Signal sending method, apparatus, device, and medium

Abstract

The application provides a signal sending method, device, equipment and medium. The method comprises the following steps: obtaining a first constant modulus orthogonal frequency division multiplexing (OFDM) signal and a second signal; after adding a cyclic prefix and a cyclic postfix to the first constant modulus OFDM signal, performing windowing processing to obtain a perception signal; obtaining a communication signal based on the second signal; and sending the perception signal and the communication signal. The method of the application uses the constant modulus OFDM signal as the perception signal, the frequency spectrum of the waveform of which can be naturally Gaussian spectrum, and the signal with Gaussian spectrum is beneficial to perception detection. Moreover, after the windowing processing of the constant modulus OFDM signal, the out-of-band leakage of the perception signal is greatly reduced. Finally, the perception signal and the communication signal are sent together, and the integration of communication and perception is realized.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a signal transmission method, apparatus, device, and medium. Background Technology

[0002] Radar sensing and wireless communication are two common and important applications of modern radio technology, and they are designed and developed independently according to different functions and frequency bands. Radar is mainly used for target detection and identification, while communication aims to realize information transmission between devices. However, with the exponential increase in the number of wireless devices and the higher bandwidth requirements for high-speed data transmission, the electromagnetic spectrum has become excessively congested.

[0003] Current technologies use constant-mode orthogonal frequency division multiplexing (OFDM) signals for radar, resulting in significant out-of-band leakage. Furthermore, existing technologies generally only consider sensing or communication. Future technologies require simultaneous sensing and communication capabilities. How to design integrated sensing waveforms while minimizing out-of-band leakage to meet the requirements of practical communication remains a challenge, and current waveform designs do not adequately address these issues. Summary of the Invention

[0004] The purpose of this invention is to provide a signal transmission method, apparatus, device, and medium to solve the problem of how to design a sensing-integrated waveform to reduce out-of-band leakage.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a signal transmission method, comprising:

[0006] Acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal;

[0007] After adding a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, the sensing signal is obtained after windowing processing.

[0008] Based on the second signal, a communication signal is obtained;

[0009] The sensing signal and the communication signal are transmitted.

[0010] In some embodiments, acquiring the first constant-mode orthogonal frequency division multiplexing (OFDM) signal includes:

[0011] The first MK bits of a pseudo-noise PN sequence are modulated to obtain K symbols, generating a frequency domain signal with a conjugate symmetrical distribution in the frequency domain, where M and K are positive integers;

[0012] The frequency domain signal is processed by inverse fast Fourier transform (IFFT) to obtain the third signal;

[0013] Phase modulation is performed on the third signal to obtain a first constant-mode OFDM signal.

[0014] In some embodiments, the first constant-mode OFDM signal satisfies at least one of the following conditions:

[0015] The oversampling factor of the first constant-mode OFDM signal is greater than or equal to 8;

[0016] The phase modulation factor of the first constant mode OFDM signal has a value range of [1.2 / 2π, 1.75 / 2π].

[0017] In some embodiments, modulating the first MK bits of a pseudo-noise PN sequence to obtain K symbols includes:

[0018] Modulate the first MK bits of the pseudo-noise PN sequence to obtain K symbols using any of the following methods:

[0019] M-order orthogonal amplitude modulation (M-QAM);

[0020] M-order orthogonal phase shift keying (M-PSK); where M-order means that M bits are mapped to one symbol.

[0021] In some embodiments, the method further includes:

[0022] Before sending the sensing signal, the first waveform parameter sequence number is sent;

[0023] Wherein, the first waveform parameter number is the waveform parameter number corresponding to the sensing signal, the sensing signal is a signal generated according to the waveform parameters corresponding to the first waveform parameter number in the predefined sensing waveform set, and the waveform parameters are related to at least one of the following: Fourier transform (FFT) size, oversampling factor, phase modulation factor, frequency domain signal obtained after information bit modulation, and modulation method.

[0024] In some embodiments, sending the first waveform parameter sequence number includes:

[0025] The first waveform parameter sequence number is transmitted via the uplink control channel or the downlink control channel.

[0026] In some embodiments, the second signal is a second constant-mode OFDM signal; obtaining the communication signal based on the second signal includes:

[0027] After adding a cyclic prefix and a cyclic suffix to the second constant mode OFDM signal, and then performing windowing processing, the communication signal is obtained. The phase modulation factor of the second constant mode OFDM signal has a value range of [0.65 / 2π, 1 / 2π].

[0028] In some embodiments, the constant-mode OFDM symbol is an OFDM signal with constant amplitude or a peak-to-average power ratio of 0.

[0029] In some embodiments, the second signal is an OFDM signal; obtaining the communication signal based on the second signal includes:

[0030] After adding a cyclic prefix and a cyclic suffix to the OFDM signal, and then performing windowing processing, the communication signal is obtained; or,

[0031] The OFDM signal is filtered to obtain the communication signal.

[0032] In some embodiments, the length of the cyclic suffix is ​​greater than or equal to 5 sampling points.

[0033] In some embodiments, transmitting the sensing signal and the communication signal includes:

[0034] The sensing signal and the communication signal are transmitted by means of time-domain multiplexing or frequency-domain multiplexing.

[0035] In a second aspect, the present invention also provides a signal transmitting device, comprising:

[0036] The acquisition module is used to acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal;

[0037] The first processing module is used to add a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, and then perform windowing processing to obtain the sensing signal;

[0038] The second processing module is used to obtain a communication signal based on the second signal;

[0039] The first transmitting module is used to transmit the sensing signal and the communication signal.

[0040] Thirdly, the present invention also provides a communication device, which is a first communication device, comprising a processor and a transceiver, wherein the transceiver receives and transmits data under the control of the processor, and the processor is configured to perform the following operations:

[0041] Acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal;

[0042] After adding a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, the sensing signal is obtained after windowing processing.

[0043] Based on the second signal, a communication signal is obtained;

[0044] The sensing signal and the communication signal are transmitted via a transceiver.

[0045] Fourthly, the present invention also provides a communication device, which is a first communication device, including a memory, a processor, and a program stored in the memory and executable on the processor; when the processor executes the program, it implements the signal transmission method as described in the first aspect above.

[0046] Fifthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the signal transmission method as described in the first aspect above.

[0047] In a sixth aspect, the present invention also provides a computer program product, including computer instructions that, when executed by a processor, implement the steps in the signal transmission method described in the first aspect above.

[0048] The above-described technical solution of the present invention has at least the following beneficial effects:

[0049] In this embodiment of the invention, a first constant-mode orthogonal frequency division multiplexing (OFDM) signal and a second signal are acquired; a cyclic prefix and a cyclic suffix are added to the first constant-mode OFDM signal, and then windowed to obtain a sensing signal; a communication signal is obtained based on the second signal; the sensing signal and the communication signal are then transmitted. In this way, by using the constant-mode OFDM signal as the sensing signal, its waveform frequency domain spectrum can naturally achieve a Gaussian spectrum. A Gaussian spectrum signal is beneficial for sensing and detection. Moreover, after windowing the constant-mode OFDM signal, the out-of-band leakage of the obtained sensing signal is greatly reduced. Finally, the sensing signal and the communication signal are transmitted together to achieve integrated sensing and communication. Attached Figure Description

[0050] Figure 1 A flowchart illustrating a signal transmission method according to an embodiment of the present invention;

[0051] Figure 2 A schematic diagram illustrating the generation process of the constant-mode OFDM signal according to an embodiment of the present invention;

[0052] Figure 3 A schematic diagram showing the spectrum of a constant-mode OFDM signal according to an embodiment of the present invention;

[0053] Figure 4 A schematic diagram illustrating the windowing of a constant-mode OFDM signal according to an embodiment of the present invention;

[0054] Figure 5 This diagram illustrates the out-of-band leakage of the constant-mode OFDM signal after windowing processing according to an embodiment of the present invention.

[0055] Figure 6This diagram shows the radar ambiguity function of the sensing signal before windowing in an embodiment of the present invention.

[0056] Figure 7 This diagram shows the radar ambiguity function of the constant-mode OFDM signal after windowing, according to an embodiment of the present invention.

[0057] Figure 8 This diagram illustrates the distance resolution characteristics of the constant-mode OFDM signal before (and after) windowing, according to an embodiment of the present invention.

[0058] Figure 9 A schematic diagram of the module of the signal transmitting device according to an embodiment of the present invention;

[0059] Figure 10 This illustrates the hardware structure of the communication device in an embodiment of the present invention. Detailed Implementation

[0060] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0061] It should be noted that linear frequency modulated (LFM) signals are pulse compression signals widely used in radar, offering excellent ranging and velocity measurement performance. Meanwhile, in communication systems, binary data can be modulated by changing the parameters of the chirped signal, enabling highly reliable data transmission. However, this modulation method alters the signal bandwidth and duration, changing the radar's effective range and resolution, thus affecting its detection performance.

[0062] Chirp signals possess constant-mode characteristics, meaning their peak-to-average power ratio (PAPR) is 0 dB. This allows for the use of highly efficient power amplifiers and enables long-range radar detection. Furthermore, their compact spectrum and rapid out-of-band radiation reduction meet radar waveform requirements (e.g., fine range resolution, low sidelobes, low out-of-band leakage, high pulse compression ratio, constant-mode transmission, and ease of implementation). However, chirp signals are not ideal for communication; their classic spectral efficiency for communication is 0.013 b / s / Hz.

[0063] Gaussian spectrum signals are advantageous for radar detection. The advantages of using Gaussian spectrum signals for radar detection are as follows: 1) The sidelobe size can be adjusted, which is due to the close relationship between Fourier transform and waveform autocorrelation; 2) The out-of-band roll-off factor can be controlled to reduce transmitter signal distortion; 3) Notch signals can be generated to reduce interference to other user signals.

[0064] To obtain a chirp signal with a Gaussian spectrum, the chirp signal needs to be optimized, which requires extensive computation. Simultaneously, to achieve diversity and coherent combining, the transmitted signal typically needs to be constantly varied. Therefore, the receiver needs to continuously optimize based on the input signal to obtain the Gaussian spectrum, increasing system complexity. Most research using chirp signals as integrated waveforms focuses on radar-communication integration using phase modulation methods on traditional radar waveforms, which suffers from difficulties in ensuring the orthogonality of the integrated signal, inflexible parameter adjustment, and low communication transmission rates.

[0065] Current constant-mode OFDM signals can be used for communication and sensing. Due to their constant-mode waveform characteristics, they have a long detection range and are suitable for radar sensing. Using phase modulation and demodulation, constant-mode OFDM signals can also be used for communication. However, using constant-mode OFDM signals as radar signals (sensing signals) results in significant out-of-band leakage. Furthermore, current technologies generally only consider sensing or communication. Future technologies require simultaneous sensing and communication capabilities. How to design integrated sensing waveforms while reducing out-of-band leakage to meet the requirements of practical communication remains a challenge, and current waveform designs have not adequately addressed these issues.

[0066] To address the aforementioned problems, this invention provides a signal transmission method, apparatus, device, and medium. The method and apparatus are based on the same conceptual framework. Since the methods and apparatus solve problems based on similar principles, their implementations can be mutually referenced, and repeated details will not be elaborated further.

[0067] like Figure 1 The diagram shown is a flowchart illustrating a signal transmission method provided in an embodiment of the present invention. This method is applied to a first communication device, i.e., executed by the first communication device. Specifically, the method may include:

[0068] Step 101: Obtain the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal;

[0069] In this embodiment of the invention, the constant-mode OFDM symbol is an OFDM signal with constant amplitude or a peak-to-average power ratio (PAPR) of 0. The constant-mode OFDM symbol is constrained by the modulation method or signal generation algorithm to maintain a constant or approximately constant amplitude of the time-domain waveform, thereby significantly reducing the PAPR. In the frequency domain, the subcarrier is modulated using precoding or phase optimization algorithms (such as gradient descent) to ensure that the amplitude of the time-domain signal after the inverse fast Fourier transform (IFFT) is constant. Typical methods include using constant envelope modulation (such as PSK) instead of QAM, or introducing phase compensation in the frequency domain.

[0070] Because constant-mode OFDM signals have the advantage of a PAPR of 0dB, power amplifiers can be used efficiently, allowing the signal to be transmitted over longer distances. Constant-mode OFDM signals can be used for wireless communication. Like OFDM signals, they support wideband signal communication in wireless multipath fading channels; frequency domain equalization has lower complexity; and they are resistant to phase noise. Due to the efficient use of power amplifiers, constant-mode OFDM signals offer a 10dB performance gain compared to OFDM signals.

[0071] In some embodiments, step 101, acquiring the first constant-mode orthogonal frequency division multiplexing (OFDM) signal, includes:

[0072] Step 1011: Modulate the first MK bits of a pseudo-noise PN sequence to obtain K symbols, generating a frequency domain signal with a conjugate symmetrical distribution in the frequency domain, where M and K are positive integers;

[0073] Optionally, the first MK bits of the pseudo-noise PN sequence can be modulated to obtain K symbols using any of the following methods:

[0074] M-order Quadrature Amplitude Modulation (M-QAM);

[0075] M-order phase shift keying (PSK) modulation; where M-order means that M bits are mapped to one symbol.

[0076] It should be noted that binary phase shift keying (BPSK) can be regarded as M-QAM modulation with M=2.

[0077] Specifically, the first MK bits of a PN sequence are modulated using M-QAM or M-PSK to obtain K symbols [X1, X2, ..., X]. K The K symbols are then conjugate symmetrically distributed to generate a frequency domain signal that is conjugate symmetrically distributed in the frequency domain.

[0078] Optionally, the pseudo-noise PN sequence can be an m-sequence or a GLORD sequence. For example, it could be a 31-order m-sequence or a GLORD sequence as defined in LTE.

[0079] It should be noted that for a frequency domain signal with a conjugate symmetrical distribution, where the first subcarrier is 0 and the middle subcarriers are 0, the oversampling factor J = N / (K+2), where N is the size of the Fast Fourier Transform (FFT). The larger the oversampling factor J and the smaller K, the lower the data transmission rate.

[0080] Step 1012: Perform Inverse Fast Fourier Transform (IFFT) processing on the frequency domain signal to obtain the third signal;

[0081] Among them, the second signal obtained after performing IFFT processing on the frequency domain signal that has a conjugate symmetrical distribution in the frequency domain is a real number.

[0082] Step 1013: Phase modulation is performed on the third signal to obtain a first constant mode OFDM signal.

[0083] Specifically, the third signal (i.e., the real number) is multiplied by 2πh and modulated into phase to obtain the first constant-mode OFDM signal. Here, h is called the phase modulation factor of the constant-mode OFDM signal. Compared to the OFDM signal, the constant-mode OFDM signal has half the spectral efficiency of its equivalent modulation.

[0084] For the generation process of the above constant-mode OFDM signal, please refer to [link / reference]. Figure 2 As shown.

[0085] Among them, the spectrum of the constant-mode OFDM signal (see Figure 3 It is related to the modulation factor h. When the value of h is large, it makes... When the time-domain signal exhibits a high autocorrelation, a Gaussian spectrum can be obtained. Simultaneously, the autocorrelation sidelobes of the time-domain signal are low, while the main lobe is high, making it highly advantageous for sensing signal detection. However, when 2πh is small and the offset from 1.75 is significant, the autocorrelation of the constant-mode waveform is poor, making it unsuitable for signal detection. For communication, a value of 0.65 to 1 is suitable, as this results in a lower probability of phase transitions during receiver demodulation, leading to better bit error rate performance in communication applications.

[0086] Using constant-mode OFDM signals as sensing signals results in significant out-of-band leakage. Filtering the constant-mode OFDM signal with a filter leads to a non-constant-mode signal after filtering. Therefore, it is necessary to reduce out-of-band leakage without compromising the constant-mode characteristics of the signal.

[0087] Out-of-band leakage is a crucial parameter in communication systems. It needs to be below a certain threshold to reduce interference with other systems. The original constant-mode OFDM signal has a large out-of-band leakage, only 40 dB lower than the main lobe, which is insufficient for practical systems. Using filters to reduce out-of-band leakage would increase complexity and disrupt the constant-mode characteristic of the waveform, making it undesirable. This application uses time-domain windowing to reduce out-of-band leakage, specifically step 102.

[0088] Step 102: After adding a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, the signal is windowed to obtain the sensing signal;

[0089] Assuming the useful portion of the first constant-mode OFDM signal has a length of N, adding a cyclic prefix to the first constant-mode OFDM signal is done by placing the last N1 points of the useful portion of the first constant-mode OFDM signal before the useful portion, see [reference needed]. Figure 4 .

[0090] Adding a cyclic suffix to the first constant-mode OFDM signal is as follows: Place the first N² points of the useful portion of the first constant-mode OFDM signal after the useful portion. See [link to relevant documentation]. Figure 4 .

[0091] Optionally, the length of the cyclic suffix is ​​greater than or equal to 5 sampling points.

[0092] After adding a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, the length of the signal is N+N1+N2.

[0093] Next, a window function of length N+N1+N2 is generated. This window function is then multiplied by the signal S1 (of length N+N1+N2) obtained by adding a cyclic prefix and cyclic suffix to the first constant-modulus OFDM signal (i.e., windowing processing, see [link]). Figure 4 ), thus obtaining the sensing signal S2 (length is N+N1+N2).

[0094] To reduce the impact of windowing on the useful signal (the useful part of the constant-mode OFDM signal), the window function value needs to be adjusted so that the window function value corresponding to the N points of the useful signal is 1.

[0095] To reduce the overhead of the window function, the cyclic suffix N2 can be between 5 and 15. If the number of sampling points corresponding to the useful signal is greater than 128, the overhead of windowing (N2 = 5) is relatively small. Generally, the number of sampling points for the useful signal in a system is between 512 and 1024, so the overhead of windowing is very small and can be almost ignored.

[0096] After adding a cyclic prefix and cyclic suffix to the first constant-mode OFDM signal, and then performing windowing processing, the resulting sensing signal is shown in the diagram of out-of-band leakage corresponding to this sensing signal. Figure 5 When used for radar detection, its radar ambiguity function graph (see...) Figure 7 ) and without windows (see Figure 6 The components are almost identical, therefore there is virtually no loss in detection performance when used for detection. See also Figure 8 This is a schematic diagram of the distance resolution characteristics before (and after) windowing. In other words, the distance resolution characteristics before and after windowing are almost the same, with little loss.

[0097] Step 103: Based on the second signal, obtain the communication signal;

[0098] Step 104: Send the sensing signal and the communication signal.

[0099] The signal transmission method of this invention uses a constant-mode OFDM signal as a sensing signal. The frequency domain spectrum of its waveform can naturally be Gaussian spectrum. The Gaussian spectrum signal is beneficial for sensing and detection. Moreover, after windowing the constant-mode OFDM signal, the out-of-band leakage of the obtained sensing signal is greatly reduced. Finally, the sensing signal and the communication signal are transmitted together to realize the integration of sensing and communication.

[0100] Optionally, the first constant-mode OFDM signal satisfies at least one of the following conditions:

[0101] The oversampling factor of the first constant-mode OFDM signal is greater than or equal to 8;

[0102] The phase modulation factor of the first constant mode OFDM signal has a value range of [1.2 / 2π, 1.75 / 2π].

[0103] The oversampling factor of the constant-mode OFDM signal is a crucial parameter. When the oversampling factor J is small, such as J = 2 or 4, the out-of-band leakage is significant, and even windowing methods have limited effect. Therefore, to achieve an out-of-band leakage close to -60dB for the constant-mode OFDM signal, the oversampling factor J must be greater than or equal to 8. Furthermore, the phase modulation factor h of the constant-mode OFDM signal also affects the out-of-band leakage; a smaller phase modulation factor h results in smaller out-of-band leakage. In other words, the out-of-band leakage can be adjusted by modifying both the oversampling factor J and the phase modulation factor h.

[0104] It should be noted that constant-mode OFDM signals inherently possess both sensing and communication capabilities. However, due to the large oversampling factor of constant-mode OFDM signals, their spectral efficiency is relatively low, making it difficult to meet communication data rate requirements in certain scenarios. Therefore, this application employs multiple methods to achieve a trade-off between communication and sensing. When the communication data rate is low, both communication and sensing utilize constant-mode OFDM signals. When the communication data rate is high, sensing uses constant-mode OFDM signals, while communication uses OFDM signals.

[0105] Optionally, the second signal is a second constant-mode OFDM signal or an OFDM signal.

[0106] In some embodiments, the second signal is a second constant-mode OFDM signal; step 103 above, based on the second signal, obtains a communication signal, including:

[0107] After adding a cyclic prefix and a cyclic suffix to the second constant mode OFDM signal, and then performing windowing processing, the communication signal is obtained. The phase modulation factor of the second constant mode OFDM signal has a value range of [0.65 / 2π, 1 / 2π].

[0108] Optionally, the length of the cyclic suffix is ​​greater than or equal to 5 sampling points.

[0109] Here, the steps for adding a cyclic prefix and cyclic suffix to the second constant-mode OFDM signal and then windowing it are the same as those for adding a cyclic prefix and cyclic suffix to the first constant-mode OFDM signal and then windowing it, and will not be repeated here. It should be noted that a value of 2πh between 0.65 and 1 is more suitable for communication, that is, a constant-mode OFDM signal (i.e., the second constant-mode OFDM signal) with a phase modulation factor h ranging from [0.65 / 2π, 1 / 2π] is more suitable for communication. In this case, the probability of phase transition during phase demodulation by the receiver (i.e., the second communication device that receives the sensing signal and the communication signal) is low, resulting in better bit error rate performance when used for communication.

[0110] It should be noted that this embodiment corresponds to a scenario where both sensing and communication use constant-mode OFDM signals when the communication data rate is low.

[0111] In some embodiments, the second signal is an OFDM signal; step 103 above, based on the second signal, obtains a communication signal, including:

[0112] After adding a cyclic prefix and a cyclic suffix to the OFDM signal, and then performing windowing processing, the communication signal is obtained.

[0113] Optionally, the length of the cyclic suffix is ​​greater than or equal to 5 sampling points.

[0114] Here, the steps for adding a cyclic prefix and a cyclic suffix to the OFDM signal and then performing windowing processing are the same as those for adding a cyclic prefix and a cyclic suffix to the first constant modulus OFDM signal and then performing windowing processing, and will not be repeated here.

[0115] Alternatively, the OFDM signal can be filtered to obtain the communication signal.

[0116] It should be noted that this embodiment corresponds to a scenario where constant mode OFDM signal is used for sensing and OFDM signal is used for communication when the communication data rate is high.

[0117] Sensing can be divided into two modes: one is A transmits and A receives (i.e., the first communication device transmits and the first communication device receives), and the other is A transmits and B receives (i.e., the first communication device transmits and the second communication device receives). For A transmits and A receives, since A knows the transmitted signal, there is no problem in correlating the received signal. For A transmits and B receives, B does not know the transmitted signal, making it difficult to perform correlation operations on the received signal. To solve this problem, the present invention adopts the following solution: a set of sensing waveforms is predefined, and the waveform parameters in the set are used to generate a sensing signal. The waveform parameter sequence number corresponding to the waveform parameters is transmitted in the control signaling. After receiving the control signaling, B generates A's sensing signal locally and performs correlation processing with the received signal to obtain sensing information, such as distance and speed.

[0118] In a scenario where A sends and B receives, in some embodiments, the method of the present invention further includes:

[0119] Before sending the sensing signal, the first waveform parameter sequence number is sent;

[0120] Wherein, the first waveform parameter number is the waveform parameter number corresponding to the sensing signal, the sensing signal is a signal generated according to the waveform parameters corresponding to the first waveform parameter number in the predefined sensing waveform set, and the waveform parameters are related to at least one of the following: Fourier transform (FFT) size, oversampling factor, phase modulation factor, frequency domain signal obtained after information bit modulation, and modulation method.

[0121] As an optional embodiment, sending the first waveform parameter sequence number includes:

[0122] The first waveform parameter sequence number is transmitted via the uplink control channel or the downlink control channel.

[0123] It should be noted that the waveform parameters of the sensing waveform set are related to the Fourier transform (FFT) size N, oversampling factor J, phase modulation factor h, and the frequency domain signals X1, X2, ..., X obtained after information bit modulation. K It is related to the modulation method (M-order QAM or M-order PSK).

[0124] Where X1, X2, ..., X K An M-order PSK or M-order QAM (M=2) can be performed on the first MK bits of a PN sequence. n The PN sequence is obtained by modulation (where n is a positive integer). Optionally, the PN sequence can be generated using an m-sequence or a Gold sequence, or other easily generated sequences.

[0125] As an example, a set of sensing waveforms is shown in Table 1 and is defined as follows:

[0126] Table 1

[0127]

[0128]

[0129] In some embodiments, step 104 above, sending the sensing signal and the communication signal, includes sending the sensing signal and the communication signal by means of time-domain multiplexing or frequency-domain multiplexing.

[0130] The following examples illustrate how the method of the present invention is implemented.

[0131] Example 1

[0132] The sensing signal uses a constant mode OFDM signal. The oversampling factor J of the constant mode OFDM signal is 8, and the value range of the phase modulation factor h is [1.2 / 2π, 1.75 / 2π]. The constant mode OFDM signal is windowed, and the length of the cyclic suffix is ​​greater than or equal to 5 sampling points. The resulting processed constant mode OFDM signal (which is the sensing signal at this time) has very little out-of-band leakage.

[0133] The communication uses a constant-mode OFDM signal with an oversampling factor J of 8 and a phase modulation factor h ranging from [0.65 / 2π, 1 / 2π]. The constant-mode OFDM signal is windowed, and the length of the cyclic suffix is ​​greater than or equal to 5 sampling points. The modulation uses one of the following: BPSK, QPSK, 16QAM, 64QAM, 256QAM, 8PSK, 16PSK, 64PSK, or 256PSK. The resulting processed constant-mode OFDM signal (which is the communication signal at this time) has very little out-of-band leakage.

[0134] Example 2

[0135] The sensing signal uses a constant mode OFDM signal. The oversampling factor J of the constant mode OFDM signal is 8, and the value range of the phase modulation factor h is [1.2 / 2π, 1.75 / 2π]. The constant mode OFDM signal is windowed, and the length of the cyclic suffix is ​​greater than or equal to 5 sampling points. The resulting processed constant mode OFDM signal (which is the sensing signal at this time) has very little out-of-band leakage.

[0136] Communication uses OFDM signals. The OFDM signal is windowed, and the length of the cyclic suffix is ​​greater than or equal to 5 sampling points. The resulting constant-mode OFDM signal (which is the communication signal at this time) has very little out-of-band leakage.

[0137] Example 3

[0138] Define a set of sensing waveforms, whose parameters are modulated by the Fourier Transform (FFT) size N, oversampling factor J, phase modulation factor h, and information bits to obtain the frequency domain signal X1, X2, ..., X...K The modulation method (M-QAM or M-PSK) is relevant. Waveform parameter sequences are transmitted on the uplink or downlink control channel. In a transmit-B receive mode, B can reconstruct A's transmitted signal based on information obtained from control signaling. By performing signal correlation processing between the received signal and the reconstructed signal, sensing information, such as distance and speed, is obtained.

[0139] This invention utilizes constant-mode OFDM signals for radar detection. The frequency domain spectrum of its waveform can naturally achieve a Gaussian spectrum (without requiring signal processing optimization). Furthermore, windowing of the constant-mode OFDM signal significantly reduces out-of-band leakage while incurring relatively low overhead. Compared to Chirp waveforms, constant-mode OFDM signals support wideband signal transmission. Constant-mode OFDM is resistant to multipath fading channels, has low frequency domain equalization complexity, and is resistant to phase noise interference, which is particularly advantageous for high frequencies such as millimeter waves and terahertz.

[0140] Figure 9 The present invention also provides a signal transmitting device, which includes:

[0141] The acquisition module 901 is used to acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal;

[0142] The first processing module 902 is used to add a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, and then perform windowing processing to obtain the sensing signal;

[0143] The second processing module 903 is used to obtain a communication signal based on the second signal;

[0144] The first transmitting module 904 is used to transmit the sensing signal and the communication signal.

[0145] In some embodiments, the acquisition module 901 includes:

[0146] The first modulation unit is used to modulate the first MK bits of a pseudo-noise PN sequence to obtain K symbols, generating a frequency domain signal with a conjugate symmetrical distribution in the frequency domain, where M and K are positive integers;

[0147] The first processing unit is used to perform Inverse Fast Fourier Transform (IFFT) processing on the frequency domain signal to obtain the third signal;

[0148] The second modulation unit is used to perform phase modulation on the third signal to obtain a first constant mode OFDM signal.

[0149] In some embodiments, the first constant-mode OFDM signal satisfies at least one of the following conditions:

[0150] The oversampling factor of the first constant-mode OFDM signal is greater than or equal to 8;

[0151] The phase modulation factor of the first constant mode OFDM signal has a value range of [1.2 / 2π, 1.75 / 2π].

[0152] In some embodiments, the first modulation unit is specifically used for:

[0153] Modulate the first MK bits of the pseudo-noise PN sequence to obtain K symbols using any of the following methods:

[0154] M-order orthogonal amplitude modulation (M-QAM);

[0155] M-order phase shift keying modulation (PSK); where M-order means that M bits are mapped to one symbol.

[0156] In some embodiments, the device further includes:

[0157] The second transmitting module is used to transmit the first waveform parameter sequence number before transmitting the sensing signal;

[0158] Wherein, the first waveform parameter number is the waveform parameter number corresponding to the sensing signal, the sensing signal is a signal generated according to the waveform parameters corresponding to the first waveform parameter number in the predefined sensing waveform set, and the waveform parameters are related to at least one of the following: Fourier transform (FFT) size, oversampling factor, phase modulation factor, frequency domain signal obtained after information bit modulation, and modulation method.

[0159] In some embodiments, the second transmitting module includes:

[0160] The first transmitting unit is used to transmit the sequence number of the first waveform parameter through an uplink control channel or a downlink control channel.

[0161] In some embodiments, the second signal is a second constant-mode OFDM signal; correspondingly, the second processing module 903 includes:

[0162] The second processing unit is used to add a cyclic prefix and a cyclic suffix to the second constant mode OFDM signal, and then perform windowing processing to obtain the communication signal. The phase modulation factor of the second constant mode OFDM signal has a value range of [0.65 / 2π, 1 / 2π].

[0163] In some embodiments, the constant-mode OFDM symbol is an OFDM signal with constant amplitude or a peak-to-average power ratio of 0.

[0164] In some embodiments, the second signal is an OFDM signal; correspondingly, the second processing module 903 includes:

[0165] The third processing unit is used to add a cyclic prefix and a cyclic suffix to the OFDM signal, and then perform windowing processing to obtain the communication signal; or,

[0166] The fourth processing unit is used to filter the OFDM signal to obtain the communication signal.

[0167] In some embodiments, the length of the cyclic suffix is ​​greater than or equal to 5 sampling points.

[0168] In some embodiments, the first transmitting module 904 includes:

[0169] The second transmitting unit is used to transmit the sensing signal and the communication signal by means of time-domain multiplexing or frequency-domain multiplexing.

[0170] The signal transmitting device of this invention acquires a first constant-mode orthogonal frequency division multiplexing (OFDM) signal and a second signal; after adding a cyclic prefix and a cyclic suffix to the first constant-mode OFDM signal and performing windowing processing, a sensing signal is obtained; based on the second signal, a communication signal is obtained; and the sensing signal and the communication signal are transmitted. In this way, by using the constant-mode OFDM signal as the sensing signal, its waveform frequency domain spectrum can naturally achieve a Gaussian spectrum. A Gaussian spectrum signal is beneficial for sensing and detection. Moreover, after windowing the constant-mode OFDM signal, the out-of-band leakage of the obtained sensing signal is greatly reduced. Finally, the sensing signal and the communication signal are transmitted together to achieve integrated sensing and communication.

[0171] To better achieve the above objectives, such as Figure 10 As shown, this embodiment of the invention also provides a communication device, which is a first communication device, including a processor 1000 and a transceiver 1010. The transceiver 1010 receives and transmits data under the control of the processor 1000, and the processor 1000 is used to execute the following process:

[0172] Acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal;

[0173] After adding a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, the sensing signal is obtained after windowing processing.

[0174] Based on the second signal, a communication signal is obtained;

[0175] The sensing signal and the communication signal are transmitted via transceiver 1010.

[0176] In some embodiments, the processor 1000 is further configured to:

[0177] The first MK bits of a pseudo-noise PN sequence are modulated to obtain K symbols, generating a frequency domain signal with a conjugate symmetrical distribution in the frequency domain, where M and K are positive integers;

[0178] The frequency domain signal is processed by inverse fast Fourier transform (IFFT) to obtain the third signal;

[0179] Phase modulation is performed on the third signal to obtain a first constant-mode OFDM signal.

[0180] In some embodiments, the first constant-mode OFDM signal satisfies at least one of the following conditions:

[0181] The oversampling factor of the first constant-mode OFDM signal is greater than or equal to 8;

[0182] The phase modulation factor of the first constant mode OFDM signal has a value range of [1.2 / 2π, 1.75 / 2π].

[0183] In some embodiments, the processor 1000 is further configured to:

[0184] Modulate the first MK bits of the pseudo-noise PN sequence to obtain K symbols using any of the following methods:

[0185] M-order orthogonal amplitude modulation (M-QAM);

[0186] M-order phase shift keying modulation (PSK); where M-order means that M bits are mapped to one symbol.

[0187] In some embodiments, transceiver 1010 is further configured to:

[0188] Before sending the sensing signal, the first waveform parameter sequence number is sent;

[0189] Wherein, the first waveform parameter number is the waveform parameter number corresponding to the sensing signal, the sensing signal is a signal generated according to the waveform parameters corresponding to the first waveform parameter number in the predefined sensing waveform set, and the waveform parameters are related to at least one of the following: Fourier transform (FFT) size, oversampling factor, phase modulation factor, frequency domain signal obtained after information bit modulation, and modulation method.

[0190] In some embodiments, transceiver 1010 is further configured to:

[0191] The first waveform parameter sequence number is transmitted via the uplink control channel or the downlink control channel.

[0192] In some embodiments, the second signal is a second constant-mode OFDM signal; the processor 1000 is further configured to:

[0193] After adding a cyclic prefix and a cyclic suffix to the second constant mode OFDM signal, and then performing windowing processing, the communication signal is obtained. The phase modulation factor of the second constant mode OFDM signal has a value range of [0.65 / 2π, 1 / 2π].

[0194] In some embodiments, the constant-mode OFDM symbol is an OFDM signal with constant amplitude or a peak-to-average power ratio of 0.

[0195] In some embodiments, the second signal is an OFDM signal; the processor 1000 is further configured to:

[0196] After adding a cyclic prefix and a cyclic suffix to the OFDM signal, and then performing windowing processing, the communication signal is obtained; or,

[0197] The OFDM signal is filtered to obtain the communication signal.

[0198] In some embodiments, the length of the cyclic suffix is ​​greater than or equal to 5 sampling points.

[0199] In some embodiments, transceiver 1010 is further configured to:

[0200] The sensing signal and the communication signal are transmitted by means of time-domain multiplexing or frequency-domain multiplexing.

[0201] The communication device of this invention acquires a first constant-mode orthogonal frequency division multiplexing (OFDM) signal and a second signal; after adding a cyclic prefix and a cyclic suffix to the first constant-mode OFDM signal and performing windowing processing, a sensing signal is obtained; based on the second signal, a communication signal is obtained; and the sensing signal and the communication signal are transmitted. In this way, by using the constant-mode OFDM signal as the sensing signal, its waveform frequency domain spectrum can naturally achieve a Gaussian spectrum. A Gaussian spectrum signal is beneficial for sensing and detection. Moreover, after windowing processing the constant-mode OFDM signal, the out-of-band leakage of the obtained sensing signal is greatly reduced. Finally, the sensing signal and the communication signal are transmitted together to achieve integrated sensing and communication.

[0202] This invention also provides a communication device, which includes a first communication device, a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the various processes in the signal transmission method embodiments described above and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0203] This invention also provides a computer-readable storage medium storing a computer program. When executed by a processor, this program implements the various processes described in the signal transmission method embodiments above, achieving the same technical effects. To avoid repetition, it will not be described again here. The computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0204] This invention also provides a computer program product, including computer instructions. When the computer instructions are executed by a processor, they implement the various processes of the aforementioned signal transmission method embodiments and achieve the same technical effects. To avoid repetition, they will not be described again here.

[0205] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-readable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0206] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 A device for one or more processes and / or the functions specified in one or more boxes.

[0207] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce a paper article including an instruction means, the instruction means being implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0208] These computer program instructions can also be loaded onto a computer or other programmable data processing equipment, causing the computer or other programmable equipment to perform a series of operational steps to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0209] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A signal transmission method, characterized in that, include: Acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal; After adding a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, the sensing signal is obtained after windowing processing. Based on the second signal, a communication signal is obtained; The sensing signal and the communication signal are transmitted.

2. The method according to claim 1, characterized in that, The acquisition of the first constant-mode orthogonal frequency division multiplexing (OFDM) signal includes: The first MK bits of a pseudo-noise PN sequence are modulated to obtain K symbols, generating a frequency domain signal with a conjugate symmetrical distribution in the frequency domain, where M and K are positive integers; The frequency domain signal is processed by inverse fast Fourier transform (IFFT) to obtain the third signal; Phase modulation is performed on the third signal to obtain a first constant-mode OFDM signal.

3. The method according to claim 1 or 2, characterized in that, The first constant-mode OFDM signal satisfies at least one of the following conditions: The oversampling factor of the first constant-mode OFDM signal is greater than or equal to 8; The phase modulation factor of the first constant mode OFDM signal has a value range of [1.2 / 2π, 1.75 / 2π].

4. The method according to claim 2, characterized in that, The process of modulating the first MK bits of a pseudo-noise PN sequence to obtain K symbols includes: Modulate the first MK bits of the pseudo-noise PN sequence to obtain K symbols using any of the following methods: M-order orthogonal amplitude modulation (M-QAM); M-order phase shift keying modulation (PSK); where M-order means that M bits are mapped to one symbol.

5. The method according to claim 1, characterized in that, The method further includes: Before sending the sensing signal, the first waveform parameter sequence number is sent; Wherein, the first waveform parameter number is the waveform parameter number corresponding to the sensing signal, the sensing signal is a signal generated according to the waveform parameters corresponding to the first waveform parameter number in the predefined sensing waveform set, and the waveform parameters are related to at least one of the following: Fourier transform (FFT) size, oversampling factor, phase modulation factor, frequency domain signal obtained after information bit modulation, and modulation method.

6. The method according to claim 5, characterized in that, The transmission of the first waveform parameter sequence number includes: The first waveform parameter sequence number is transmitted via the uplink control channel or the downlink control channel.

7. The method according to claim 1, characterized in that, The second signal is a second constant-mode OFDM signal; obtaining the communication signal based on the second signal includes: After adding a cyclic prefix and a cyclic suffix to the second constant mode OFDM signal, and then performing windowing processing, the communication signal is obtained. The phase modulation factor of the second constant mode OFDM signal has a value range of [0.65 / 2π, 1 / 2π].

8. The method according to claim 1 or 7, characterized in that, The constant-mode OFDM symbol is an OFDM signal with constant amplitude or a peak-to-average power ratio of 0.

9. The method according to claim 1, characterized in that, The second signal is an OFDM signal; obtaining a communication signal based on the second signal includes: After adding a cyclic prefix and a cyclic suffix to the OFDM signal, and then performing windowing processing, the communication signal is obtained; or, The OFDM signal is filtered to obtain the communication signal.

10. The method according to claim 1, 7, or 9, characterized in that, The length of the cyclic suffix is ​​greater than or equal to 5 sampling points.

11. The method according to claim 1, characterized in that, The transmission of the sensing signal and the communication signal includes: The sensing signal and the communication signal are transmitted by means of time-domain multiplexing or frequency-domain multiplexing.

12. A signal transmitting device, characterized in that, include: The acquisition module is used to acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal; The first processing module is used to add a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, and then perform windowing processing to obtain the sensing signal; The second processing module is used to obtain a communication signal based on the second signal; The first transmitting module is used to transmit the sensing signal and the communication signal.

13. A communication device, wherein the communication device is a first communication device, comprising a processor and a transceiver, the transceiver receiving and transmitting data under the control of the processor, characterized in that, The processor is used to perform the following operations: Acquire the first constant-mode orthogonal frequency division multiplexing (OFDM) signal and the second signal; After adding a cyclic prefix and a cyclic suffix to the first constant mode OFDM signal, the sensing signal is obtained after windowing processing. Based on the second signal, a communication signal is obtained; The sensing signal and the communication signal are transmitted via a transceiver.

14. A communication device, wherein the communication device is a first communication device, comprising a memory, a processor, and a program stored in the memory and executable on the processor; characterized in that, When the processor executes the program, it implements the signal transmission method as described in any one of claims 1 to 11.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the signal transmission method as described in any one of claims 1 to 11.

16. A computer program product, characterized in that, It includes computer instructions that, when executed by a processor, implement the steps of the signal transmission method as described in any one of claims 1 to 11.

Images