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

Abstract

The invention discloses a multi-carrier wide-narrow band fusion transmission method and system based on chirp modulation, and relates to the technical field of communication, and the method comprises the steps: constructing a waveform frame, and carrying out the shunting of a to-be-transmitted bit stream at a transmitting end; respectively modulating the bit streams obtained by shunting; fusing the wide and narrow band chirp modulation signals obtained by modulation, and executing transmission; at a receiving end, received signals are preprocessed, and broadband chirp modulation signals and narrowband chirp modulation signals obtained after preprocessing are demodulated. According to the method disclosed by the invention, the fusion of the wide-band chirp modulation waveform and the narrow-band chirp modulation waveform is realized by utilizing the pseudo-orthogonal characteristic existing between different slopes of the chirp signal, the differentiated waveforms are provided according to different service requirements in different scenes, and advantage complementation between the waveforms and efficient resource scheduling are realized.

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 mainly involve low-rate, small-data-volume applications such as sensor data collection, remote monitoring, and IoT device communications. This type of service has low bandwidth requirements, but is highly sensitive to network coverage, power consumption, and cost. Broadband transmission services, on the other hand, mainly serve high-data-rate application scenarios such as video conferencing, high-speed data downloads, and cloud service access. For this type of service, users expect faster data transmission speeds and higher communication quality. Faced with the diverse business needs in satellite and high-altitude airship coverage scenarios, and with limited aerospace access node resources, it is necessary to cover a wide geographical range to meet the coverage and cost requirements of narrowband services, while also having high-speed data transmission capabilities to meet the challenges brought by broadband services.

[0003] In the traditional broadband and narrowband fusion transmission scheme, narrowband and broadband transmission services are usually designed separately to achieve independent division of wireless resources. Although this scheme can meet the needs of early communication services, its limitations are becoming increasingly prominent with the development of technology and the diversification of user needs. On the one hand, from the perspective of resource utilization, the independent design method means that the division of wireless resources is fixed, which makes it impossible for the network to flexibly and efficiently allocate and utilize resources when facing changing business needs, and may even cause waste of resources. On the other hand, from the perspective of hardware design and deployment, independent design for broadband and narrowband services will increase the complexity of system hardware. In response to these problems, it is particularly important to study and explore a new transmission technology that can integrate broadband and narrowband services and flexibly and efficiently utilize wireless resources. By breaking through the traditional design and resource division method, the performance and service quality of the network can be effectively improved, while reducing system complexity and operating costs, and better meeting the diversified and high-quality needs of modern society for communication networks.

[0004] The literature [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.] mainly analyzes the feasibility of multi-carrier broadband waveforms based on chirp modulation. In terms of modulation, the article uses the pseudo-orthogonality between all chirp modulated signals within the bandwidth, uses the chirp modulated signals as subcarriers, and directly weights the QAM symbol information to all subcarriers to achieve an increase in transmission rate. By performing a quantitative analysis of the symbols between the transmitter and the receiver on the received signal under the dual-selection channel, it can be found that the waveform has better achieved the separation of delay and frequency deviation characteristics. Therefore, the multi-carrier broadband waveform based on chirp modulation can also be used for the detection of channel state information. However, considering that a large number of subcarriers will be wasted when using broadband waveforms, that is, one subcarrier is used for pilot and its adjacent subcarriers do not store any bit information, the transmission efficiency will be greatly reduced. At the same time, the signal-to-noise ratio requirements of broadband waveforms are also increased accordingly, while traditional chirp modulation signals can achieve application scenarios with extremely low signal-to-noise ratios and can also achieve high-precision delay estimation and frequency offset estimation. 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-orthogonal characteristics 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 embodiment of the present application provides a multi-carrier wide-narrowband fusion transmission method based on chirp modulation, 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 sent;

[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 sending end includes:

[0012] A mathematical model of chirp-modulated multi-carrier wide-narrowband 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, represents 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 frequency change rate of the narrowband waveform, and 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 divided 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 respectively includes:

[0018] For the bit stream obtained by splitting for broadband transmission Divide the bits of a single symbol 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;

[0019] 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.

[0020] Optionally, fusing the wide-band and narrow-band chirp modulation signals obtained by modulation includes:

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

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

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

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

[0025] Based on the baseband signal, 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 the preamble sequence in the narrowband chirp modulation signal is used for synchronization;

[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 a corresponding narrowband chirp modulation 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 completing synchronization is recorded.

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

[0030] For broadband transmission, the wide-narrowband fused chirp modulation signal is transformed by DAFT to obtain a QAM sequence, and broadband partial 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 narrowband partial data bit stream information is obtained through symbol value demodulation.

[0032] The embodiment of the present application further proposes a multi-carrier wide-narrowband fusion transmission system based on chirp modulation, comprising:

[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 for modulating the bit streams obtained by the splitting respectively;

[0036] A 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-orthogonal characteristics 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 achieve 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 of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0044] Figure 1 The basic process diagram of the multi-carrier wide-narrowband fusion transmission method according to the embodiment of the present application is shown;

[0045] Figure 2 This is a time-frequency diagram of 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 a wide-narrowband fusion waveform of a 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-narrowband fusion waveform after bandpass filtering in the multi-carrier wide-narrowband fusion transmission method according to an embodiment of the present application;

[0048] Figure 5 The diagram 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] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the 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. On the contrary, 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 present application embodiment 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 of chirp-modulated multi-carrier wide-narrowband 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, represents 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 frequency change rate of the narrowband waveform, and 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 wide-band and narrow-band waveforms different, so that the pseudo-randomness brought by the chirp rate difference can be used for waveform synchronization and data information demodulation, that is, the pseudo-randomness brought by the chirp rate difference can be used to facilitate the subsequent waveform synchronization and data information demodulation.

[0056] At the initiator, the bit stream sequence to be sent is divided 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 the split are modulated respectively. Specifically, the bit streams obtained by the split are modulated respectively including:

[0058] For the bit stream obtained by splitting for broadband transmission Divide the bits of a single symbol 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;

[0059] 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.

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

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

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

[0063] Based on the baseband signal, 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 the preamble sequence in the narrowband chirp modulation signal is used for synchronization;

[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 a corresponding narrowband chirp modulation signal with partial broadband signal interference;

[0066] According to the resource S allocated by the receiving end, the corresponding waveform is searched and the signal of completed synchronization is recorded. For example, according to the resource S allocated by the receiving end, the corresponding waveform is searched and several copies of the current synchronized signal are saved for subsequent waveform demodulation operations.

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

[0068] For broadband transmission, the wide-narrowband fused chirp modulation signal is transformed by DAFT to obtain a QAM sequence, and broadband partial 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 narrowband partial data bit stream information is obtained through symbol value demodulation.

[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. The embodiment of the present application describes a method in which a spreading factor SF, a spectrum resource bandwidth B, a narrowband waveform bandwidth occupancy ratio r, and the resources allocated by the receiving end are 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 allocation strategy of total resources, satisfying S = {{0}, P} and P is the power set of {1..., r}. And each element in P corresponds to all transmission resources with O, O represents broadband resources, 1 represents narrowband resources in the lth sub-bandwidth, 2 represents narrowband resources in the second sub-bandwidth, and r represents narrowband resources in 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 occupied together, that is,

[0071] In the embodiment of the present application, only one broadband chirp modulation waveform bandwidth is considered, so the entire bandwidth resource can be regarded as an extension of the bandwidth described in the method of the present application, that is, based on the current wide-narrowband fusion waveform, frequency division multiplexing is used for promotion. Under the premise of fixing the transmitting and receiving end modules, by enabling the conditions of each submodule, the method of the present application has downward compatibility.

[0072] This example provides a system configuration that supports a spreading factor of SF = 12, a spectrum resource bandwidth of B = 20MHz, and a narrowband waveform bandwidth occupancy ratio of r = 3, and two user receiving ends. One user receiving end corresponds to a broadband transmission service, that is, S1 = {0}, and the other user receiving end corresponds to a narrowband transmission service, and its resource occupancy is S2 = {1, 3}. Data transmission can also be achieved under spreading factors of 7 to 11, any bandwidth range, any integer narrowband waveform bandwidth occupancy ratio, and any other non-overlapping resource allocation conditions by changing the configuration of each module.

[0073] This example uses a multi-carrier wide-narrowband fusion waveform based on chirp modulation to illustrate the implementation of the transmission method of the present application. The transmission system corresponding to the present application is provided with 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 divides the bit stream to be transmitted. Specifically, the transmitting end divides the bit stream sequence to be transmitted according to the requirements of different receiving ends to obtain the bit stream for broadband transmission. and bit streams for narrowband transmission

[0075] Step A2, modulating the bit streams obtained by the splitting in step A1 respectively. Specifically, Figure 2 As shown, for broadband transmission, the bit stream According to the number of single symbol bits 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 into According to the symbol mapping, the symbol value information of the chirp modulated signal is obtained, and chirp modulation is performed thereon 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 bandwidth occupancy ratio r of the narrowband waveform 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, three narrowband modulated signal waveforms are directly embedded therein, and the two signals are directly superimposed.

[0077] Step A4, receiving and preprocessing the signal sent in step A3. Specifically, the signal sent in step A3 is received and bandpass filtered 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 leading sequence in the narrowband chirp modulation signal is used for synchronization. Since the resource allocated to user 1 is S1={0}, that is, broadband service transmission, user 1 directly receives the received broadband and narrowband fusion signal. For user 2 with allocated resources S2={1, 3}, according to the allocated sub-bandwidths of the first and third, the narrowband chirp modulation signals of the two sub-bandwidths are filtered respectively to obtain two narrowband chirp modulation signals.

[0078] Step A5, demodulate the broadband chirp modulation signal and the narrowband chirp modulation signal obtained by preprocessing in step A4. Specifically, first consider user 1, directly transform the broadband and narrowband fusion signal obtained in step A4 through DAFT to obtain a QAM sequence, and then demodulate through QAM to obtain broadband partial data bit stream information. Secondly, consider user 2. Since the narrowband modulation signals in the first and third sub-bandwidths do not interfere with each other, the two can be simultaneously captured through parallel demodulation. 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 partial data bit stream information is obtained through symbol value demodulation. Then the data of the two are 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 the chirp modulated signal in the wide-band and narrow-band transmission scenarios, and comprehensively utilizes the advantages of the chirp modulated signal in broadband transmission, anti-interference and channel sensitivity in narrow-band transmission, and intends to explore the wide-band and narrow-band fusion transmission method of the chirp modulated signal. In the method of the present application, the transmitter fuses the waveforms of the chirp modulated signal in the broadband scenario and the narrow-band scenario, so that the two share the same time and frequency resources, and the receiver extracts the corresponding information through the allocated resources, making full use of the advantages of the wide-band and narrow-band 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 coordinates 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 embodiment of the present application further proposes a multi-carrier wide-narrowband fusion transmission system based on chirp modulation, comprising:

[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 for modulating the bit streams obtained by the splitting respectively;

[0085] A 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, Figure 5 As shown, the chirp modulation-based multi-carrier wide-narrowband fusion transmission system of this example may include:

[0090] Bit information diversion module: used to divert the bit stream sent by the transmitter according to the needs of the receiver; the bit stream sequence sent is divided into broadband communication or narrowband communication according to the needs of the receiver, where 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, and the two groups of bit streams will be 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 the transmission efficiency, the two groups of bit sequences to be modulated are split and parallel processing is completed.

[0092] Modulation module: used to perform corresponding modulation on the bit sequence obtained by the diversion; for the bit stream sent in for broadband communication, QAM mapping is first performed to obtain the QAM sequence, and then the corresponding broadband chirp modulation signal is obtained through IDAFT transformation; 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, and then the obtained broadband chirp modulation signal and narrowband chirp modulation signal are sent to the waveform fusion module.

[0093] This module mainly processes the bit stream information in parallel and performs wide-band and narrow-band chirp modulation respectively. In the modulation process, there is no correlation between the wide-band and narrow-band modulation methods, that is, the two are independent of each other and do not overlap. Therefore, from the perspective of hardware design, parallel modulation of the two can be considered.

[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 perform carrier modulation on the superimposed signal 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] Preprocessing module: used to preprocess the waveform received by the receiver; preprocessing includes three operations, namely bandpass filtering, waveform synchronization and resource detection. Bandpass filtering mainly receives signals based on the allocated bandwidth resources. Waveform synchronization mainly performs synchronization and channel estimation based on the narrowband signal in the received wide-narrowband fusion waveform. Resource detection mainly obtains the information index required by the receiver within the current bandwidth, that is, helps the receiver confirm which part of the information belongs to the receiver.

[0097] This module mainly helps the receiving end to pre-process the received signal so as to demodulate the waveform of the information part later. During the demodulation process, the required bit stream can be found according to the information in the resource detection.

[0098] Demodulation module: used to extract the information bits required by the receiving end from the received signal that has completed synchronization and channel estimation. For broadband chirp modulation signals, the corresponding QAM sequence is directly obtained according to DAFT transformation, and then the broadband information bit stream is obtained through QAM demodulation. For narrowband chirp modulation signals, the corresponding symbol value is directly obtained through the traditional chirp demodulation scheme, and then the bit stream information is mapped through the symbol value. Therefore, the receiving end takes out the required bit stream according to the resource detection information and completes the demodulation.

[0099] This module mainly demodulates the bit stream information directly based on the weak interference characteristics between wideband and narrowband waveforms. Similar to the transmitter, the received signal is demodulated by broadband and narrowband respectively according to the user's service needs. The two are independent of each other, so they can also be implemented through parallel operation on hardware to improve the operating efficiency of the system.

[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 "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0102] The serial numbers of the above-mentioned 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 a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an 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, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a 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 the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present 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 sent; 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.

2. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation as claimed in claim 1, characterized in that: Constructing a waveform frame and splitting the bit stream to be sent at the sending end includes: A mathematical model of chirp-modulated multi-carrier wide-narrowband fusion transmission is established to meet the following requirements: 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, represents 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 frequency change rate of the narrowband waveform, and 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; 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 divided according to the user needs of different receiving ends to obtain the bit stream for broadband transmission. and bit streams for narrowband transmission 3. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation as claimed in claim 2, characterized in that: Modulating the bit streams obtained by splitting includes: For the bit stream obtained by splitting for broadband transmission Divide the bits of a single symbol 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.

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

5. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation as claimed in claim 4, characterized in that: At the receiving end, the preprocessing of the received signal includes: Perform bandpass filtering according to the needs of the receiving end to obtain the corresponding baseband signal; Based on the baseband signal, 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 the preamble sequence in the narrowband chirp modulation signal is used for synchronization; 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 a corresponding narrowband chirp modulation 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 completing synchronization is recorded.

6. The multi-carrier wide-narrowband fusion transmission method based on chirp modulation as claimed in claim 5, characterized in that: After preprocessing, the broadband chirp modulated signal and the narrowband chirp modulated signal are demodulated including: For broadband transmission, the wide-narrowband fused chirp modulation signal is transformed by DAFT to obtain a QAM sequence, and broadband partial 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 narrowband partial data bit stream information is obtained through symbol value demodulation.

7. 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 for modulating the bit streams obtained by the splitting respectively; A 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; The demodulation module is used to demodulate the broadband chirp modulation signal and the narrowband chirp modulation signal obtained after preprocessing.

8. 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 6.

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