood that the band-pass signal received by the network device is the band-pass signal sent by the terminal device after power amplification.

[0496] It should be understood that each step shown in steps 601 to 606 above is only an example, and should not constitute any limitation on the operations performed by the terminal device. The terminal device may also perform other operations other than the foregoing content. For example, before obtaining the first symbol sequence, channel coding and modulation are performed; another example is that digital-to-analog conversion is performed before outputting the first OFDM baseband signal; and another example is that filtering and gain adjustment are performed before outputting the first OFDM baseband signal, etc. This application does not make any limitations in this regard.

[0497] It should also be understood that during the transmission process of the signal from the terminal device to the network device, the signal may be distorted due to external interference or the quality of the wireless channel not being ideal, etc., and there may be a certain error rate. Therefore, the first symbol sequence, the second symbol sequence, the third symbol sequence, the extended symbol, etc. described in this article may be different symbol sequences in the terminal device and the network device. In the article, the symbol sequences in different processing stages are defined with the same name only for the convenience of understanding and explanation.

[0498] To better understand the method provided in this application, the following will be combined with Figure 4Several different transmitter structures shown are used to illustrate the processing procedure of the terminal device from obtaining the first symbol sequence to transmitting the band - pass signal. As shown in (a) of Figure 12A , after the terminal device obtains the first symbol sequence to be transmitted, it first expands the first symbol sequence to determine the third symbol sequence, and then modulates the third symbol sequence to obtain the fourth symbol sequence. As mentioned before, the fourth symbol sequence obtained by modulating the third symbol sequence is a continuous symbol sequence, and after sampling, multiple discrete time - domain samples can be obtained. For the sake of simplicity, the continuous fourth symbol sequence and the discrete fourth symbol sequence are not distinguished in the following text and figures. It can be understood that whether it is the continuous fourth symbol sequence or the discrete fourth symbol sequence, they can all be collectively referred to as the fourth symbol sequence. The terminal device can perform a Fourier transform on the fourth symbol sequence, convert the fourth symbol sequence to the frequency domain and then perform RE mapping to obtain the second symbol sequence. The terminal device can generate the first OFDM base - band signal based on the second symbol sequence. After obtaining the first OFDM base - band signal through the above base - band processing, the terminal device can directly frequency - modulate the carrier based on the first OFDM base - band signal, output the band - pass signal, and then perform power amplification on the band - pass signal, and send the power - amplified band - pass signal through the transmitting antenna. Among them, power amplification includes non - linear power amplification or linear power amplification.

[0499] Figure 12A The processing shown in (b) of Figure 12A is similar to that in (a) of Figure 12A , the difference lies in the way of obtaining the fourth symbol sequence. After the terminal device obtains the first symbol sequence to be transmitted, it first expands the first symbol sequence to determine the third symbol sequence, and then modulates and samples N symbols to be transmitted and M extended symbols in the third symbol sequence respectively to obtain N modulated symbols and M modulated symbols, and splicing the N modulated symbols and M modulated symbols can obtain the fourth symbol sequence. The subsequent operations are the same as those in (a) of

[0500] Figure 12A , and will not be elaborated here.

[0500] Figure 12A The operations of Fourier transform and RE mapping shown in (a) and (b) of Figure 11 correspond to those in (a) of Figure 12A . It can be understood that the operations of Fourier transform and RE mapping shown in (a) and (b) of Figure 12A can also be replaced by those in (b) of Figure 11 , that is, after performing time - domain periodic extension on the fourth symbol sequence, then performing Fourier transform to convert it to the frequency domain, and then performing RE mapping. As shown in (a) and (b) of Figure 12B , the specific operations in the figure can be referred to the previous description and will not be elaborated here.

[0501] Figure 12A (a) and (b) ofFigure 12B In (a) and (b) of , the extension may correspond to step 6021 above, modulation, sampling, and stitching may correspond to step 6022 above, Fourier transform, frequency-domain interleaving, and RE mapping may correspond to Method 1 in step 6023 above, time-domain periodic extension, Fourier transform, and RE mapping may correspond to Method 2 in step 6023 above, OFDM baseband signal generation may correspond to step 603 above, direct frequency modulation may correspond to step 604 above, and non-linear / linear power amplification may correspond to step 605 above. The operations in the figure can be referred to the relevant descriptions of the corresponding steps above and will not be elaborated here.

[0502] It should be understood that Figure 12A In (a), (b) of Figure 12B The processing procedures shown in (a), (b) of can be applied to Figure 4 In (a) and (c) of . Figure 4 The difference between (a) and (c) of lies in the power amplifier. In Figure 4 In (a) of , the power amplifier is a non-linear power amplifier. Therefore, Figure 12A and Figure 12B In the processing procedures shown in (a) and (b) of and , the linear / non-linear power amplification can specifically be non-linear power amplification; in Figure 4 In (c) of , the power amplifier is a linear power amplifier. Therefore, Figure 12A and Figure 12B In the processing procedures shown in (a) and (b) of and , the linear / non-linear power amplification can specifically be linear power amplification.

[0503] Figure 13A In (a), (b) of Figure 13B The processing procedures shown in (a), (b) of can be applied to Figure 4 In (b) of , Figure 4 The difference between (b) and (a) of lies in the devices used for up-conversion, and the corresponding Figure 13A In (a), (b) of Figure 13B The specific processing methods of up-conversion shown in (a), (b) of are also different from Figure 12A In (a), (b) of Figure 12B The specific processing methods of up-conversion shown in (a), (b) of . Figure 12A In (a), (b) of Figure 12B The specific processing method of up-conversion shown in (a), (b) of is direct frequency modulation, the input is the first OFDM baseband signal, and the output is a band-pass signal (or a frequency-modulated signal). Figure 13A In (a), (b) of Figure 13BThe specific up-conversion processing method shown in (a) and (b) therein is I / Q modulation. The inputs are the I-channel baseband signal and the Q-channel baseband signal, and the output is a band-pass signal. Among them, the I-channel baseband signal and the Q-channel baseband signal are obtained based on the first OFDM baseband signal. The specific generation method has been described above and will not be elaborated here. Other operations are the same as Figure 12A in (a) and (b) therein and Figure 12B in (a) and (b) therein, which will not be elaborated here.

[0504] In step 607, the network device obtains the first OFDM baseband signal based on the band-pass signal.

[0505] The network device (specifically, the radio frequency chip in the network device) can perform down-conversion on the received band-pass signal to obtain the first OFDM baseband signal. The process of the network device performing down-conversion on the received band-pass signal can be implemented by existing down-conversion technologies, and this application does not limit this.

[0506] Exemplarily, in a RAN deployed with CU, DU, and RU, the specific implementation of steps 606 and 607 can be: The RU receives the band-pass signal and forwards the received band-pass signal to the DU for processing to obtain the first OFDM baseband signal; in ORAN, the specific implementation of steps 606 and 607 can be: The O-RU receives the band-pass signal and forwards the band-pass signal to the O-DU for processing after partial physical layer processing to obtain the first OFDM baseband signal.

[0507] After the radio frequency chip of the network device obtains the first OFDM baseband signal through down-conversion, it can output the first OFDM baseband signal to the baseband chip of the network device for further processing by the baseband chip. Optionally, the network device can also perform noise suppression on the received band-pass signal before down-conversion. For example, the network device can use a low noise amplifier (LNA) to perform noise suppression to output a signal with a high signal-to-noise ratio (SNR). Since the specific process of using an LNA to perform noise suppression can refer to the existing technology, it will not be elaborated here.

[0508] In step 608, the network device obtains the fourth symbol sequence based on the first OFDM baseband signal.

[0509] The network device (specifically, the baseband chip in the network device) can sample the first OFDM baseband signal from the radio frequency chip to obtain a discrete signal. In this embodiment, ((N + M) × S × Z p + K 1(N + M) × S) time-domain samples. Since the CP of the first OFDM baseband signal (i.e., the first CP) is K symbols at the end of the signal body of the first OFDM baseband signal, the ((N + M) × S × Z 1 + K p × S) time-domain samples obtained by sampling include two parts corresponding to the signal body and the first CP respectively, that is, Z 1 fourth symbol sequences and the first CP sequence. The network device can obtain the fourth symbol sequence from the first OFDM baseband signal, where S is the sampling rate, and Z p is the subcarrier offset between two adjacent teeth in the frequency domain, or the number of times the time-domain samples repeat. p Exemplarily, in a RAN deployed with CU, DU, and RU, the specific implementation of step 608 can be: the DU obtains the fourth symbol sequence based on the first OFDM baseband signal; in ORAN, the specific implementation of step 608 can be: the O-DU obtains the fourth symbol sequence based on the first OFDM baseband signal.

[0510] Optionally, step 608 specifically includes:

[0511] Step 6081, the network device obtains Z

[0512] fourth symbol sequences based on the first OFDM baseband signal; p The network device (specifically, the baseband chip in the network device) can sample the first OFDM baseband signal from the radio frequency chip to obtain a discrete signal. In this embodiment, ((N + M) × S × Z

[0513] + K p × S) time-domain samples can be obtained. Since the CP of the first OFDM baseband signal (i.e., the first CP) is K symbols at the end of the signal body of the first OFDM baseband signal, the ((N + M) × S × Z 1 + K 1 × S) time-domain samples obtained by sampling include two parts corresponding to the signal body and the first CP respectively, that is, Z p + K 1 × S) time-domain samples include two parts corresponding to the signal body and the first CP respectively, that is, Z p fourth symbol sequences and the first CP sequence.

[0514] Step 6082, the network device obtains the fourth symbol sequence from the Z p fourth symbol sequences.

[0515] Exemplarily, the network device can remove the first CP sequence according to the length of the first CP to obtain Z pA fourth symbol sequence, and then through RE demapping, the fourth symbol sequence is obtained. The obtained fourth symbol sequence includes L modulation symbols, L = M + N, that is, the L modulation symbols include (M + N) modulation symbols obtained by modulating the third symbol sequence composed of N symbols to be transmitted and M extended symbols.

[0516] As described above, the length of the first CP can be configured by the network device or determined by the terminal device and indicated to the network device. Therefore, the network device can pre-determine the length of the first CP, and then obtain the second symbol sequence according to the length of the first CP.

[0517] Corresponding to the implementation method of the terminal device in step 6023 above, in step 6082, the network device can obtain the fourth symbol sequence by converting Z p fourth symbol sequences to the frequency domain to perform demapping and frequency-domain deinterleaving, or directly perform non-periodic or periodic merging in the time domain to obtain the fourth symbol sequence.

[0518] The following will describe step 6082 in detail in combination with two different methods.

[0519] Method 1: Perform non-periodic or periodic merging on Z p fourth symbol sequences in the time domain to obtain the fourth symbol sequence.

[0520] In this embodiment, Z p can be 1 or greater than 1. Z p being 1 means that in the previous step 6023, the terminal device did not perform time-domain periodic extension on the fourth symbol sequence, or did not perform interleaving on (N + M) × S frequency-domain samples in the frequency domain. Z p being greater than 1 means that in the previous step 6023, the terminal device performed at least one repeated extension on the fourth symbol sequence, or performed interleaving on (N + M) × S frequency-domain samples in the frequency domain.

[0521] Correspondingly, when Z p is greater than 1, the network device can perform non-periodic or periodic merging in the time domain on Z p fourth symbol sequences to obtain the fourth symbol sequence.

[0522] Among them, non-periodic in the time domain specifically means removing (Z p - 1) periods from Z p periods, or in other words, retaining one complete period in Z p periods to obtain the fourth symbol sequence. Among them, the retained one period can be Z pOne of the cycles, and which cycle to retain specifically is not limited in this application. The time-domain cycle merging specifically means that the corresponding time-domain samples in Z p cycles are merged by means such as taking the average value or taking the weighted average value to obtain a complete cycle as the fourth symbol sequence. Among them, the corresponding time-domain samples in Z p cycles can be understood as follows: If the (N + M) × S samples in each of the Z p cycles are numbered respectively, the samples with the same number in the Z p cycles are the corresponding time-domain samples in the Z p cycles. It can be understood that cycle merging merges the time-domain samples in multiple cycles, so it has a higher gain compared to cycle removal.

[0523] In the case where Z p is equal to 1, the fourth symbol sequence can be obtained after removing the first CP sequence, and time-domain cycle removal or cycle merging can be skipped without execution.

[0524] Also, since the network device processes the OFDM baseband signal, the number of times of repeated extension of the time-domain samples in the OFDM baseband signals obtained in different times may be different, that is, the value of Z p may be different. The network device may need to perform time-domain cycle removal or cycle merging, or may not need to perform time-domain cycle removal or cycle merging. As mentioned above, Z p can be configured by the network device or determined by the terminal device. Therefore, the network device can obtain this Z p in advance and then determine whether to perform time-domain cycle removal or cycle merging.

[0525] It can be understood that in the case where Z p is greater than 1, the network device can obtain the fourth symbol sequence by executing steps 6081 and 6082; in the case where Z p is equal to 1, the network device can directly obtain the fourth symbol sequence through step 6081, and step 6082 can be skipped without execution.

[0526] Method 2: Convert the Z p fourth symbol sequences to the frequency domain, after de-RE mapping and frequency-domain de-interleaving, and then convert them back to the time domain to obtain the fourth symbol sequence.

[0527] Due to the characteristics of the Fourier transform, time-domain periodic extension and frequency-domain interleaving are equivalent. Correspondingly, time-domain cycle removal or time-domain cycle merging and frequency-domain de-interleaving are also corresponding. Therefore, in the case where Z p is greater than 1, when the network device obtains Z pAfter a fourth symbol sequence, it can also be transformed into the frequency domain. After performing demapping of RE and frequency-domain deinterleaving in the frequency domain, it is then transformed back into the time domain to obtain the fourth symbol sequence. In the case where Z p is equal to 1, frequency-domain deinterleaving can also be skipped without execution.

[0528] It can be understood that in the case where Z p is greater than 1, the network device can obtain the fourth symbol sequence by performing steps 6081 and 6082; in the case where Z p is equal to 1, the network device can obtain the fourth symbol sequence through step 6081. The network device can perform demapping of RE when executing 6082 without performing frequency-domain deinterleaving.

[0529] In step 609, the network device demodulates based on the fourth symbol sequence to obtain the third symbol sequence.

[0530] Exemplarily, in a RAN deployed with CU, DU, and RU, the specific implementation of step 609 can be: the DU demodulates based on the fourth symbol sequence to obtain the third symbol sequence; in ORAN, the specific implementation of step 609 can be: the O-DU demodulates based on the fourth symbol sequence to obtain the third symbol sequence.

[0531] As already described in step 6022, the fourth symbol sequence is modulated by the terminal device based on the third symbol sequence. Therefore, the network device can use a corresponding demodulation method to demodulate the fourth symbol sequence to obtain the third symbol sequence.

[0532] Exemplarily, corresponding to the modulation method of the terminal device, the demodulation methods of the network device for the fourth symbol sequence include: CPM demodulation or LFM demodulation. The specific method for the network device to demodulate the fourth symbol sequence can be determined by the network device itself. The network device can use the method of CPM demodulation or LFM demodulation for demodulation, or can also use other methods for demodulation. For example, those skilled in the art can make simple transformations based on the same concept on the basis of CPM demodulation or LFM demodulation to achieve the same effect. For example, taking CPM demodulation as an example, converting the demodulation in the phase domain to other domains and then converting back to the phase domain after demodulation, its essence is still to complete CPM demodulation, or rather, it is essentially the same as CPM demodulation, and so on, which will not be elaborated here.

[0533] Optionally, before step 609, the method further includes: the network device performs channel equalization.

[0534] Channel equalization is based on the channel obtained from channel estimation. By using an equalization algorithm, the influence of the channel is removed to ensure the correct demodulation of the signal. Channel equalization can include channel equalization in the frequency domain (which can be abbreviated as frequency-domain equalization) or channel equalization in the time domain (which can be abbreviated as time-domain equalization). In other words, the network device can perform channel equalization in the frequency domain, that is, use a frequency-domain equalization algorithm to remove the influence of the channel, or perform channel equalization in the time domain, that is, use a time-domain equalization algorithm to remove the influence of the channel.

[0535] For example, when the network device executes step 6082 and obtains the fourth symbol sequence through time-domain de-periodization or time-domain periodic merging, it can directly adopt a time-domain equalization algorithm for channel equalization, thereby avoiding the computational complexity brought by the time-frequency domain conversion and saving power consumption. Of course, the network device can also convert the signal to the frequency domain, adopt a frequency-domain equalization algorithm, perform channel equalization in the frequency domain, and then convert back to the time domain.

[0536] For another example, when the network device executes step 6082 and obtains the fourth symbol sequence through frequency-domain de-interleaving, the network device can also perform channel equalization by adopting a frequency-domain equalization algorithm after converting the first OFDM baseband signal to the frequency domain, and then convert back to the time domain after completing the frequency-domain de-interleaving.

[0537] In step 610, the network device obtains the first symbol sequence from the third symbol sequence.

[0538] Exemplarily, in a RAN deployed with CU, DU, and RU, the specific implementation of step 610 can be: the DU obtains the first symbol sequence from the third symbol sequence; in ORAN, the specific implementation of step 610 can be: the O-DU obtains the first symbol sequence from the third symbol sequence.

[0539] As described in step 602 above, the third symbol sequence includes N symbols to be transmitted and M extended symbols. The third symbol sequence obtained by the network device from the second symbol sequence also includes L symbols, and these L symbols include: N symbols corresponding to the N symbols to be transmitted (for easy distinction, denoted as N first symbols) and M extended symbols added to obtain a constant envelope waveform. The network device can obtain the first symbol from the third symbol sequence according to the position of the M extended symbols in the third symbol sequence and the value of M.

[0540] Optionally, step 610 includes:

[0541] Step 6101, the network device determines the value of M;

[0542] Step 6102, the network device determines the position of the M extended symbols in the third symbol sequence;

[0543] Step 6103, the network device obtains the first symbol sequence from the third symbol sequence.

[0544] Among them, the value of M can be predefined by the protocol, or can be configured by the network device, or can be determined by the terminal device. If the value of M is predefined by the protocol or configured by the network device, the network device can know the value of M in advance, and this value of M can be pre-stored in the memory (such as cache) of the network device. When the network device executes step 6101, it can determine the value of M by reading the data in the memory; if the value of M is determined by the terminal device, when the network device executes step 6101, it can parse the value of M from the sixth information received from the terminal device.

[0545] A possible situation is that the value of M is zero, that is, L = N, and the L symbols demodulated by the network device based on the second symbol sequence are all the N first symbols that the terminal device hopes to transmit. When the network device executes step 6103, it can determine the third symbol sequence as the first symbol sequence according to the value of M being zero, without having to execute step 6102. It should be understood that in this case, step 609 and step 6103 can also be regarded as the same step, and step 6101 can be executed before step 609.

[0546] Another possible situation is that the value of M is not zero, that is, M > 0, L > N, and the L symbols demodulated by the network device based on the second symbol sequence include N first symbols and M extended symbols. When the network device executes step 6103, it can remove the M extended symbols from the third symbol sequence according to the value of M and the positions of the M extended symbols in the third symbol sequence to obtain N first symbols, that is, obtain the first symbol sequence.

[0547] Among them, the positions of the M extended symbols in the third symbol sequence can be predefined by the protocol, or can be configured by the network device, or can be determined by the terminal device. If the positions of the M extended symbols in the third symbol sequence are predefined by the protocol or configured by the network device, the network device can predict the positions of the M extended symbols in the third symbol sequence. When the network device executes step 6102, it can determine the positions of the M extended symbols in the third symbol sequence by reading the data in the memory; if the positions of the M extended symbols in the third symbol sequence are determined by the terminal device, when the network device executes step 6102, it can parse the positions of the M extended symbols in the third symbol sequence from the information (such as the fifth information) received from the terminal device.

[0548] For example, assume that M is 1, and the position of the M extended symbols in the third symbol sequence is after the N first symbols. Then the network device can remove the last symbol in the third symbol sequence, and the obtained N symbols are the N first symbols and can form the first symbol sequence.

[0549] The possible cases of the positions of the M extended symbols in the third symbol sequence have been described in detail in the above steps and will not be elaborated here. Regardless of the positions of the M extended symbols in the third symbol sequence, the network device can remove them from the third symbol sequence to obtain the first symbol sequence. For the sake of brevity, no examples will be given here one by one.

[0550] In a possible implementation, steps 608 to 610 are implemented by the baseband chip in the network device.

[0551] To better understand the processing process of the network device for the received signal, the processing process of the network device from receiving the bandpass signal to obtaining the first symbol sequence will be described with reference to the accompanying drawings below.

[0552] Figure 14 The processing processes shown in (a) and (b) in Figure 12A , Figure 12B and Figure 13A , Figure 13B correspond, and can be used to process the bandpass signal transmitted based on the processing process of any one of the accompanying drawings in Figure 12A , Figure 12B Figure 13A or Figure 13B .

[0553] As shown in (a) of Figure 14 , after receiving the bandpass signal, the network device can first perform down-conversion on the received bandpass signal. The bandpass signal is shifted to the baseband after down-conversion to obtain the first OFDM baseband signal. After sampling the first OFDM baseband signal, ((N + M) × S × Z p +K 1 ×S) samples (or time-domain samples) can be obtained, that is, Z p fourth symbol sequences and the first CP sequence. After removing the CP sequence and performing time-domain decimation or period merging, the network device can obtain the fourth symbol sequence. Thereafter, the network device can demodulate the fourth symbol sequence to obtain the third symbol sequence, and then remove the M extended symbols from the third symbol sequence to obtain the first symbol sequence. Optionally, to ensure correct demodulation of the fourth symbol sequence, the network device can perform channel equalization before time-domain decimation. Figure 14 The processing shown in (a) of

[0554] In (a) of 14, downconversion may correspond to step 607 above, sampling and removing the CP sequence may correspond to step 6081 above, time-domain equalization and time-domain de-periodization / period merging may correspond to step 6082 above, demodulation may correspond to step 609 above, and removing the extended symbol may correspond to step 610 above. For the operations in the figure, please refer to the relevant descriptions of the corresponding steps above, and will not be elaborated here.

[0555] Figure 14 In (b) of Figure 14 is similar to the steps in (a) of p except that the operations of obtaining the fourth symbol sequence and channel equalization in step 6082 are converted to be performed in the frequency domain. After removing the CP sequence to obtain Z Figure 14 the fourth symbol sequences, they can be transformed to the frequency domain through Fourier transform, then frequency-domain equalization and frequency-domain de-interleaving are performed, and then transformed back to the time domain through inverse Fourier transform to obtain the fourth symbol sequence. Among them, downconversion may correspond to step 607 above, sampling and removing the CP sequence may correspond to step 6081 above, Fourier transform, demapping, frequency-domain equalization, frequency-domain de-interleaving and inverse Fourier transform may correspond to step 6082 above, demodulation may correspond to step 609 above, and removing the extended symbol may correspond to step 610 above. Figure 14 For other steps in (b) of Figure 14 please refer to the relevant descriptions of (a) of

[0556] Based on the above technical solutions, by expanding the first symbol sequence, the third symbol sequence is obtained, and then based on the third symbol sequence, modulation and RE mapping are performed to obtain the second symbol sequence. The second symbol sequence obtained thereby can simultaneously satisfy: continuous phase, and the phase at the head and tail is self-cycled. The signal body of the first OFDM baseband signal generated based on this second symbol sequence and the CP also satisfy continuous phase. Based on this, if the modulation technology adopted is a modulation technology that can maintain a constant amplitude, a waveform with continuous phase and constant envelope can be obtained. In this way, a scheme of combining phase or frequency modulation technology and OFDM technology to obtain a constant envelope waveform can be realized. Since the constant envelope waveform meets the requirements of the waveform for direct frequency conversion and nonlinear power amplification, the communication device can use some more power-saving ways to transmit signals. Therefore, for communication devices (especially IoT nodes with small volume and without large-capacity batteries), the standby life is improved. In addition, the steps such as RE mapping and OFDM baseband signal generation of the terminal device are consistent with the current standards, and the compatibility is good.

[0557] After receiving the bandpass signal and demodulating to obtain the third symbol sequence, the network device can obtain the first symbol sequence from the third symbol sequence according to the number of extended symbols and in combination with the positions of the extended symbols in the third symbol sequence, so that the first symbol sequence can be received. It can be seen that the processing process of the network device after receiving the bandpass signal does not need to be greatly modified compared with the current processing process, so the compatibility is better.

[0558] As described above in conjunction with Figures 6 to 14 illustrates an embodiment provided by the present application. In this embodiment, the generation of the first OFDM baseband signal is basically the same as the definition in the current 3GPP standard, and the compatibility is better. According to the properties of the Fourier transform, the signal processing process in the frequency domain can also be converted to the time domain. For example, the RE mapping can also be completed by time-domain periodic extension, and the generation of the OFDM baseband signal can also be completed in the time domain. Thus, operations such as Fourier transform and inverse transform can be omitted, thereby reducing the computational complexity and further saving power consumption. Another possible embodiment of the communication method provided by the present application will be described in detail below.

[0559] Figure 15 is a schematic flowchart of a communication method provided by another embodiment of the present application.

[0560] Figure 15 The method 1500 shown may include steps 1501 to 1510. Among them, steps 1501 to 1506 are the processes executed by the terminal device, and steps 1506 to 1510 are the processes executed by the network device. Exemplarily, steps 1501 to 1503 may be executed by the baseband chip of the terminal device, step 1504 may be executed by the up-conversion module of the terminal device, step 1505 may be executed by the power amplifier of the terminal device, and the sending operation in step 1506 may be executed by the antenna (such as the transmitting antenna) of the terminal device. The receiving operation in step 1506 may be executed by the antenna (such as the receiving antenna) of the network device, step 1507 may be executed by the down-conversion module of the network device, and steps 1508 to 1510 may be executed by the baseband chip of the network device.

[0561] The following details each step in method 1500.

[0562] In step 1501, the terminal device obtains a first symbol sequence, and the first symbol sequence includes N symbols to be transmitted.

[0563] For the specific description of step 1501, reference may be made to step 601 in method 600 above. For the sake of brevity, it will not be repeated here.

[0564] In step 1502, the terminal device generates a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence based on the first symbol sequence.

[0565] Different from method 600, before generating the first OFDM baseband signal, the terminal device can pre-generate a first CP sequence corresponding to the first CP, and then generate the first OFDM baseband signal based on the fourth symbol sequence and the first CP sequence.

[0566] In this embodiment, the terminal device can obtain the fourth symbol sequence through modulation. Similar to method 600, the modulation in this application is continuous-phase modulation. Exemplarily, the modulation includes CPM or LFM. If the terminal device directly modulates based on the first symbol sequence, there may be a situation where the phase of the generated OFDM baseband signal jumps, resulting in an unconstant envelope. Therefore, the terminal device can add several (such as M) extended symbols on the basis of the first symbol sequence, and design the extended symbols to achieve self-circulation of the head and tail phases of the second symbol sequence, so as to make the phase of the OFDM baseband signal generated based on the second symbol sequence continuous.

[0567] Wherein, M can be an integer greater than or equal to zero. When M is zero, the third symbol sequence is the same as the first symbol sequence; when M is greater than zero, the third symbol sequence is different from the first symbol sequence. The third symbol sequence is a sequence obtained by adding one or more extended symbols while keeping the order of the N symbols to be transmitted in the first symbol sequence unchanged.

[0568] Optionally, step 1502 includes:

[0569] The terminal device determines a third symbol sequence based on the first symbol sequence; and

[0570] The terminal device generates a fourth symbol sequence and a first CP sequence located before the fourth symbol sequence based on the third symbol sequence.

[0571] For the specific process of the terminal device determining the third symbol sequence based on the first symbol sequence, reference can be made to the relevant description in step 6021 of method 600 above. For the sake of brevity, it will not be elaborated here.

[0572] The process by which the terminal device generates the fourth symbol sequence and the first CP sequence based on the third symbol sequence mainly includes: modulation, CP sequence generation, and RE mapping. Among them, modulation includes modulation based on the third symbol sequence, and the output after modulation includes the fourth symbol sequence; RE mapping is to map each modulated symbol in the fourth symbol sequence to the RE to obtain the value carried on each RE. In this embodiment, RE mapping is achieved through time-domain periodic extension; CP sequence generation is to generate the first CP sequence located before the fourth symbol sequence, and this first CP sequence includes K 1 modulated symbols, corresponding to the K 1 symbols at the end of the third symbol sequence. Among them, modulation and CP sequence generation can be simultaneous or executed separately.

[0573] Among them, for the process of the terminal device modulating the third symbol sequence, reference can be made to the detailed description of combining CPM and LFM in the previous method 600, and the third symbol sequence is used as the input of CPM or LFM to obtain the fourth symbol sequence For the specific implementation, reference can be made to the previous related description, and just replace a with That's all, and no further elaboration will be provided.

[0574] Figure 16 (a), (b), and (c) in

[0575] show three possible implementation manners of step 1502. Figure 16 One possible implementation manner of step 1502 is as shown in p (a) in 1 . The terminal device can modulate the third symbol sequence to obtain the fourth symbol sequence; after performing time-domain periodic extension on the fourth symbol sequence, Z p fourth symbol sequences are obtained; add the K Figure 16 modulated symbols at the end of the fourth symbol sequence to before the Z p fourth symbol sequences (corresponding to the operation of adding the CP sequence in p (a) of

[0576] ), to obtain Z p fourth symbol sequences and the first CP sequence located before the Z 1Before adding the first CP sequence, which consists of a modulation symbol, to the fourth symbol sequence, the first CP sequence and the fourth symbol sequence are also phase - continuous.

[0577] Since the modulation symbols obtained through modulation are continuous and can be sampled and stored in a digital system, after modulation, each modulation symbol obtained through modulation can be sampled. Sampling can be regarded as an independent operation. As shown in the figure, sampling is performed after modulation. Alternatively, sampling can also be regarded as part of modulation, in which case the sampling in the figure can be combined with modulation. This application does not make a limitation on this.

[0578] Assume that the sampling rate is S, where S is a positive integer. Then, S sample points are taken for each modulation symbol, and each modulation symbol can be recorded through the S sample points obtained by sampling. Since the third symbol sequence includes (N + M) symbols and (N + M) modulation symbols are obtained through modulation, (N + M)×S sample points can be obtained by sampling. In the embodiments of this application, the fourth symbol sequence can refer to the continuous (N + M) modulation symbols obtained through modulation, or the (N + M)×S sample points obtained through sampling. The (N + M) modulation symbols and the (N + M)×S sample points can be regarded as two different forms of the fourth symbol sequence.

[0579] Another possible implementation of step 1502 is as Figure 16 shown in (b) of. The terminal device can modulate the N symbols to be transmitted and the M extended symbols in the third symbol sequence respectively to obtain N continuous modulation symbols and M continuous modulation symbols. According to the positions of the M extended symbols in the third symbol sequence, the M modulation symbols are inserted into the N modulation symbols, and at least some of the modulation symbols in the N modulation symbols are phase - compensated so that the phases of the (M + N) modulation symbols after inserting the M modulation symbols are continuous (which can correspond to the splicing operation in (b) of Figure 16 ), thereby obtaining the fourth symbol sequence. After performing time - domain periodic extension on the fourth symbol sequence to obtain Z p fourth symbol sequences, the K 1 modulation symbols at the end of the fourth symbol sequence are added to the front of the Z p fourth symbol sequences, obtaining Z p fourth symbol sequences and the first CP sequence located in front of the Z p fourth symbol sequences.

[0580] Since the present application does not limit the positions of the M modulation symbols in the third symbol sequence, the M modulation symbols may be consecutive and located before or after the N symbols to be transmitted, or the M modulation symbols may also be distributed continuously or discretely among the N symbols to be transmitted. Due to the characteristic of the cumulative phase of CPM itself, when the M modulation symbols are inserted into the N symbols to be transmitted, the phase continuity between the inserted M modulation symbols and the N modulation symbols needs to be considered, so phase compensation is required. For the method of phase compensation of the fourth symbol, reference can be made to the description in combination with the example in the second implementation manner of step 6022 in the foregoing method 600, which will not be elaborated here.

[0581] Similar to Figure 16 (a) thereof, after modulating the N symbols to be transmitted and the M extended symbols, each modulated symbol obtained by modulation can also be sampled. Sampling can be regarded as an independent operation. As shown in the figure, sampling is performed after modulation, or sampling can also be regarded as a part of modulation. In this case, the sampling in the figure can be combined with modulation. The present application does not limit this.

[0582] Another possible implementation manner of step 1502 is as Figure 16 (c) shown. The terminal device can first perform time-domain periodic extension on the third symbol sequence to obtain Z p third symbol sequences; add the K 1 symbols at the end of the third symbol sequence to before the Z p third symbol sequences (corresponding to the operation of adding symbols in Figure 16 (c)) to obtain the eighth symbol sequence; modulate the eighth symbol sequence to obtain Z p fourth symbol sequences and the first CP sequence located before the Z p fourth symbol sequences.

[0583] That is to say, before modulation, first add the symbols for generating the first CP sequence to the third symbol sequence. Since the symbols for generating the first CP sequence are the K 1 symbols at the end of the third symbol sequence, and the third symbol sequence can make the fourth symbol sequence satisfy the head and tail phase self-loop, so add the K 1 symbols at its end to before the Z p third symbol sequences, and then modulate the obtained eighth symbol sequence. The phase between the obtained first CP sequence and the fourth symbol sequence is continuous, and the phase between the Z p fourth symbol sequences is also continuous. In this implementation manner, although the first CP sequence is modulated based on the K 1 symbols at the end of the third symbol sequence, it can be understood that the K 1The modulation symbols are also modulated based on the K symbols at the end of the third symbol sequence. Therefore, it can also be considered that the first CP sequence is the K modulation symbols at the end of the fourth symbol sequence. 1 Similar to (a) of 1 , after modulating the eighth symbol sequence, each modulated symbol obtained by modulation can be sampled. Sampling can be regarded as an independent operation. As shown in the figure, sampling is performed after modulation. Alternatively, sampling can also be regarded as part of the modulation. In this case, the sampling in the figure can be combined with the modulation. This application does not make any limitations in this regard.

[0584] And Figure 16 Similar to (a) of

[0585] Assume that the sampling rate is S. Then, the fourth symbol sequence obtained by modulating and sampling the eighth symbol sequence can be recorded by (N + M) × S sample points.

[0586] Figure 17 An example of the eighth symbol sequence is shown. Figure 17 It is assumed in 1 that the third symbol sequence is: {a 2 , a 3 , a ex}, where a 1 to a 3 are N symbols to be transmitted, and a ex are M extended symbols. The M extended symbols are located after the N symbols to be transmitted. Assume that the length K 1 of the first CP = 2. Then, the 2 symbols at the end of the third symbol sequence can be copied and added before Z p third symbol sequences to obtain the eighth symbol sequence {a 3 , a ex , a 1 , a 2 , a 3 , a ex , ……, a 1 , a 2 , a 3 , a ex}.

[0587] It should be understood that Figure 17 is shown only for ease of understanding and should not constitute any limitation to this application. This application does not make any limitations on the first symbol sequence, the third symbol sequence, N, M, K 1 , Z p , etc.

[0588] As described above in connection with Figure 16Among (a), (b), and (c), three different implementations of step 1502 are respectively shown. In these implementations, time-domain periodic extension is respectively performed on the third symbol sequence or the fourth symbol sequence. In fact, as already described in step 6022 of method 600 above, the terminal device may not necessarily perform the operation of time-domain periodic extension, that is, Z p can be equal to 1. Therefore, the operation of time-domain periodic extension in the figure is optional and can be skipped without execution.

[0589] In addition, regardless of whether time-domain periodic extension is performed on the third symbol sequence or the fourth symbol sequence, the position of the first CP sequence is before Z p fourth symbol sequences. Therefore, in step 1502, the terminal device can generate at least one fourth symbol sequence and the first CP sequence located before the at least one fourth symbol sequence based on the third symbol sequence.

[0590] In step 1503, the terminal device generates a first OFDM baseband signal based on the fourth symbol sequence and the first CP sequence.

[0591] The process of generating the OFDM baseband signal can be understood as the process of generating a time-domain signal. In this embodiment, the terminal device can generate a first OFDM baseband signal based on the value on each RE obtained after RE mapping and the first CP sequence. The specific process of step 1503 will be described below by taking CPM and LFM as examples respectively.

[0592] In one possible way, the first OFDM baseband signal satisfies:

[0593]

[0594] where the value range of t' satisfies: Δf is the subcarrier spacing; is a periodic function with a period of (N + M)×T, and its expression in 0 ≤ t' ≤ (N + M)×T is represents the third symbol sequence the phase at time t, the value range of t satisfies: 0 ≤ t ≤ (N + M)×T.

[0595] In formula 4, indicates that the CP of the first OFDM baseband signal (i.e., the first CP) is located before the body of the first OFDM baseband signal in the time domain. It is not difficult to see that the first OFDM baseband signal is continuous. For the description of other parameters, reference can be made to the relevant descriptions of formula 1 and formula 2 above, which will not be elaborated here.

[0596] It should be understood that Equation 4 is similar to Equation 1 shown in Method 600, except that Equation 1 has not inserted the first CP yet, while Equation 4 inserts the first CP at the time domain position before the OFDM symbol. Equation 4 is only an example, and those skilled in the art can also make simple transformations based on the same concept, such as that shown in Equation 4.1 below.

[0597] Assume that the symbol sequence composed of Z p fourth symbol sequences generated in step 1502 and the first CP sequence located before the Z p fourth symbol sequences is denoted as Then the first OFDM baseband signal generated based on the Z p fourth symbol sequences and the first CP sequence can satisfy:

[0598]

[0599] where, represents the phase of the third symbol sequence at time t, and can satisfy The value range of t satisfies: For the descriptions of other parameters, reference can be made to the relevant descriptions of Equation 1 and Equation 4 above, and details will not be repeated here. It can be more directly seen from Equation 4.1 that the first OFDM baseband signal is generated based on the Z p fourth symbol sequences and the first CP sequence.

[0600] One or more of the parameters used in CPM, such as the frequency pulse shaping function of CPM, the phase pulse shaping function of CPM, the modulation index of CPM, or the initial phase of CPM, can be configured by the network device or determined by the terminal device. This application does not make any limitations in this regard.

[0601] If the parameter is configured by the network device, the network device can indicate it to the terminal device through the fourth information, so that the terminal device can perform CPM based on the parameters indicated by the fourth information. Optionally, the method further includes: the terminal device receives the fourth information from the network device, or the network device sends the fourth information to the terminal device, and the fourth information is used to indicate the modulation parameters.

[0602] If the parameter is determined by the terminal device, the terminal device can indicate it to the network device through the fourth information, so that the network device can perform CPM demodulation based on the parameters indicated by the fourth information. Optionally, the method further includes: the terminal device sends the fourth information to the network device, or the network device sends the fourth information to the terminal device, and the fourth information is used to indicate the modulation parameters.

[0603] In the case where the modulation method is CPM, the modulation parameters may include, for example, at least one of the frequency pulse shaping function g(t) of CPM or the phase shaping function q(t) of CPM, the modulation index h of CPM, and the initial phase of CPM

[0604] In another possible way, the first OFDM baseband signal s(t', a) baseband Satisfies:

[0605]

[0606] Wherein, the value range of t' satisfies: Is a periodic function with a period of (N + M) × T, and the expression in 0 ≤ t' ≤ (N + M) × T is Represents the third symbol sequence The phase at time t, where the value range of t satisfies: 0 ≤ t ≤ (N + M) × T. It is not difficult to see that this first OFDM baseband signal is continuous.

[0607] It should be understood that this formula 5 is similar to formula 2 shown in method 600. The difference is that formula 2 does not insert the first CP, while formula 5 inserts the first CP at the time domain position before the OFDM symbol. Formula 5 is only an example, and those skilled in the art can also make simple transformations based on the same concept, such as shown in formula 5.1 below.

[0608] Assume that Z generated through step 1502 p The symbol sequence composed of the fourth symbol sequences and the first CP sequence located before the Z p The fourth symbol sequences is denoted as Then the first OFDM baseband signal generated based on the Z p The fourth symbol sequences and the first CP sequence can satisfy:

[0609]

[0610] Wherein, Represents the third symbol sequence The phase at time t, where the value range of t satisfies: For the description of other parameters, reference can be made to the relevant descriptions of formula 1 and formula 5 above, and details will not be repeated. It can be more directly seen from formula 5.1 that this first OFDM baseband signal is generated based on the Z p The fourth symbol sequences and the first CP sequence.

[0611] The parameters used in LFM, such as the bandwidth of the frequency band for transmitting the signal, can be configured by the network device or determined by the terminal device. This application does not make any limitations in this regard.

[0612] If the parameter is configured by the network device, the network device can indicate it to the terminal device through the fourth information, so that the terminal device can perform LFM based on the parameter indicated by the fourth information. Optionally, the method further includes: the terminal device receives the fourth information from the network device, or the network device sends the fourth information to the terminal device, and the fourth information is used to indicate the modulation parameter.

[0613] If the parameter is determined by the terminal device, the terminal device can indicate it to the network device through the fourth information, so that the network device can perform LFM demodulation based on the parameter indicated by the fourth information. Optionally, the method further includes: the terminal device sends the fourth information to the network device, or the network device sends the fourth information to the terminal device, and the fourth information is used to indicate the modulation parameter.

[0614] In the case where the modulation method is LFM, the modulation parameters can include, for example, the bandwidth F of the frequency band for transmitting the signal. In this embodiment, F can refer to the bandwidth of the frequency band for transmitting the first OFDM baseband signal, or the bandwidth of the target frequency band.

[0615] It should be understood that the formulas satisfied by the first OFDM baseband signal shown above are only examples given in combination with the formulas provided above. Those skilled in the art can, on this basis, make other possible mathematical transformations or equivalent replacements, and these mathematical transformations or equivalent replacements should all fall within the protection scope of this application.

[0616] As already mentioned in the foregoing method 600, upconversion is not limited to direct frequency modulation and can also be achieved through I / Q modulation. In this case, the first OFDM baseband signal generated by the terminal device based on the fourth symbol sequence and the first CP sequence is not limited to the form directly obtained through Formula 4, Formula 4.1, Formula 5, or Formula 5.1. The first OFDM baseband signal can include an I-channel baseband signal and a Q-channel baseband signal.

[0617] Taking CPM as an example, the I-channel baseband signal can be The Q-channel baseband signal can be Or, the I-channel baseband signal can be The Q-channel baseband signal can be The I-channel baseband signal and the Q-channel baseband signal can be respectively mixed by an I-channel mixer and a Q-channel mixer to perform frequency band shifting, and after superposition, a bandpass signal is obtained. Among them, regarding t and and t' and The definitions of parameters such as those can be referred to the relevant descriptions above in combination with Formula 4, Formula 4.1, Formula 5, and Formula 5.1, and will not be elaborated here.

[0618] In this embodiment, the time-domain resource of the first OFDM baseband signal can be an OFDM symbol, that is, the first OFDM baseband signal can be mapped to an OFDM symbol in the time domain. In other words, the above second symbol sequence can all be transmitted through one OFDM symbol. That is, the (N + M) × S time-domain samples used to carry the second symbol sequence can be transmitted through one OFDM symbol, and the transmission duration of each time-domain sample is: 1 / [(N + M) × S × Δf], where Δf is the subcarrier spacing and 1 / Δf is the duration of one OFDM symbol.

[0619] Optionally, the subcarrier spacing is predefined by the protocol or configured by the network device.

[0620] If the subcarrier spacing is configured by the network device, optionally, the method further includes: the terminal device receives the seventh information from the network device, or in other words, the network device sends the seventh information to the terminal device, and the seventh information is used to indicate the subcarrier spacing. By configuring the subcarrier spacing, the network device can implicitly indicate the duration of one OFDM symbol to the terminal device.

[0621] It should be noted that the subcarrier spacing can also be indicated by existing signaling. For example, in 5G, it can be indicated by the numerology index. In other words, the system bandwidth, the CP length corresponding to the system bandwidth, and the subcarrier spacing can be indicated by the numerology index.

[0622] In step 1504, the terminal device outputs a bandpass signal based on the first OFDM baseband signal.

[0623] In step 1505, the terminal device amplifies the power of the bandpass signal to obtain a power-amplified bandpass signal.

[0624] In step 1506, the terminal device transmits the power-amplified bandpass signal. Correspondingly, the network device receives the bandpass signal.

[0625] In step 1507, the network device obtains the first OFDM baseband signal based on the bandpass signal.

[0626] It should be understood that the specific processes of steps 1504 to 1507 are the same as those of steps 604 to 607 in the foregoing method 600, and can be referred to the relevant descriptions above, and will not be elaborated here.

[0627] In step 1508, the network device obtains the fourth symbol sequence based on the first OFDM baseband signal.

[0628] In step 1509, the network device obtains a third symbol sequence based on the fourth symbol sequence.

[0629] In step 1510, the network device obtains a first symbol sequence from the third symbol sequence.

[0630] Optionally, step 1510 includes:

[0631] The network device determines the value of M;

[0632] The network device determines the positions of M extended symbols in the third symbol sequence;

[0633] The network device obtains a first symbol sequence from the third symbol sequence.

[0634] The specific processes of steps 1508 to 1510 are the same as those of steps 608 to 610 in the foregoing method 600. For relevant descriptions, refer to the foregoing content and will not be elaborated herein.

[0635] In addition, for the specific implementation of each step of the network device in different forms of RAN, refer to the detailed description of method 600 and will not be elaborated herein.

[0636] In a possible implementation, steps 1501 to 1503 are implemented by the baseband chip of the terminal device, steps 1504 to 1505 are implemented by the radio frequency chip of the terminal device, the transmission action of step 1506 is implemented by the antenna of the terminal device, the reception action of step 1506 is implemented by the antenna of the network device, step 1507 is implemented by the radio frequency chip of the network device, and steps 1508 to 1510 are implemented by the baseband chip of the network device. To better understand this embodiment, the following will be combined with Figure 4 several different transmitter structures shown to illustrate the process of the terminal device from obtaining the first symbol sequence to transmitting the bandpass signal, and the process of the network device from receiving the bandpass signal to obtaining the first symbol sequence in the accompanying drawings.

[0637] Figure 18 (a), (b), and (c) in show the processing process of the terminal device.

[0638] As Figure 18As shown in (a) of [reference], after the terminal device obtains the first symbol sequence to be transmitted, it first expands the first symbol sequence to determine the third symbol sequence, and then modulates the third symbol sequence to obtain the fourth symbol sequence. As mentioned above, the fourth symbol sequence obtained by modulating the third symbol sequence is a continuous symbol sequence, and a discrete fourth symbol sequence can be obtained after sampling. For the sake of simplicity, the continuous fourth symbol sequence and the discrete fourth symbol sequence are not distinguished in the following text and drawings. It can be understood that whether it is a continuous fourth symbol sequence or a discrete fourth symbol sequence, they can all be collectively referred to as the fourth symbol sequence. The terminal device can perform time-domain periodic extension on the fourth symbol sequence to obtain Z p fourth symbol sequences, and then add the CP sequence to obtain Z p fourth symbol sequences and the first CP sequence located before Z p second symbol sequences. Thereafter, the terminal device can generate the first OFDM baseband signal based on Z p fourth symbol sequences and the first CP sequence. After obtaining the first OFDM baseband signal through the above baseband processing, the terminal device can directly frequency-modulate the carrier based on the first OFDM baseband signal to output a band-pass signal, and then perform power amplification on the band-pass signal, and transmit the power-amplified band-pass signal through the transmitting antenna. Among them, the power amplification includes non-linear power amplification or linear power amplification.

[0639] Figure 18 The processing process shown in (b) of [reference] is similar to that in Figure 18 (a), the difference lies in the way of obtaining the fourth symbol sequence. After the terminal device obtains the first symbol sequence to be transmitted, it first expands the first symbol sequence to determine the third symbol sequence, and then modulates and samples N symbols to be transmitted and M extended symbols in the third symbol sequence respectively to obtain N modulated symbols and M modulated symbols, and splices the N modulated symbols and M modulated symbols to obtain the fourth symbol sequence. The subsequent operations are the same as those in Figure 18 (a) and will not be elaborated here.

[0640] Figure 18 The process shown in (c) of [reference] is different from those in Figure 18 (a) and (b). After the terminal device obtains the first symbol sequence to be transmitted, it first expands the first symbol sequence to determine the third symbol sequence, and then performs periodic time-domain extension to obtain Z p third symbol sequences. The terminal de...

Claims

1. A communication method, characterized in that: include: Acquire a first symbol sequence, where the first symbol sequence includes N symbols to be transmitted, where N is a positive integer; Based on the first symbol sequence, a second symbol sequence is obtained, where symbols in the second symbol sequence are obtained by mapping (N+M) modulation symbols to resource elements RE, where the (N+M) modulation symbols are obtained based on modulating a third symbol sequence, where the third symbol sequence includes the N symbols to be transmitted and M extended symbols in the first symbol sequence, where the M extended symbols make the phases of the (N+M) modulation symbols obtained by the modulation continuous, and the difference between the phase at the starting position and the phase at the ending position is an integer multiple of 2π, where M is an integer greater than or equal to zero; A first orthogonal frequency division multiplexing (OFDM) baseband signal is generated based on the second symbol sequence, wherein the time domain resource of the first OFDM baseband signal is an OFDM symbol.

2. The method according to claim 1, characterized in that The modulation is continuous phase modulation CPM or linear frequency modulation LFM.

3. The method according to claim 1 or 2, characterized in that The method further comprises: The first OFDM baseband signal is sent.

4. The method according to any one of claims 1 to 3, characterized in that The frequency domain resources of the first OFDM baseband signal are (N+M)×S subcarriers, each of the (N+M)×S subcarriers is used to transmit a frequency domain sample point, the (N+M)×S frequency domain samples transmitted by the (N+M)×S subcarriers are obtained by performing Fourier transform on the (N+M)×S time domain samples, and the (N+M)×S time domain samples are obtained by sampling the (N+M) modulation symbols, and S is a positive integer.

5. The method according to claim 4, characterized in that The (N+M)×S subcarriers are continuous subcarriers; or, the (N+M)×S subcarriers are in a comb-teeth shape, and the subcarrier offsets between every two adjacent comb teeth are equal.

6. The method according to claim 5, characterized in that The (N+M)×S subcarriers are in a comb-tooth shape, and the method further includes: Receive or send first information, where the first information is used to indicate the subcarrier offset.

7. The method according to any one of claims 4 to 6, characterized in that The method further comprises: Receive or send second information, where the second information is used to indicate the S.

8. The method according to any one of claims 1 to 7, characterized in that The method further comprises: Third information is received, where the third information is used to indicate a length of a CP of the first OFDM baseband signal.

9. The method according to any one of claims 1 to 8, characterized in that The modulation is CPM, and the method further includes: Receive or send fourth information, where the fourth information is used to indicate one or more of the following: a frequency pulse shaping function, a phase pulse shaping function, a modulation index or an initial phase of the CPM.

10. The method according to any one of claims 1 to 8, characterized in that The modulation is LFM, and the method further comprises: Fourth information is received or sent, where the fourth information is used to indicate a frequency modulation slope of the LFM.

11. The method according to any one of claims 1 to 10, characterized in that The M is a positive integer, and the positions of the M extended symbols in the third symbol sequence are: before the N symbols to be transmitted, or after the N symbols to be transmitted, or continuously or discretely distributed among the N symbols to be transmitted.

12. The method according to any one of claims 1 to 11, characterized in that The method further comprises: receiving or sending fifth information, wherein the fifth information is used to indicate the positions of the M extended symbols in the third symbol sequence, and / or Receive or send sixth information, where the sixth information is used to indicate the M.

13. The method according to any one of claims 1 to 12, characterized in that The time domain resource of the first OFDM baseband signal is adjacent to the time domain resource of the second OFDM baseband signal, and the time domain resource of the second OFDM baseband signal is before the time domain resource of the first OFDM baseband signal, and the time domain resource of the second OFDM baseband signal is one OFDM symbol; The second OFDM baseband signal is generated based on a fifth symbol sequence, and the fifth symbol sequence is modulated based on a sixth symbol sequence, and the sixth symbol sequence includes P symbols to be transmitted and Q extended symbols, Q1 of the Q extended symbols are located in the first (P+Q-K2) symbols in the sixth symbol sequence, and Q2 of the Q extended symbols are located in the last K2 symbols in the sixth symbol sequence, and it is satisfied that the difference between the phase of the end position and the phase of the starting position of the modulation symbol sequence obtained by performing the modulation on the first (P+Q-K2) symbols is an integer multiple of 2π, and the difference between the phase of the end position and the phase of the starting position of the modulation symbol sequence obtained by performing the modulation on the last K2 symbols is also an integer multiple of 2π; wherein P is a positive integer, Q, Q1 and Q2 are integers greater than or equal to 0, K2 represents the length of the cyclic prefix CP of the second OFDM baseband signal, and K2 is an integer greater than 1; and M is an integer greater than 1, M1 of the M extended symbols are among the first (N+M-K1) symbols in the third symbol sequence, and M2 of the M extended symbols are among the last K1 symbols in the third symbol sequence, and satisfy: the modulation is performed on the first (N+M-K1) symbols, and the difference between the phase at the end position and the phase at the starting position of the obtained modulation symbol sequence is an integer multiple of 2π, and the difference between the initial phase of the modulation used to obtain the first OFDM baseband signal and the initial phase of the modulation used to obtain the second OFDM baseband signal is an integer multiple of 2π; wherein, M=M1+M2, M1 and M2 are both integers greater than or equal to 0, K1 represents the length of the CP of the first OFDM baseband signal, and K1 is an integer greater than 1.

14. The method according to any one of claims 1 to 13, characterized in that The method further comprises: A reference signal is sent, wherein the time domain resources of the reference signal are one or more OFDM symbols, and the time domain resources of the reference signal are different from the time domain resources of the first OFDM baseband signal, and the frequency domain resources of the reference signal are the same as the frequency domain resources of the second symbol sequence.

15. A baseband chip, characterized in that: Comprising means for implementing the method of any one of claims 1 to 14, claim 22 or 24 when dependent on any one of claims 1 to 14, or claim 23 or 25.

16. A communication device, characterized in that: include: The baseband chip as claimed in claim 15; The radio frequency chip is used to obtain a bandpass signal based on the first OFDM baseband signal from the baseband chip, and power amplify the bandpass signal to obtain the power-amplified bandpass signal.

17. The communication device according to claim 16, characterized in that The communication device further comprises: An antenna is used to transmit the power-amplified bandpass signal from the radio frequency chip.

18. The communication device according to claim 16 or 17, characterized in that: The radio frequency chip comprises: An up-conversion module, configured to directly frequency modulate a carrier based on the first OFDM baseband signal to obtain the passband signal; A power amplifier is used to power amplify the bandpass signal to obtain the power-amplified bandpass signal.

19. The communication device according to claim 18, characterized in that The up-conversion module includes: a phase-locked loop, a voltage-controlled oscillator or a digitally controlled oscillator.

20. The communication device according to claim 18 or 19, characterized in that: The power amplifier is a nonlinear power amplifier, which is used to perform nonlinear power amplification on the bandpass signal.

21. A communication method, characterized in that: include: Acquire a first orthogonal frequency division multiplexing (OFDM) baseband signal, wherein the time domain resource of the first OFDM baseband signal is an OFDM symbol; Based on the first OFDM baseband signal, obtain a fourth symbol sequence, wherein the fourth symbol sequence includes L modulation symbols, where L is a positive integer; Demodulating the fourth symbol sequence to obtain a third symbol sequence, where the third symbol sequence includes N first symbols and M extended symbols, where L=M+N, N is a positive integer less than or equal to L, and M is an integer greater than or equal to zero; Determining positions of the M and the M extended symbols in the third symbol sequence; The N first symbols are obtained from the third symbol sequence.

22. The method according to any one of claims 1 to 14 or 21, characterized in that The modulation is CPM, and M satisfies: 1≤M≤max{U+2, U+V-1}; wherein, V satisfies: h=W / V, and W / V is the simplest fraction, h is the modulation index of the CPM, U is a predefined value, and W, U and V are positive integers.

23. The method of claim 13, wherein: The modulation is CPM, the M satisfies: 2≤M≤2×max{U+2, U+V-1}, the Q satisfies: 2≤Q≤2×max{U+2, U+V-1}; wherein, the V satisfies: h=W / V, and W / V is the simplest fraction, the h is the modulation index of the CPM, the U is a predefined value, and the W, the U and the V are positive integers.

24. The method according to any one of claims 1 to 14 or 21, characterized in that The modulation is LFM, and M satisfies: 1≤M≤3.

25. The method of claim 13, wherein: The modulation is LFM, the M satisfies: 2≤M≤6; and the Q satisfies: 2≤Q≤6.

26. A communication device, characterized in that: Comprising modules for implementing the method as claimed in any one of claim 21, claim 22 or 24 when dependent on claim 21.

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