Communication signal processing method, device, equipment and storage medium

Abstract

The present application discloses a communication signal processing method, device, equipment and storage medium, which relates to the field of wireless communication physical layer transmission technology, including: the transmitting end determines a reference sequence and a spread spectrum sequence based on the waveform parameters and spread spectrum factor of the Gaussian minimum shift keying waveform of the communication signal; the spread spectrum sequence is matched with the reference sequence, and a spread spectrum sequence mapping table is constructed according to the corresponding correspondence; the original information sequence of the communication signal is shift-mapped according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, the spread spectrum sequence is modulated, and the corresponding modulated signal is sent to the receiving end so that the receiving end can demodulate and despread the modulated signal. It can be seen that the present application can support non-spread spectrum and transceiver communications with different spread spectrum factors, and can more fully obtain the spread spectrum gain.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication physical layer transmission technology, and in particular to a communication signal processing method, device, equipment and storage medium. Background Art

[0002] In typical communication scenarios such as deep space tracking and control, manned space flight, and satellite-to-missile and missile-to-missile data links, the communication environment is characterized by strong interference and rapid signal attenuation. In addition, the transmission distance is usually long and the payload weight (power) is limited, requiring the receiver to correctly demodulate and receive the signal under extremely low signal-to-noise ratio conditions.

[0003] Gaussian Minimum-Shift Keying (GMSK) has the advantages of constant envelope and high spectrum utilization. It is suitable for communication systems with adjacent channel interference and nonlinear power amplifiers. It is a classic modulation method in measurement and control links and can be used as an excellent modulation waveform choice in the above communication scenarios. The demodulation methods of GMSK signals can be divided into coherent demodulation and incoherent demodulation. The coherent demodulation method requires strict carrier phase synchronization, the overall system implementation is complex, and the anti-interference ability is weak; while the incoherent demodulation method has a relatively simple structure, good robustness to frequency deviation and phase deviation, and better anti-interference ability, but the traditional incoherent demodulation performance deteriorates a lot.

[0004] Spread spectrum technology uses a high-code-rate spread spectrum sequence to expand the spectrum of the transmitted signal. On the basis of time-frequency synchronization, the receiver uses the same spread spectrum sequence to restore the original signal while suppressing interference to obtain spread spectrum gain. It has the advantages of strong anti-interference ability, multi-user multiple access and low interception probability, and can well adapt to the needs of the above communication scenarios. In the spread spectrum system, only by despreading the received signal to improve the input signal-to-noise ratio of the demodulation can the spread spectrum gain be fully obtained. The reception system of demodulation first and then despreading is usually limited in the utilization of the spread spectrum gain. In incoherent demodulation, this phenomenon is particularly obvious due to the amplification effect of demodulation on noise. As a continuous phase modulation waveform, GMSK has a memory that determines that the correlation peak cannot be obtained when the local pseudo code sequence is correlated with the received signal, and it is difficult to process the signal by first despreading and then demodulating. Considering the combination of GMSK waveform and spread spectrum technology, the processing methods of coherent demodulation and first despreading and then demodulating have the characteristics of weak anti-interference ability and great difficulty in implementation. Therefore, it is urgent to study the spread spectrum method that can relatively fully utilize the spread spectrum gain and the corresponding incoherent receiving processing method.

[0005] There are two main signal processing methods in the existing GMSK spread spectrum system: the first method directly chooses to adopt the processing of demodulation before despreading in the face of the difficulty of despreading before demodulation, and adds spread spectrum and despreading modules at both ends of the modulation and demodulation of the system. By correlating the local pseudo code sequence with the demodulated output, the original information sequence is determined. This method has a good knowledge foundation in spread spectrum and despreading methods, low design and implementation complexity, and simple structure, which is easy to directly integrate into the architecture of the transceiver system. However, since this method demodulates the received signal first, the signal-to-noise ratio of its input is not improved. The demodulation error at a low signal-to-noise ratio limits the efficiency of the back-end despreading module, which is not conducive to the utilization of spread spectrum gain. The second method adopts the processing mode of joint demodulation and despreading, adds a spread spectrum module to the modulation front end of the system, and combines the demodulation and despreading modules of the receiving end by combining the relevant methods into the demodulation algorithm. The received signal can directly determine the original information sequence through this module. This method requires specific algorithm design for the joint demodulation and despreading method and even the spread spectrum method. Compared with the first method, its design and implementation complexity is higher, and it usually requires targeted modifications to the framework of the transceiver system. However, due to the combination of the demodulation and despreading modules, its signal-to-noise ratio loss is smaller, the error transmission effect is less obvious, and at the same time, the loss of spread spectrum gain is smaller. Therefore, how to obtain the spread spectrum gain more fully to achieve reliable communication under extremely low signal-to-noise ratio conditions is an urgent problem to be solved. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a communication signal processing method, device, equipment and storage medium, which can make fuller use of the spread spectrum gain to ensure reliable communication under extremely low signal-to-noise ratio conditions. The specific scheme is as follows:

[0007] In a first aspect, the present application discloses a communication signal processing method, which is applied to a transmitting end, comprising:

[0008] Determine a reference sequence and a spread spectrum sequence based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of a communication signal;

[0009] Matching the spread spectrum sequence with the reference sequence, and constructing a spread spectrum sequence mapping table according to the corresponding correspondence;

[0010] The original information sequence of the communication signal is shift-mapped according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, the spread spectrum sequence is modulated, and the corresponding modulated signal is sent to a receiving end so that the receiving end can demodulate and despread the modulated signal.

[0011] Optionally, the determining of the reference sequence and the spread spectrum sequence based on the waveform parameters and the spread spectrum factor of the Gaussian minimum shift keying waveform of the communication signal includes:

[0012] Determine the Gaussian filter normalized bandwidth of the Gaussian minimum frequency shift keying waveform, and determine the number of code elements based on the Gaussian filter normalized bandwidth; the number of code elements is the number of code elements on the left and right sides of the target code element when inter-code crosstalk is performed on the target code element in the original information sequence;

[0013] Determine the length of the reference sequence and the number of spread spectrum sequences using the number of code elements;

[0014] Determine the reference sequence based on the length of the reference sequence and the original information sequence of the communication signal;

[0015] The spreading sequence is determined according to the spreading factor and the number of spreading sequences.

[0016] Optionally, determining the spreading sequence by using the spreading factor and the number of spreading sequences includes:

[0017] The spreading sequence is determined by the spreading factor, the number of spreading sequences, and a Gold code generated based on a cyclic shift XOR of two M sequences.

[0018] Optionally, the performing shift mapping on the original information sequence of the communication signal according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence includes:

[0019] The original information sequence is shifted based on the reference sequence and the preset bit to determine a shifted sequence, and the shifted sequence is mapped according to the spread spectrum sequence mapping table to obtain the spread spectrum sequence.

[0020] In a second aspect, the present application discloses a communication signal processing method, which is applied to a receiving end, comprising:

[0021] Determine a target bit differential phase value corresponding to the spread spectrum sequence under a Gaussian minimum frequency shift keying waveform, construct a differential phase table according to the target bit differential phase value, and use the differential phase table to determine a differential phase array corresponding to the spread spectrum sequence of a target length;

[0022] Receive the modulated signal sent by the transmitting end, perform target bit differential phase detection on the modulated signal, and determine the maximum likelihood path of the original information sequence state transition of the communication signal based on the corresponding differential phase detection value, the differential phase array and the maximum likelihood decoding algorithm;

[0023] Constructing a spread spectrum sequence mapping table based on the correspondence between the spread spectrum sequence and the reference sequence, mapping the maximum likelihood path to the reference sequence according to the correspondence between the spread spectrum sequence mapping table and the differential phase table to obtain the original information sequence, and completing demodulation and despreading of the communication signal;

[0024] The spread spectrum sequence and the reference sequence are both sequences determined based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of the communication signal.

[0025] Optionally, the determining the maximum likelihood path of the state transition of the original information sequence of the communication signal based on the corresponding differential phase detection value, the differential phase array and the maximum likelihood decoding algorithm includes:

[0026] The branch path metric of the state transition of the original information sequence is calculated using a preset branch path metric calculation formula, the differential phase detection value, and the differential phase array; the preset branch path metric calculation formula is:

[0027] ;

[0028] in, For state S k Transition to state S k+1 The branch path metric of ; N is the length of the differential phase array; is the differential phase detection value; is the differential phase array; is a constant;

[0029] Determine the total path metric of the original information sequence state transfer according to the branch path metric;

[0030] The maximum likelihood path of the state transition of the original information sequence is determined based on the branch path metric, the total path metric and the maximum likelihood decoding algorithm.

[0031] Optionally, determining the total path metric of the original information sequence state transition according to the branch path metric includes:

[0032] The total path metric of the original information sequence state transition is calculated based on the preset total path metric calculation formula and the branch path metric; the preset total path metric calculation formula is:

[0033] ;

[0034] in, For state S k Transition to state S k+1 The branch path metric of is the total path metric for the state transition of the original information sequence; For state S k The corresponding path metric.

[0035] Optionally, the determining the maximum likelihood path of the state transition of the original information sequence based on the branch path metric, the total path metric, and a maximum likelihood decoding algorithm includes:

[0036] Performing a forward state transfer on the original information sequence based on the branch path metric and the total path metric, and saving a target path with the smallest total path metric when multiple branch paths arrive at the same state node during the forward state transfer process;

[0037] When the demodulation length is equal to the backtracking length set according to the maximum likelihood decoding algorithm, the minimum total path metric is determined, and the state corresponding to the minimum total path metric is backtracked to obtain the maximum likelihood path; the minimum total path metric is the minimum total path metric among the total path metrics of each target path.

[0038] In a third aspect, the present application discloses a communication signal processing method, which is applied to a transmitting end, comprising:

[0039] A sequence determination module, used to determine a reference sequence and a spread spectrum sequence based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of a communication signal;

[0040] A mapping table construction module, used to correspond the spread spectrum sequence to the reference sequence, and construct a spread spectrum sequence mapping table according to the corresponding correspondence;

[0041] The modulated signal sending module is used to shift and map the original information sequence of the communication signal according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, modulate the spread spectrum sequence, and send the corresponding modulated signal to the receiving end so that the receiving end can demodulate and despread the modulated signal.

[0042] In a fourth aspect, the present application discloses a communication signal processing method, which is applied to a receiving end, comprising:

[0043] A phase table and array determination module, used to determine a target bit differential phase value corresponding to a spread spectrum sequence under a Gaussian minimum frequency shift keying waveform, construct a differential phase table according to the target bit differential phase value, and use the differential phase table to determine a differential phase array corresponding to a spread spectrum sequence of a target length;

[0044] A maximum likelihood path determination module is used to receive a modulated signal sent by a transmitter, perform target bit differential phase detection on the modulated signal, and determine a maximum likelihood path for state transfer of an original information sequence of a communication signal based on a corresponding differential phase detection value, the differential phase array, and a maximum likelihood decoding algorithm;

[0045] A demodulation and despreading module, configured to construct a spread spectrum sequence mapping table based on the correspondence between the spread spectrum sequence and the reference sequence, and map the maximum likelihood path to the reference sequence according to the correspondence between the spread spectrum sequence mapping table and the differential phase table to obtain the original information sequence, thereby completing demodulation and despreading of the communication signal;

[0046] The spread spectrum sequence and the reference sequence are both sequences determined based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of the communication signal.

[0047] In a fifth aspect, the present application discloses an electronic device, including:

[0048] Memory, used to store computer programs;

[0049] The processor is used to execute the computer program to implement the communication signal processing method as described above.

[0050] In a sixth aspect, the present application discloses a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the communication signal processing method as described above.

[0051] The transmitting end of the present application first determines the reference sequence and the spread spectrum sequence based on the waveform parameters and spread spectrum factor of the Gaussian minimum frequency shift keying waveform of the communication signal; the spread spectrum sequence is matched with the reference sequence, and a spread spectrum sequence mapping table is constructed according to the corresponding correspondence; the original information sequence of the communication signal is shift-mapped according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, the spread spectrum sequence is modulated, and the corresponding modulated signal is sent to the receiving end so that the receiving end can demodulate and despread the modulated signal. It can be seen that the present application proposes a shift mapping method for spread spectrum based on the state transfer process by constructing a time sequence state transfer, and sends the spread spectrum signal to the receiving end for demodulation and despreading. In this way, the present application can realize non-spread spectrum and different spread spectrum factors for transceiver communication, and can make more full use of the spread spectrum gain to ensure reliable communication under extremely low signal-to-noise ratio conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0053] Figure 1 A flow chart of a communication signal processing method disclosed in this application;

[0054] Figure 2 A schematic diagram of a spread spectrum sequence mapping disclosed in this application;

[0055] Figure 3 A schematic diagram of a process of shifted M-ary mapping spread spectrum disclosed in this application;

[0056] Figure 4 A flow chart of a communication signal processing method disclosed in this application;

[0057] Figure 5 This is a schematic diagram of an ideal differential phase diagram disclosed in this application;

[0058] Figure 6 A schematic diagram of a process of Viterbi joint demodulation, despreading and restoring the original information sequence at a receiving end disclosed in the present application;

[0059] Figure 7 A schematic diagram of the structure of a communication signal processing device disclosed in this application;

[0060] Figure 8 A schematic diagram of the structure of a communication signal processing device disclosed in this application;

[0061] Fig. 9 This is a structural diagram of an electronic device disclosed in this application. DETAILED DESCRIPTION

[0062] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0063] There are two main signal processing methods in the existing GMSK spread spectrum system: the first method directly chooses to adopt the processing of demodulation before despreading in the face of the difficulty of despreading before demodulation, and adds spread spectrum and despreading modules at both ends of the modulation and demodulation of the system. By correlating the local pseudo code sequence with the demodulated output, the original information sequence is determined. This method has a good knowledge foundation in spread spectrum and despreading methods, low design and implementation complexity, and simple structure, which is easy to directly integrate into the architecture of the transceiver system. However, since this method demodulates the received signal first, the signal-to-noise ratio of its input is not improved. The demodulation error at a low signal-to-noise ratio limits the efficiency of the back-end despreading module, which is not conducive to the utilization of spread spectrum gain. The second method adopts a processing mode of joint demodulation and despreading, adds a spread spectrum module to the modulation front end of the system, and combines the demodulation and despreading modules of the receiving end by combining the relevant methods into the demodulation algorithm. The received signal can directly determine the original information sequence through this module. This method requires a specific algorithm design for the joint demodulation and despreading method and even the spread spectrum method. Compared with the first method, its design and implementation complexity is higher, and it usually requires targeted modifications to the framework of the transceiver system. However, due to the combination of the demodulation and despreading modules, its signal-to-noise ratio loss is smaller, the error transmission effect is less obvious, and at the same time, the loss of spread spectrum gain is smaller. In order to solve the above technical problems, the present application discloses a communication signal processing method, device, equipment and storage medium, which can make more full use of the spread spectrum gain to ensure reliable communication under extremely low signal-to-noise ratio conditions.

[0064] See also Figure 1 As shown, an embodiment of the present invention discloses a communication signal processing method, which is applied to a transmitting end and includes:

[0065] Step S11, determining a reference sequence and a spreading sequence based on waveform parameters and a spreading factor of a Gaussian minimum shift keying waveform of a communication signal.

[0066] In this embodiment, the normalized bandwidth of the Gaussian filter of the Gaussian minimum shift keying waveform of the communication signal is first determined, and the number of code elements is determined based on the normalized bandwidth of the Gaussian filter; the number of code elements is the number of code elements on the left and right sides of the target code element when the target code element in the original information sequence is subjected to inter-code interference; the length of the reference sequence of the communication signal and the number of spread spectrum sequences are determined by the number of code elements; the reference sequence is determined based on the length of the reference sequence and the original information sequence of the communication signal; the spread spectrum sequence is determined by the spread spectrum factor and the number of spread spectrum sequences. In a specific embodiment, the normalized bandwidth of the Gaussian filter of the GMSK waveform is first set to B t T, and the inter-symbol crosstalk suffered by the current symbol is caused by the L symbols on the left and right, and its value is determined by B t T determines the spreading factor N. tAfter determining the value of L, let M = 2L + 2 as the length of the reference sequence before mapping, and the number of spreading sequences is 2 M The spreading sequence is determined by the spreading factor, the number of spreading sequences, and the N-bit Gold code generated by the cyclic shift XOR of two M sequences.

[0067] Step S12: Match the spread spectrum sequence with the reference sequence, and construct a spread spectrum sequence mapping table according to the corresponding correspondence.

[0068] In this embodiment, after determining the reference sequence and the spreading sequence, a spreading sequence mapping table is constructed by matching the spreading sequence with the reference sequence one by one. t Take T=0.5 and N=32 as an example. At this time, L=1 and M=4. Then, two 32-bit M sequences are used to generate 16 Gold codes through cyclic shift XOR. The reference sequence and the spread spectrum sequence C i The mapping relationship is as follows Figure 2 shown.

[0069] Step S13, shift mapping the original information sequence of the communication signal according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, modulate the spread spectrum sequence, and send the corresponding modulated signal to the receiving end so that the receiving end can demodulate and despread the modulated signal.

[0070] In this embodiment, the transmitting end performs shift M-ary mapping spread spectrum, shifts the original information sequence based on the reference sequence and the preset bit, determines the shifted sequence, and maps the shifted sequence according to the spread spectrum sequence mapping table to obtain the spread spectrum sequence. Specifically, assuming that the original information sequence of the communication signal is ; , define the state , then in the decision of the kth codeword, state S k Transition to state S k+1 The sequences involved are ,Right now The decision is associated with the first 2L+2 codewords, which corresponds to the reference sequence length M. For the codewords in the original information sequence The spread spectrum mapping relationship is: ; is a spreading sequence of length N, with the sequence As a benchmark, every time the bit is shifted by 1 bit, an M-ary mapping spread spectrum is performed.

[0071] In a specific embodiment, Figure 3 As shown in B tT=0.5 (L=1, M=4), the original information sequence length is two bytes, N=32 as an example. The initial reference sequence is set to , the corresponding state transition is , as the original information sequence flows in, the reference sequence is continuously shifted by 1 bit and the state is continuously transferred. At each code element moment, the shifted reference sequence is mapped according to the spread spectrum sequence mapping table to obtain the spread spectrum sequence. Finally, the spread spectrum sequence is modulated, and the corresponding modulated signal is sent to the receiving end so that the receiving end can demodulate and despread the modulated signal. So far, this application uses the inherent inter-code interference characteristics introduced by the Gaussian filter for the differential phase of the signal to construct a state transfer in time sequence, and proposes a spread spectrum system of shifted M-element mapping based on the state transfer process, which realizes the spread spectrum modulation of the communication signal, and realizes the combination of advantageous waveform system and spread spectrum technology in communication scenarios such as deep space tracking and control and missile-borne data links.

[0072] In summary, the transmitting end of the present application first determines the reference sequence and the spread spectrum sequence based on the waveform parameters and spread spectrum factor of the Gaussian minimum frequency shift keying waveform of the communication signal; the spread spectrum sequence is matched with the reference sequence, and a spread spectrum sequence mapping table is constructed according to the corresponding correspondence; the original information sequence of the communication signal is shift-mapped according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, the spread spectrum sequence is modulated, and the corresponding modulated signal is sent to the receiving end so that the receiving end demodulates and despreads the modulated signal. It can be seen that the present application proposes a shift mapping method for spread spectrum based on the state transfer process by constructing a time sequence state transfer, and sends the spread spectrum signal to the receiving end for demodulation and despreading. In this way, the present application can realize non-spread spectrum and different spreading factors of transceiver communication, and can make more full use of the spread spectrum gain to ensure reliable communication under extremely low signal-to-noise ratio conditions.

[0073] See also Figure 4 As shown, an embodiment of the present invention discloses a communication signal processing method, which is applied to a receiving end and includes:

[0074] Step S21, determine the target bit differential phase value corresponding to the spread spectrum sequence under the Gaussian minimum frequency shift keying waveform, construct a differential phase table according to the target bit differential phase value, and use the differential phase table to determine the differential phase array corresponding to the spread spectrum sequence of the target length.

[0075] In this embodiment, based on the previous embodiment, it can be known that the transmitting end of the present application utilizes the inherent inter-code interference characteristics introduced by the Gaussian filter for the signal differential phase to construct a timing state transition, and proposes a spread spectrum system of shifted M-ary mapping based on the state transition process, thereby realizing spread spectrum modulation of the communication signal, and sending the modulated signal after spread spectrum modulation to the receiving end.

[0076] First, calculate the 2-bit ideal differential phase value corresponding to the spread spectrum sequence under the GMSK waveform and construct the ideal differential phase table at the receiving end. t Take T=0.5 and N=32 as an example; the corresponding ideal differential phase is calculated from the code element information of the spread spectrum sequence, in radians, with a value range of ; The corresponding relationship between the spread spectrum sequence and the ideal differential phase is as follows Figure 5 As shown. Then, the differential phase table can be used to determine the differential phase array corresponding to the spread spectrum sequence of the target length, that is, under the shift M-ary mapping spread spectrum system, a state transition of the pre-spread spectrum sequence is mapped to a spread spectrum sequence C of length N. i , and the corresponding ideal differential phase array with length N , which matches the L-time delayed differential phase of the received signal.

[0077] Step S22, receiving the modulated signal sent by the transmitting end, performing target bit differential phase detection on the modulated signal, and determining the maximum likelihood path of the state transition of the original information sequence of the communication signal based on the corresponding differential phase detection value, the differential phase array and the maximum likelihood decoding algorithm.

[0078] In this embodiment, after receiving the modulated signal sent by the transmitting end, the modulated signal is subjected to target bit differential phase detection, that is, the 2-bit differential phase detection value of the received signal with a length of N is determined. , and then use the preset branch path metric calculation formula, differential phase detection value and differential phase array to calculate the branch path metric of the original information sequence state transition; the preset branch path metric calculation formula is:

[0079] ;

[0080] in, For state S k Transition to state S k+1 The branch path metric of ; N is the length of the differential phase array; is the differential phase detection value; is a differential phase array; is a constant.

[0081] Then, the total path metric of the original information sequence state transition is calculated based on the preset total path metric calculation formula and the branch path metric; the preset total path metric calculation formula is:

[0082] ;

[0083] in, For state S k Transition to state Sk+1 The branch path metric of is the total path metric for the state transition of the original information sequence; For state S k The corresponding path metric.

[0084] Finally, the original information sequence is forwarded to a state transfer based on the branch path metric and the total path metric. During the forward state transfer, the target path with the smallest total path metric is saved when multiple branch paths arrive at the same state node. When the demodulation length is equal to the backtracking length set according to the maximum likelihood decoding algorithm, the minimum total path metric is determined, and the state corresponding to the minimum total path metric is backtracked to obtain the maximum likelihood path. The minimum total path metric is the minimum total path metric among the total path metrics of each target path.

[0085] In a specific embodiment, Figure 6 As shown, the 2-bit differential phase detection value of the received signal with a length of N is The likelihood of the difference with the differential phase array is summed as the branch path metric of this state transition, and the forward state transition is performed by calculating the branch path metric and the total path metric. In other words, after the 2-bit differential phase detection value is delayed L times, the forward state transition process is entered. Based on the maximum likelihood criterion, when multiple branch paths reach the same state node, the path with the smallest total path metric is retained and the remaining paths are deleted. When the demodulation length reaches the backtracking length set by Viterbi, the minimum value in the final total path metric is selected, and the corresponding state is backtracked to obtain the maximum likelihood path.

[0086] Step S23: construct a spread spectrum sequence mapping table based on the correspondence between the spread spectrum sequence and the reference sequence, and map the maximum likelihood path to the reference sequence according to the correspondence between the spread spectrum sequence mapping table and the differential phase table to obtain the original information sequence, thereby completing the demodulation and despreading of the communication signal.

[0087] In this embodiment, the minimum value in the final total path metric is selected, and the corresponding state is traced back to obtain the maximum likelihood path. Then, the maximum likelihood ideal differential phase in time sequence can be obtained by tracing back the state transition process of the maximum likelihood path; finally, the state transition process at the symbol level is restored through the mapping relationship between the ideal differential phase and the spread spectrum sequence and the reference sequence, and the original information sequence is determined to complete the joint demodulation and despreading. That is, according to the corresponding relationship between the spread spectrum sequence mapping table and the ideal differential phase table, the state transition of the maximum likelihood path is mapped back to the sequence ,Pick The value is used as the decision of the kth code element interval, and the original information sequence is obtained. In this way, the present application supports non-spread spectrum and receiving and transmitting communications with different spreading factors, and the best non-coherent processing performance can be obtained based on the maximum likelihood criterion. Compared with the processing mode of demodulation before despreading, the spread spectrum gain can be more fully utilized to ensure reliable communication under extremely low signal-to-noise ratio conditions. It should be noted that the spread spectrum sequence and the reference sequence are both sequences determined by the waveform parameters and the spreading factor of the Gaussian minimum shift keying waveform of the communication signal. The specific determination process of the spread spectrum sequence and the reference sequence can refer to the previous embodiment, which will not be repeated here.

[0088] In summary, the receiving end of the present application first determines the target bit differential phase value corresponding to the spread spectrum sequence under the Gaussian minimum frequency shift keying waveform, constructs a differential phase table according to the target bit differential phase value, and uses the differential phase table to determine the differential phase array corresponding to the spread spectrum sequence of the target length; then receives the modulated signal sent by the transmitting end, performs target bit differential phase detection on the modulated signal, and determines the maximum likelihood path of the state transition of the original information sequence of the communication signal based on the corresponding differential phase detection value, the differential phase array and the maximum likelihood decoding algorithm; finally, constructs a spread spectrum sequence mapping table based on the correspondence between the spread spectrum sequence and the reference sequence, maps the maximum likelihood path to the reference sequence according to the correspondence between the spread spectrum sequence mapping table and the differential phase table, so as to obtain the original information sequence, and complete the demodulation and despreading of the communication signal. It can be seen that the present application performs the maximum likelihood decoding algorithm for joint demodulation and despreading after obtaining the modulated signal sent by the transmitting end. In this way, it can support non-spread spectrum and receiving and transmitting communications with different spreading factors, and can obtain the best non-coherent processing performance based on the maximum likelihood criterion. Compared with the processing mode of demodulating first and then despreading, it can make more full use of the spreading gain to ensure reliable communication under extremely low signal-to-noise ratio conditions.

[0089] See also Figure 7 As shown, an embodiment of the present invention discloses a communication signal processing device, which is applied to a transmitting end and includes:

[0090] A sequence determination module 11, used to determine a reference sequence and a spread spectrum sequence based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of a communication signal;

[0091] A mapping table building module 12, used to correspond the spread spectrum sequence to the reference sequence, and build a spread spectrum sequence mapping table according to the corresponding correspondence;

[0092] The modulated signal sending module 13 is used to shift and map the original information sequence of the communication signal according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, modulate the spread spectrum sequence, and send the corresponding modulated signal to the receiving end so that the receiving end can demodulate and despread the modulated signal.

[0093] The transmitting end of the present application first determines the reference sequence and the spread spectrum sequence based on the waveform parameters and spread spectrum factor of the Gaussian minimum frequency shift keying waveform of the communication signal; the spread spectrum sequence is matched with the reference sequence, and a spread spectrum sequence mapping table is constructed according to the corresponding correspondence; the original information sequence of the communication signal is shift-mapped according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, the spread spectrum sequence is modulated, and the corresponding modulated signal is sent to the receiving end so that the receiving end can demodulate and despread the modulated signal. It can be seen that the present application proposes a shift mapping method for spread spectrum based on the state transfer process by constructing a time sequence state transfer, and sends the spread spectrum signal to the receiving end for demodulation and despreading. In this way, the present application can realize non-spread spectrum and different spread spectrum factors for transceiver communication, and can make more full use of the spread spectrum gain to ensure reliable communication under extremely low signal-to-noise ratio conditions.

[0094] In some specific embodiments, the sequence determination module 11 may specifically include:

[0095] A code element number determination unit, used to determine the Gaussian filter normalized bandwidth of the Gaussian minimum frequency shift keying waveform, and determine the code element number based on the Gaussian filter normalized bandwidth; the code element number is the number of code elements on the left and right sides of the target code element when inter-code crosstalk is performed on the target code element in the original information sequence;

[0096] A length and number determination unit, configured to determine the length of the reference sequence and the number of spread spectrum sequences using the number of code elements;

[0097] A reference sequence determining unit, configured to determine the reference sequence based on the length of the reference sequence and an original information sequence of the communication signal;

[0098] The spreading sequence determining unit is configured to determine the spreading sequence according to the spreading factor and the number of spreading sequences.

[0099] In some specific embodiments, the spreading sequence determining unit may specifically include:

[0100] The spreading sequence determination subunit is used to determine the spreading sequence according to the spreading factor, the number of spreading sequences and a Gold code generated based on a cyclic shift XOR of two M sequences.

[0101] In some specific embodiments, the modulated signal sending module 13 may specifically include:

[0102] The spreading sequence acquisition unit is used to shift the original information sequence based on the reference sequence and the preset bit to determine a shifted sequence, and map the shifted sequence according to the spreading sequence mapping table to obtain the spread sequence.

[0103] See also Figure 8 As shown, an embodiment of the present invention discloses a communication signal processing device, which is applied to a receiving end, including:

[0104] The phase table and array determination module 21 is used to determine the target bit differential phase value corresponding to the spread spectrum sequence under the Gaussian minimum frequency shift keying waveform, construct a differential phase table according to the target bit differential phase value, and use the differential phase table to determine the differential phase array corresponding to the spread spectrum sequence of the target length;

[0105] The maximum likelihood path determination module 22 is used to receive the modulated signal sent by the transmitter, perform target bit differential phase detection on the modulated signal, and determine the maximum likelihood path of the original information sequence state transfer of the communication signal based on the corresponding differential phase detection value, the differential phase array and the maximum likelihood decoding algorithm;

[0106] The demodulation and despreading module 23 is used to construct a spread spectrum sequence mapping table based on the correspondence between the spread spectrum sequence and the reference sequence, and map the maximum likelihood path to the reference sequence according to the correspondence between the spread spectrum sequence mapping table and the differential phase table to obtain the original information sequence, thereby completing the demodulation and despreading of the communication signal;

[0107] The spread spectrum sequence and the reference sequence are both sequences determined based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of the communication signal.

[0108] In some specific embodiments, the maximum likelihood path determination module 22 may specifically include:

[0109] A branch path metric calculation unit is used to calculate the branch path metric of the original information sequence state transition using a preset branch path metric calculation formula, the differential phase detection value, and the differential phase array; the preset branch path metric calculation formula is:

[0110] ;

[0111] in, For state S k Transition to state S k+1The branch path metric of ; N is the length of the differential phase array; is the differential phase detection value; is the differential phase array; is a constant;

[0112] A total path metric determination unit, used to determine the total path metric of the original information sequence state transfer according to the branch path metric;

[0113] The maximum likelihood path determination unit is used to determine the maximum likelihood path of the state transition of the original information sequence based on the branch path metric, the total path metric and the maximum likelihood decoding algorithm.

[0114] In some specific embodiments, the total path metric determination unit may specifically include:

[0115] The total path metric calculation subunit is used to calculate the total path metric of the original information sequence state transition based on a preset total path metric calculation formula and the branch path metric; the preset total path metric calculation formula is:

[0116] ;

[0117] in, For state S k Transition to state S k+1 The branch path metric of is the total path metric for the state transition of the original information sequence; For state S k The corresponding path metric.

[0118] In some specific embodiments, the maximum likelihood path determination unit may specifically include:

[0119] a target path saving subunit, configured to perform a forward state transfer on the original information sequence based on the branch path metric and the total path metric, and save the target path with the smallest total path metric when multiple branch paths arrive at the same state node during the forward state transfer process;

[0120] The maximum likelihood path determination subunit is used to determine the minimum total path metric when the demodulation length is equal to the backtracking length set according to the maximum likelihood decoding algorithm, and backtrack the state corresponding to the minimum total path metric to obtain the maximum likelihood path; the minimum total path metric is the minimum total path metric among the total path metrics of each target path.

[0121] Furthermore, the present application also discloses an electronic device. Fig. 9This is a structural diagram of an electronic device 30 according to an exemplary embodiment. The content in the diagram cannot be regarded as any limitation on the scope of use of the present application.

[0122] Fig. 9 The present invention provides a schematic diagram of the structure of an electronic device 30 provided in an embodiment of the present application. The electronic device 30 may specifically include: at least one processor 31, at least one memory 32, a power supply 33, a communication interface 34, an input / output interface 35, and a communication bus 36. The memory 32 is used to store a computer program, which is loaded and executed by the processor 31 to implement the relevant steps in the communication signal processing method disclosed in any of the aforementioned embodiments. In addition, the electronic device 30 in this embodiment may specifically be an electronic computer.

[0123] In this embodiment, the power supply 33 is used to provide working voltage for each hardware device on the electronic device 30; the communication interface 34 can create a data transmission channel between the electronic device 30 and the external device, and the communication protocol it follows is any communication protocol that can be applied to the technical solution of the present application, and is not specifically limited here; the input and output interface 35 is used to obtain external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs and is not specifically limited here.

[0124] In addition, the memory 32 as a carrier for resource storage may be a read-only memory, a random access memory, a disk or an optical disk, etc. The resources stored thereon may include an operating system 321, a computer program 322, etc., and the storage method may be temporary storage or permanent storage.

[0125] The operating system 321 is used to manage and control the hardware devices and computer programs 322 on the electronic device 30, which can be Windows Server, Netware, Unix, Linux, etc. In addition to including a computer program that can be used to complete the communication signal processing method performed by the electronic device 30 disclosed in any of the aforementioned embodiments, the computer program 322 can further include a computer program that can be used to complete other specific tasks.

[0126] Furthermore, the present application also discloses a computer-readable storage medium for storing a computer program; wherein the computer program, when executed by a processor, implements the communication signal processing method disclosed above. For the specific steps of the method, reference may be made to the corresponding contents disclosed in the above embodiments, and no further description will be given here.

[0127] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0128] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0129] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0130] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, 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 other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0131] The technical solution provided by the present application is introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technicians in this field, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A communication signal processing method, characterized in that: Applied to the transmitter, including: Determine a reference sequence and a spread spectrum sequence based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of a communication signal; Matching the spread spectrum sequence with the reference sequence, and constructing a spread spectrum sequence mapping table according to the corresponding correspondence; Shift-map the original information sequence of the communication signal according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, modulate the spread spectrum sequence, and send the corresponding modulated signal to the receiving end so that the receiving end demodulates and despreads the modulated signal; The method of determining a reference sequence and a spread spectrum sequence based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of a communication signal comprises: Determine the Gaussian filter normalized bandwidth of the Gaussian minimum frequency shift keying waveform, and determine the number of code elements based on the Gaussian filter normalized bandwidth; the number of code elements is the number of code elements on the left and right sides of the target code element when inter-code crosstalk is performed on the target code element in the original information sequence; Determine the length of the reference sequence and the number of spread spectrum sequences using the number of code elements; Determine the reference sequence based on the length of the reference sequence and the original information sequence of the communication signal; The spreading sequence is determined according to the spreading factor and the number of spreading sequences.

2. The communication signal processing method according to claim 1, characterized in that: The determining the spreading sequence by using the spreading factor and the number of spreading sequences comprises: The spreading sequence is determined by the spreading factor, the number of spreading sequences, and a Gold code generated based on a cyclic shift XOR of two M sequences.

3. The communication signal processing method according to claim 1 or 2, characterized in that: The performing shift mapping on the original information sequence of the communication signal according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence includes: The original information sequence is shifted based on the reference sequence and the preset bit to determine a shifted sequence, and the shifted sequence is mapped according to the spread spectrum sequence mapping table to obtain the spread spectrum sequence.

4. A communication signal processing method, characterized in that: Applied to the receiving end, including: Determine a target bit differential phase value corresponding to the spread spectrum sequence under a Gaussian minimum frequency shift keying waveform, construct a differential phase table according to the target bit differential phase value, and use the differential phase table to determine a differential phase array corresponding to the spread spectrum sequence of a target length; Receive the modulated signal sent by the transmitting end, perform target bit differential phase detection on the modulated signal, and determine the maximum likelihood path of the original information sequence state transition of the communication signal based on the corresponding differential phase detection value, the differential phase array and the maximum likelihood decoding algorithm; Constructing a spread spectrum sequence mapping table based on the correspondence between the spread spectrum sequence and the reference sequence, mapping the maximum likelihood path to the reference sequence according to the correspondence between the spread spectrum sequence mapping table and the differential phase table to obtain the original information sequence, and completing demodulation and despreading of the communication signal; The spread spectrum sequence and the reference sequence are both sequences determined based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of the communication signal.

5. The communication signal processing method according to claim 4, characterized in that: The method of determining the maximum likelihood path of the state transition of the original information sequence of the communication signal based on the corresponding differential phase detection value, the differential phase array and the maximum likelihood decoding algorithm comprises: The branch path metric of the state transition of the original information sequence is calculated using a preset branch path metric calculation formula, the differential phase detection value, and the differential phase array; the preset branch path metric calculation formula is: ； in, For state S k Transition to state S k+1 The branch path metric of ; N is the length of the differential phase array; is the differential phase detection value; is the differential phase array; is a constant; Determine the total path metric of the original information sequence state transfer according to the branch path metric; The maximum likelihood path of the state transition of the original information sequence is determined based on the branch path metric, the total path metric and the maximum likelihood decoding algorithm.

6. The communication signal processing method according to claim 5, characterized in that: The determining the total path metric of the original information sequence state transition according to the branch path metric comprises: The total path metric of the original information sequence state transition is calculated based on the preset total path metric calculation formula and the branch path metric; the preset total path metric calculation formula is: ； in, For state S k Transition to state S k+1 The branch path metric of is the total path metric for the state transition of the original information sequence; For state S k The corresponding path metric.

7. The communication signal processing method according to claim 5, characterized in that: The determining the maximum likelihood path of the state transition of the original information sequence based on the branch path metric, the total path metric and the maximum likelihood decoding algorithm comprises: Performing a forward state transfer on the original information sequence based on the branch path metric and the total path metric, and saving a target path with the smallest total path metric when multiple branch paths arrive at the same state node during the forward state transfer process; When the demodulation length is equal to the backtracking length set according to the maximum likelihood decoding algorithm, the minimum total path metric is determined, and the state corresponding to the minimum total path metric is backtracked to obtain the maximum likelihood path; the minimum total path metric is the minimum total path metric among the total path metrics of each target path.

8. A communication signal processing device, characterized in that: Applied to the transmitter, including: A sequence determination module, used to determine a reference sequence and a spread spectrum sequence based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of a communication signal; A mapping table construction module, used to correspond the spread spectrum sequence to the reference sequence, and construct a spread spectrum sequence mapping table according to the corresponding correspondence; A modulated signal sending module is used to shift and map the original information sequence of the communication signal according to the reference sequence and the spread spectrum sequence mapping table to obtain a spread spectrum sequence, modulate the spread spectrum sequence, and send the corresponding modulated signal to the receiving end so that the receiving end can demodulate and despread the modulated signal; The sequence determination module comprises: A code element number determination unit, used to determine the Gaussian filter normalized bandwidth of the Gaussian minimum frequency shift keying waveform, and determine the code element number based on the Gaussian filter normalized bandwidth; the code element number is the number of code elements on the left and right sides of the target code element when inter-code crosstalk is performed on the target code element in the original information sequence; A length and number determination unit, configured to determine the length of the reference sequence and the number of spread spectrum sequences using the number of code elements; A reference sequence determining unit, configured to determine the reference sequence based on the length of the reference sequence and an original information sequence of the communication signal; The spreading sequence determining unit is configured to determine the spreading sequence according to the spreading factor and the number of spreading sequences.

9. A communication signal processing device, characterized in that: Applied to the receiving end, including: A phase table and array determination module, used to determine a target bit differential phase value corresponding to a spread spectrum sequence under a Gaussian minimum frequency shift keying waveform, construct a differential phase table according to the target bit differential phase value, and use the differential phase table to determine a differential phase array corresponding to a spread spectrum sequence of a target length; A maximum likelihood path determination module is used to receive a modulated signal sent by a transmitter, perform target bit differential phase detection on the modulated signal, and determine a maximum likelihood path for state transfer of an original information sequence of a communication signal based on a corresponding differential phase detection value, the differential phase array, and a maximum likelihood decoding algorithm; A demodulation and despreading module, configured to construct a spread spectrum sequence mapping table based on the correspondence between the spread spectrum sequence and the reference sequence, and map the maximum likelihood path to the reference sequence according to the correspondence between the spread spectrum sequence mapping table and the differential phase table to obtain the original information sequence, thereby completing demodulation and despreading of the communication signal; The spread spectrum sequence and the reference sequence are both sequences determined based on waveform parameters and a spread spectrum factor of a Gaussian minimum shift keying waveform of the communication signal.

10. An electronic device, characterized in that: include: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the communication signal processing method according to any one of claims 1 to 7.

11. A computer-readable storage medium, characterized in that: Used to store a computer program, wherein when the computer program is executed by a processor, the communication signal processing method according to any one of claims 1 to 7 is implemented.

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