A multi-carrier wide-narrow band fusion transmission method and system based on chirp modulation

Abstract

The application discloses a multi-carrier wide / narrow band fusion transmission method and system based on chirp modulation, relates to the technical field of communication, and comprises the following steps: constructing a waveform framework, and splitting a bit stream to be sent at a sending end; modulating the bit stream obtained by splitting respectively; fusing the wide / narrow band chirp modulation signals obtained by modulation, and performing sending; at a receiving end, pre-processing the received signals, and demodulating the wide band chirp modulation signal and the narrow band chirp modulation signal obtained after pre-processing. The method of the application utilizes the pseudo-orthogonal characteristics existing between different slopes of chirp signals, realizes fusion of wide / narrow band chirp modulation waveforms, provides differentiated waveforms according to different service requirements in different scenes, and realizes complementary advantages between waveforms and efficient resource scheduling.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a multi-carrier wide-narrowband fusion transmission method and system based on chirp modulation. Background Art

[0002] Narrowband transmission services primarily involve low-rate, small-data-volume applications such as sensor data collection, remote monitoring, and IoT device communications. These services have low bandwidth requirements but are highly sensitive to network coverage, power consumption, and cost. Broadband transmission services, on the other hand, primarily serve high-data-rate applications such as video conferencing, high-speed data downloads, and cloud service access. For these services, users expect faster data transmission speeds and higher communication quality. Faced with diverse service demands in satellite and high-altitude airship coverage scenarios, and with limited aerospace access node resources, they require both broad geographic coverage to meet the coverage and cost requirements of narrowband services and high-speed data transmission capabilities to meet the challenges posed by broadband services.

[0003] Traditional broadband-narrowband converged transmission solutions typically design narrowband and broadband transmission services separately, achieving independent allocation of radio resources. While this solution met early communication service needs, its limitations have become increasingly apparent with technological advancements and the diversification of user demands. From a resource utilization perspective, independent design means fixed allocation of radio resources. This prevents the network from flexibly and efficiently allocating and utilizing resources when facing changing service demands, and may even result in resource waste. Furthermore, from a hardware design and deployment perspective, separate designs for broadband and narrowband services increase system hardware complexity. To address these issues, research and exploration of new transmission technologies that can integrate broadband and narrowband services and flexibly and efficiently utilize radio resources has become increasingly important. By breaking through traditional design and resource allocation methods, network performance and service quality can be effectively improved while reducing system complexity and operating costs, better meeting the diverse and high-quality demands of modern communication networks.

[0004] The paper [A. Bemani, N. Ksairi and M. Kountouris, "Affine Frequency Division Multiplexing for Next Generation Wireless Communications," in IEEE Transactions on Wireless Communications, vol. 22, no. 11, pp. 8214-8229, Nov. 2023, doi: 10.1109 / TWC.2023.3260906.] primarily analyzes the feasibility of a multicarrier wideband waveform based on chirp modulation. In terms of modulation, the paper exploits the pseudo-orthogonality between all chirp-modulated signals within the bandwidth, using the chirp-modulated signals as subcarriers. By directly weighting the QAM symbol information onto all subcarriers, the paper achieves an increase in transmission rate. By performing quantization analysis of the inter-symbol relationship between the transmitter and receiver in a dual-selective channel, it is found that the waveform effectively separates the delay and frequency offset characteristics. Therefore, the multicarrier wideband waveform based on chirp modulation can also be used for channel state information detection. However, considering that the use of wideband waveforms wastes a large number of subcarriers—that is, one subcarrier is used for pilot signals while the adjacent subcarriers do not store any bit information—transmission efficiency is significantly reduced. At the same time, wideband waveforms also place higher demands on the signal-to-noise ratio. Traditional chirped modulation signals can achieve high-precision delay and frequency offset estimation in applications with extremely low signal-to-noise ratios. Summary of the Invention

[0005] The embodiments of the present application provide a multi-carrier wide- and narrow-band fusion transmission method and system based on chirp modulation, which utilizes the pseudo-orthogonality between different slopes of chirp signals to achieve the fusion of wide- and narrow-band chirp modulation waveforms, provide differentiated waveforms according to different business requirements in different scenarios, and achieve complementary advantages between waveforms and efficient resource scheduling.

[0006] The present invention provides a chirp-modulated multi-carrier wide-narrowband fusion transmission method, including:

[0007] Construct a waveform frame and split the bit stream to be sent at the sending end;

[0008] Modulating the bit streams obtained by splitting respectively;

[0009] The wide-band and narrow-band chirp modulation signals obtained by modulation are combined and transmitted;

[0010] At the receiving end, the received signal is preprocessed, and the broadband chirp modulated signal and the narrowband chirp modulated signal obtained after the preprocessing are demodulated.

[0011] Optionally, constructing a waveform frame and splitting the bit stream to be sent at the transmitting end includes:

[0012] A mathematical model for chirp-modulated multi-carrier wide- and narrow-band fusion transmission is established to meet the following requirements:

[0013]

[0014] Where s(t) represents the time domain signal of the multi-carrier wide-narrowband fusion waveform based on chirp modulation, N RB Indicates the number of resource blocks, Indicates the number of subcarriers in a resource block, and the summation term k is the subcarrier index. A k′,l,i represents the complex modulation symbol, It also represents the subcarrier index, l is the time domain index, i represents the index of the narrowband waveform frequency change rate, e j2πk△ft is the inverse Fourier transform term, representing the broadband modulation (OFDM modulation) part, △f is the subcarrier spacing, is the narrowband modulation (chirp modulation) term, ν i represents the frequency change rate of the chirp signal, r represents the bandwidth occupancy ratio of the narrowband waveform, that is, r narrowband waveforms can be placed within the bandwidth of a wideband waveform;

[0015] Different frequency change rates are configured to make the chirp rates of the wideband and narrowband waveforms different, so as to utilize the pseudo-randomness brought by the chirp rate difference for waveform synchronization and data information demodulation;

[0016] At the initiator, the bit stream sequence to be sent is split according to the user needs of different receiving ends to obtain the bit stream for broadband transmission. and bit streams for narrowband transmission

[0017] Optionally, modulating the bit streams obtained by splitting includes:

[0018] For the bit stream obtained by splitting for broadband transmission Divide the bits into multiple groups according to the number of bits in a single symbol corresponding to QAM modulation, perform QAM modulation on any group of bits to obtain a QAM sequence, and then transform it through IDAFT to obtain a broadband chirp modulation signal;

[0019] For the bit stream obtained by splitting for narrowband transmission According to the symbol mapping, the symbol value information of the chirp modulation signal is obtained, and chirp modulation is performed based on the symbol value information to obtain a narrowband chirp modulation signal.

[0020] Optionally, fusing the modulated wideband and narrowband chirp modulation signals includes:

[0021] Dynamically allocate time and frequency resources of broadband chirp modulation signals and narrowband chirp modulation signals, where the bandwidth occupancy ratio of the narrowband waveform is r;

[0022] R narrowband modulated signal waveforms are embedded into a broadband chirp modulated signal to complete the fusion.

[0023] Optionally, at the receiving end, preprocessing the received signal includes:

[0024] Perform bandpass filtering according to the requirements of the receiving end to obtain the corresponding baseband signal;

[0025] Based on the baseband signal, capturing the broadband chirp modulation signal and the narrowband chirp modulation signal according to the bandwidth of the allocated broadband chirp modulation signal, and synchronizing using the preamble sequence in the narrowband chirp modulation signal;

[0026] For broadband transmission, a chirp modulation signal corresponding to a broadband frequency band is received to obtain a broadband and narrowband fused chirp modulation signal;

[0027] For narrowband transmission, bandpass filtering is performed according to the position of the allocated sub-band to obtain the corresponding narrowband chirp modulated signal with partial broadband signal interference;

[0028] The corresponding waveform is searched according to the resource S allocated by the receiving end, and the signal of the completed synchronization is recorded.

[0029] Optionally, after the preprocessing, demodulating the obtained broadband chirp modulated signal and the narrowband chirp modulated signal includes:

[0030] For broadband transmission, the wide-band and narrow-band fused chirped modulated signal is transformed by DAFT to obtain a QAM sequence, and broadband data bit stream information is obtained by QAM demodulation;

[0031] For narrowband transmission, the narrowband chirp modulated signal with partial broadband signal interference is chirped and demodulated to obtain the corresponding symbol value information, and then the symbol value is demodulated to obtain the narrowband partial data bit stream information.

[0032] The present application also provides a multi-carrier wide-narrowband fusion transmission system based on chirp modulation, including:

[0033] On the sending side:

[0034] The bit information splitting module splits the bit stream to be sent at the sending end according to the constructed waveform framework;

[0035] A modulation module, used to modulate the bit streams obtained by splitting;

[0036] The waveform fusion module is used to fuse the wide-band and narrow-band chirp modulation signals obtained by modulation;

[0037] On the receiving end:

[0038] A preprocessing module, used for preprocessing the received signal;

[0039] The demodulation module is used to demodulate the broadband chirp modulation signal and the narrowband chirp modulation signal obtained after preprocessing.

[0040] An embodiment of the present application also proposes a multi-carrier wide-narrowband fusion transmission device based on chirp modulation, including a memory and a processor, wherein a computer program is stored on the memory, and when the computer program is executed by the processor, the steps of the multi-carrier wide-narrowband fusion transmission method based on chirp modulation as described above are implemented.

[0041] The method of the embodiment of the present application utilizes the pseudo-orthogonality between different slopes of chirp signals to achieve the fusion of wide-band and narrow-band chirp modulation waveforms, provide differentiated waveforms according to different business needs in different scenarios, and realize complementary advantages between waveforms and efficient resource scheduling.

[0042] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0044] Figure 1 This is a basic flow diagram of the multi-carrier wide-narrowband fusion transmission method according to an embodiment of the present application;

[0045] Figure 2 This is a time-frequency diagram of the wide- and narrow-band waveforms of the multi-carrier wide- and narrow-band fusion transmission method according to an embodiment of the present application;

[0046] Figure 3 This is a schematic diagram of the wide-narrowband fusion waveform of the multi-carrier wide-narrowband fusion transmission method according to an embodiment of the present application;

[0047] Figure 4 This is a schematic diagram of the time-frequency relationship of the wide- and narrow-band fusion waveform after bandpass filtering in the multi-carrier wide- and narrow-band fusion transmission method according to an embodiment of the present application;

[0048] Figure 5 This is a schematic diagram of the architecture of a multi-carrier wide-narrowband fusion transmission system according to an embodiment of the present application. DETAILED DESCRIPTION

[0049] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0050] The embodiment of the present application provides a multi-carrier wide-narrowband fusion transmission method based on chirp modulation, such as Figure 1 As shown, the following steps are included:

[0051] In step S101, a waveform frame is constructed, and the bit stream to be sent is split at the transmitting end. In some embodiments, constructing a waveform frame and splitting the bit stream to be sent at the transmitting end includes:

[0052] A mathematical model for chirp-modulated multi-carrier wide- and narrow-band fusion transmission is established to meet the following requirements:

[0053]

[0054] Where s(t) represents the time domain signal of the multi-carrier wide-narrowband fusion waveform based on chirp modulation, N RB Indicates the number of resource blocks, Indicates the number of subcarriers in a resource block, and the summation term k is the subcarrier index. A k′,l,i represents the complex modulation symbol, It also represents the subcarrier index, l is the time domain index, i represents the index of the narrowband waveform frequency change rate, e j2πk△ft is the inverse Fourier transform term, representing the broadband modulation (OFDM modulation) part, △f is the subcarrier spacing, is the narrowband modulation (chirp modulation) term, v i represents the frequency change rate of the chirp signal, r represents the bandwidth occupancy ratio of the narrowband waveform, that is, r narrowband waveforms can be placed within the bandwidth of a wideband waveform;

[0055] Different frequency change rates are configured to make the chirp rates of the wide-band and narrow-band waveforms different, so as to utilize the pseudo-randomness brought by the chirp rate difference for waveform synchronization and data information demodulation, that is, utilizing the pseudo-randomness brought by the chirp rate difference to facilitate the subsequent waveform synchronization and data information demodulation.

[0056] At the initiator, the bit stream sequence to be sent is split according to the user needs of different receiving ends to obtain the bit stream for broadband transmission. and bit streams for narrowband transmission

[0057] In step S102, the bit streams obtained by splitting are modulated respectively. Specifically, the bit streams obtained by splitting are modulated respectively including:

[0058] For the bit stream obtained by splitting for broadband transmission Divide the bits into multiple groups according to the number of bits in a single symbol corresponding to QAM modulation, perform QAM modulation on any group of bits to obtain a QAM sequence, and then transform it through IDAFT to obtain a broadband chirp modulation signal;

[0059] For the bit stream obtained by splitting for narrowband transmission According to the symbol mapping, the symbol value information of the chirp modulation signal is obtained, and chirp modulation is performed based on the symbol value information to obtain a narrowband chirp modulation signal.

[0060] In step S103, the wideband and narrowband chirp modulated signals obtained by modulation are merged and transmitted. Specifically, the merging of the wideband and narrowband chirp modulated signals includes: dynamically allocating time and frequency resources of the wideband chirp modulated signal and the narrowband chirp modulated signal, where the bandwidth occupancy ratio of the narrowband waveform is r; and embedding the r narrowband modulated signal waveforms into a wideband chirp modulated signal to complete the fusion.

[0061] In step S104, at the receiving end, the received signal is preprocessed, and the broadband chirp modulated signal and the narrowband chirp modulated signal obtained after the preprocessing are demodulated. Specifically, at the receiving end, preprocessing the received signal includes:

[0062] Perform bandpass filtering according to the requirements of the receiving end to obtain the corresponding baseband signal;

[0063] Based on the baseband signal, capturing the broadband chirp modulation signal and the narrowband chirp modulation signal according to the bandwidth of the allocated broadband chirp modulation signal, and synchronizing using the preamble sequence in the narrowband chirp modulation signal;

[0064] For broadband transmission, a chirp modulation signal corresponding to a broadband frequency band is received to obtain a broadband and narrowband fused chirp modulation signal;

[0065] For narrowband transmission, bandpass filtering is performed according to the position of the allocated sub-band to obtain the corresponding narrowband chirp modulated signal with partial broadband signal interference;

[0066] Search for the corresponding waveform according to the resource S allocated by the receiving end, and record the signal that completes synchronization. For example, search for the corresponding waveform according to the resource S allocated by the receiving end, and save several copies of the current synchronized signal for subsequent waveform demodulation operations.

[0067] In some embodiments, after preprocessing, demodulating the obtained broadband chirp modulated signal and the narrowband chirp modulated signal includes:

[0068] For broadband transmission, the wide-band and narrow-band fused chirped modulated signal is transformed by DAFT to obtain a QAM sequence, and broadband data bit stream information is obtained by QAM demodulation;

[0069] For narrowband transmission, the narrowband chirp modulated signal with partial broadband signal interference is chirped and demodulated to obtain the corresponding symbol value information, and then the symbol value is demodulated to obtain the narrowband partial data bit stream information.

[0070] The embodiment of the present application also proposes an implementation case of a multi-carrier wide-narrowband fusion transmission method based on chirp modulation. In the embodiment of the present application, the spreading factor SF, the spectrum resource bandwidth B, the narrowband waveform bandwidth occupancy ratio r, and the resources allocated by the receiving end are described. For example, the narrowband waveform bandwidth occupancy ratio r means that r narrowband waveforms can be placed within the bandwidth of a wideband waveform. Represents the total resource allocation strategy, satisfying S = {{0}, P} and P is a power set of {1..., r}. And each element in P and O correspond to all transmission resources respectively, O represents broadband resources, 1 represents narrowband resources within the lth sub-bandwidth, 2 represents narrowband resources within the second sub-bandwidth, and so on until r represents narrowband resources within the rth sub-bandwidth. It is worth noting that the resource allocation strategy does not take into account the situation where broadband resources and narrowband resources are co-occupied, that is,

[0071] In this embodiment, only one broadband chirp modulation waveform bandwidth is considered. Therefore, the entire bandwidth resource can be viewed as an extension of the bandwidth described in this method, namely, a generalization of the current wide- and narrowband fusion waveform using frequency division multiplexing. Under the premise of fixed transmitter and receiver modules, by enabling the conditions of each submodule, this method is backward compatible.

[0072] This example supports a spreading factor of SF = 12, a spectrum resource bandwidth of B = 20 MHz, and a narrowband waveform bandwidth occupancy ratio of r = 3. A system configuration with two user receivers is provided: one for broadband transmission services, with S1 = {0}, and the other for narrowband transmission services, with resource occupancy of S2 = {1, 3}. Data transmission can also be achieved with spreading factors between 7 and 11, any bandwidth range, any integer narrowband waveform bandwidth occupancy ratio, and any other non-overlapping resource allocation scenarios by varying the module configuration.

[0073] This example uses a chirp-modulated multi-carrier wide-narrowband fusion waveform to illustrate the implementation of the transmission method of the present application. The corresponding transmission system of the present application has a transmitting end and a receiving end. The method of the embodiment of the present application includes the following steps:

[0074] Step A1: The transmitting end splits the bit stream to be sent. Specifically, the transmitting end splits the bit stream sequence to be sent according to the needs of different receiving ends to obtain the bit stream for broadband transmission. and bit streams for narrowband transmission

[0075] Step A2: modulate the bit streams obtained by splitting in step A1. Figure 2 As shown, for broadband transmission, the bit stream According to the number of bits in a single symbol corresponding to QAM modulation, multiple groups of bits are obtained, and then each group of bits is modulated by QAM to obtain a QAM sequence, which is then transformed by IDAFT to obtain a broadband chirp modulation signal. For narrowband transmission, the bit stream is converted to According to the symbol mapping, the symbol value information of the chirp modulated signal is obtained, and chirp modulation is performed based on the symbol value information to directly obtain a narrowband chirp modulated signal.

[0076] Step A3: The wideband and narrowband chirp modulation signals obtained in step A2 are merged. Specifically, the time and frequency resources of the wideband chirp modulation signal and the narrowband chirp modulation signal are dynamically allocated. Since the narrowband waveform bandwidth occupancy ratio r is 3, three narrowband chirp modulation signals can exist simultaneously within the bandwidth of a wideband chirp modulation signal, such as Figure 3 As shown, the three narrowband modulated signal waveforms are directly embedded in it, and the two signals are directly superimposed.

[0077] Step A4: Receive and pre-process the signal sent in step A3. Specifically, receive the signal sent in step A3 and perform band-pass filtering according to the needs of the receiving end, such as Figure 4As shown, the corresponding baseband signal is obtained. First, the broadband chirp modulation signal and the narrowband chirp modulation signal are captured according to the bandwidth of the allocated broadband chirp modulation signal, and then the preamble sequence in the narrowband chirp modulation signal is used for synchronization. Since the allocated resource S1 = {0} for user 1, i.e., broadband service transmission, the received broadband and narrowband fusion signal is directly received for user 1. For user 2, whose allocated resource S2 = {1, 3}, the narrowband chirp modulation signals of the two sub-bandwidths are filtered according to the allocated sub-bandwidths of the first and third, respectively, to obtain two narrowband chirp modulation signals.

[0078] In step A5, the broadband chirp modulated signal and the narrowband chirp modulated signal obtained by preprocessing in step A4 are demodulated. Specifically, user 1 is first considered. The broadband and narrowband fusion signal obtained in step A4 is directly transformed through DAFT to obtain a QAM sequence, and then demodulated through QAM to obtain broadband data bit stream information. Next, user 2 is considered. Since the narrowband modulated signals in the first and third sub-bandwidths do not interfere with each other, information can be captured simultaneously through parallel demodulation of both. Since the modulation methods of the two are the same, the parallel demodulation modules of the two are completely consistent. Specifically, the corresponding symbol value information is directly obtained through chirp demodulation, and then the narrowband data bit stream information is obtained through symbol value demodulation. The data of the two are then integrated to finally obtain all the required bit stream information.

[0079] The method of the present application starts from the modulation and demodulation method of chirp modulated signals in wideband and narrowband transmission scenarios, and comprehensively utilizes the advantages of chirp modulated signals in wideband transmission, such as high speed, anti-interference and channel sensitivity in narrowband transmission, to explore a wideband and narrowband fusion transmission method for chirp modulated signals. In the method of the present application, the transmitter fuses the waveforms of the chirp modulated signal in the wideband scenario and the narrowband scenario, so that the two share the same time and frequency resources. The receiver extracts the corresponding information through the allocated resources, fully utilizing the advantages of wideband and narrowband waveforms while ensuring reliable transmission efficiency.

[0080] Although the traditional narrowband chirp modulation system can achieve accurate analysis of channel state information and realize information transmission with extremely low signal-to-noise ratio, it has the disadvantage of low transmission rate and is therefore not suitable for broadband communication scenarios. At the same time, although the traditional broadband chirp modulation system has a high transmission rate, if it is used to obtain channel state information, the system transmission efficiency will be relatively reduced. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation in this application takes into account the compatibility of narrowband systems for low signal-to-noise ratio transmission, the accuracy of channel state information acquisition, and the effectiveness of broadband communication for high-speed transmission.

[0081] The present application also provides a multi-carrier wide-narrowband fusion transmission system based on chirp modulation, including:

[0082] On the sending side:

[0083] The bit information splitting module splits the bit stream to be sent at the sending end according to the constructed waveform framework;

[0084] A modulation module, used to modulate the bit streams obtained by splitting;

[0085] The waveform fusion module is used to fuse the wide-band and narrow-band chirp modulation signals obtained by modulation;

[0086] On the receiving end:

[0087] A preprocessing module, used for preprocessing the received signal;

[0088] The demodulation module is used to demodulate the broadband chirp modulation signal and the narrowband chirp modulation signal obtained after preprocessing.

[0089] Specifically, such as Figure 5 As shown, the multi-carrier wide-narrowband fusion transmission system based on chirp modulation in this example may include:

[0090] Bit information diversion module: used to divert the bit stream sent by the transmitter according to the requirements of the receiver; the bit stream sequence sent is divided into broadband communication or narrowband communication according to the requirements of the receiver. The bit stream used for broadband communication will be divided into one group, and the bit stream used for narrowband communication will be divided into another group. The two groups of bit streams are sent to the modulation module respectively.

[0091] This module is mainly used to group the input bit stream sequences as needed. Because the modulation methods are different in different demand scenarios, although the final transmission resources are the same, in order to improve transmission efficiency, the two groups of modulated bit sequences are split and parallel processing is completed.

[0092] Modulation module: used to perform corresponding modulation on the bit sequence obtained from the diversion; for the bit stream sent in for broadband communication, QAM mapping is first performed to obtain a QAM sequence, and then the QAM sequence is transformed by IDAFT to obtain the corresponding broadband chirp modulation signal. For the bit stream sent in for narrowband communication, symbol mapping is first performed, and then chirp modulation is performed according to the symbol value information to obtain the corresponding narrowband chirp modulation signal. The obtained broadband chirp modulation signal and narrowband chirp modulation signal are then sent to the waveform fusion module.

[0093] This module primarily processes bitstream information in parallel, performing both wideband and narrowband chirp modulation. During the modulation process, wideband and narrowband modulation methods are independent of each other and do not overlap. Therefore, from a hardware design perspective, parallel modulation of the two methods is feasible.

[0094] Waveform fusion module: used to integrate the broadband chirp modulation signal and the narrowband chirp modulation signal sent by the modulation module; directly superimpose the time domain signals of the two in the time domain, and directly modulate the superimposed signal into the carrier and send it.

[0095] This module is mainly used to achieve the fusion of wide-band and narrow-band waveforms. By directly superimposing wide-band and narrow-band chirp modulation signals, signal transmission on common spectrum and time resources is realized.

[0096] The preprocessing module is used to preprocess the waveform received by the receiver. Preprocessing consists of three operations: bandpass filtering, waveform synchronization, and resource detection. Bandpass filtering primarily receives signals based on the allocated bandwidth resources. Waveform synchronization primarily performs synchronization and channel estimation based on the narrowband portion of the received wide- and narrowband fusion waveform. Resource detection primarily obtains the information index required by the receiver within the current bandwidth, helping the receiver determine which information belongs to it.

[0097] This module mainly helps the receiving end to pre-process the received signal to facilitate the subsequent demodulation of the information waveform. During the demodulation process, the required bit stream can be found based on the information in the resource detection.

[0098] The demodulation module extracts the information bits required by the receiver from the received signal after synchronization and channel estimation. For wideband chirp modulated signals, the DAFT transform is used to obtain the corresponding QAM sequence, which is then demodulated to obtain the wideband information bit stream. For narrowband chirp modulated signals, traditional chirp demodulation schemes are used to obtain the corresponding symbol values, which are then mapped to the bit stream information. The receiver then extracts the required bit stream based on the resource detection information and completes demodulation.

[0099] This module directly demodulates the bitstream information based on the weak interference between wideband and narrowband waveforms. Similar to the transmitter, the received signal undergoes both wideband and narrowband demodulation based on user-side service requirements. These two processes are independent of each other, allowing for parallel hardware operation to improve system efficiency.

[0100] An embodiment of the present application also proposes a multi-carrier wide-narrowband fusion transmission device based on chirp modulation, including a memory and a processor, wherein a computer program is stored on the memory, and when the computer program is executed by the processor, the steps of the multi-carrier wide-narrowband fusion transmission method based on chirp modulation as described above are implemented.

[0101] It should be noted that, in the various embodiments of the present application, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0102] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0103] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of the present application.

[0104] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are protected by this application.

Claims

1. A multi-carrier wide-narrowband fusion transmission method based on chirp modulation, characterized in that: include: Construct a waveform frame and split the bit stream to be sent at the sending end; Modulating the bit streams obtained by splitting respectively; The wide-band and narrow-band chirp modulation signals obtained by modulation are combined and transmitted; At the receiving end, the received signal is preprocessed, and the broadband chirp modulated signal and the narrowband chirp modulated signal obtained after the preprocessing are demodulated; Constructing a waveform frame and splitting the bit stream to be sent at the transmitter includes: A mathematical model for chirp-modulated multi-carrier wide- and narrow-band fusion transmission is established to meet the following requirements: in, represents the time domain signal of the multi-carrier wide-narrowband fusion waveform based on chirp modulation, Indicates the number of resource blocks, Indicates the number of subcarriers in a resource block, the sum is the subcarrier index, indivual, represents the complex modulation symbol, Also represents the subcarrier index, is the time domain index, An index representing the rate of change of frequency of a narrowband waveform, is the inverse Fourier transform term, representing the broadband modulation part, is the subcarrier spacing, is a narrowband modulation term, represents the frequency change rate of the chirp signal, r represents the bandwidth occupancy ratio of the narrowband waveform, that is, r narrowband waveforms can be placed within the bandwidth of a wideband waveform; Different frequency change rates are configured to make the chirp rates of the wideband and narrowband waveforms different, so as to utilize the pseudo-randomness brought by the chirp rate difference for waveform synchronization and data information demodulation; At the initiator, the bit stream sequence to be sent is split according to the user needs of different receiving ends to obtain the bit stream for broadband transmission. and bit streams for narrowband transmission .

2. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation according to claim 1, characterized in that: Modulating the bit streams obtained by splitting includes: For the bit stream obtained by splitting for broadband transmission , divide the bits according to the number of single symbols corresponding to QAM modulation to obtain multiple groups of bits, perform QAM modulation on any group of bits to obtain a QAM sequence, and obtain a broadband chirp modulation signal through IDAFT transformation; For the bit stream obtained by splitting for narrowband transmission , according to the symbol mapping, the symbol value information of the chirp modulated signal is obtained, and chirp modulation is performed according to the symbol value information to obtain a narrowband chirp modulated signal.

3. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation according to claim 2, characterized in that: The fusion of the wide-band and narrow-band chirp modulation signals obtained by modulation includes: Dynamically allocate time and frequency resources of broadband chirp modulation signals and narrowband chirp modulation signals, where the bandwidth occupancy ratio of the narrowband waveform is r; R narrowband modulated signal waveforms are embedded into a broadband chirp modulated signal to complete the fusion.

4. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation according to claim 3, characterized in that: At the receiving end, the preprocessing of the received signal includes: Perform bandpass filtering according to the requirements of the receiving end to obtain the corresponding baseband signal; Based on the baseband signal, capturing the broadband chirp modulation signal and the narrowband chirp modulation signal according to the bandwidth of the allocated broadband chirp modulation signal, and synchronizing using the preamble sequence in the narrowband chirp modulation signal; For broadband transmission, a chirp modulation signal corresponding to a broadband frequency band is received to obtain a broadband and narrowband fused chirp modulation signal; For narrowband transmission, bandpass filtering is performed according to the position of the allocated sub-band to obtain the corresponding narrowband chirp modulated signal with partial broadband signal interference; The corresponding waveform is searched according to the resource S allocated by the receiving end, and the signal of the completed synchronization is recorded.

5. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation according to claim 4, characterized in that: After preprocessing, the broadband chirp modulated signal and the narrowband chirp modulated signal are demodulated, including: For broadband transmission, the wide-band and narrow-band fused chirped modulated signal is transformed by DAFT to obtain a QAM sequence, and broadband data bit stream information is obtained by QAM demodulation; For narrowband transmission, the narrowband chirp modulated signal with partial broadband signal interference is chirped and demodulated to obtain the corresponding symbol value information, and then the symbol value is demodulated to obtain the narrowband partial data bit stream information.

6. A multi-carrier wide-narrowband fusion transmission system based on chirp modulation, characterized in that: include: On the sending side: The bit information splitting module splits the bit stream to be sent at the sending end according to the constructed waveform framework; A modulation module, used to modulate the bit streams obtained by splitting; The waveform fusion module is used to fuse the wide-band and narrow-band chirp modulation signals obtained by modulation; On the receiving end: A preprocessing module, used for preprocessing the received signal; A demodulation module, configured to demodulate the broadband chirp modulation signal and the narrowband chirp modulation signal obtained after preprocessing; Constructing a waveform frame and splitting the bit stream to be sent at the transmitter includes: A mathematical model for chirp-modulated multi-carrier wide- and narrow-band fusion transmission is established to meet the following requirements: in, represents the time domain signal of the multi-carrier wide-narrowband fusion waveform based on chirp modulation, Indicates the number of resource blocks, Indicates the number of subcarriers in a resource block, the sum is the subcarrier index, indivual, represents the complex modulation symbol, Also represents the subcarrier index, is the time domain index, An index representing the rate of change of frequency of a narrowband waveform, is the inverse Fourier transform term, representing the broadband modulation part, is the subcarrier spacing, is a narrowband modulation term, represents the frequency change rate of the chirp signal, r represents the bandwidth occupancy ratio of the narrowband waveform, that is, r narrowband waveforms can be placed within the bandwidth of a wideband waveform; Different frequency change rates are configured to make the chirp rates of the wideband and narrowband waveforms different, so as to utilize the pseudo-randomness brought by the chirp rate difference for waveform synchronization and data information demodulation; At the initiator, the bit stream sequence to be sent is split according to the user needs of different receiving ends to obtain the bit stream for broadband transmission. and bit streams for narrowband transmission .

7. A multi-carrier wide-narrowband fusion transmission device based on chirp modulation, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the multi-carrier wide-narrowband fusion transmission method based on chirp modulation are implemented as described in any one of claims 1 to 5.

Images