An integrated transmission method for radar communication based on USRP

Abstract

The present invention discloses a radar communication integrated transmission method based on USRP, and relates to the field of signal processing. The present invention realizes the transmission and receiving process of radar communication integration based on USRP signal transmission module and USRP signal receiving module; when transmitting, first start the USRP transmission session, then configure the transmission parameters, load the radar communication integrated waveform, and use the USRP transmission waveform; when receiving, start the USRP reception session, configure the reception parameters, use the USRP reception waveform, if it is communication reception, perform communication reception processing and output the constellation diagram and communication data, if it is radar reception, perform radar reception processing and output the detection parameters and detection results. The present invention can be used for target perception detection and communication, and can add radar detection function to the system without losing communication performance.

Description

Technical Field

[0001] The present invention relates to the field of signal processing, and in particular to a radar communication integrated transmission method based on USRP. Background Art

[0002] With the continuous development of wireless communication and radar technology, spectrum resources are becoming more and more scarce. In order to avoid excessive occupation and waste of spectrum resources, there is an urgent need for a way to efficiently use spectrum. In addition, the development of digital signal processing technology, antenna technology and radio frequency technology has made it possible to integrate multiple functions on the same hardware platform through advanced signal processing algorithms.

[0003] Radar communication integration technology combines radar functions with communication functions, and this technology has obvious advantages. On the one hand, it can reduce the size, weight and power consumption of the system because there is no need to configure independent complete equipment for radar and communication. On the other hand, it can effectively improve the spectrum utilization rate. By reasonably designing the signal waveform, the spectrum resources can serve both radar and communication functions. For example, in an intelligent transportation system, the vehicle's radar communication integration equipment can detect surrounding vehicles and obstacles while exchanging information such as road conditions with the traffic management system or other vehicles. Summary of the invention

[0004] In view of this, the present invention proposes a radar communication integrated transmission method based on USRP. The method can be used for target perception detection and communication, and can add radar detection function to the system without losing communication performance.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A radar communication integrated transmission method based on USRP, based on USRP signal transmitting module and USRP signal receiving module to realize the integrated transmission and receiving process of radar communication, specifically, the integrated transmission process of radar communication includes the following steps:

[0007] Step a1, set the device ID of the USRP signal transmission module and start the USRP transmission session;

[0008] Step a2, configure the transmission parameters of the USRP signal transmission module, set the activation channel ID, data type, clock and frequency source, IQ rate, carrier frequency, transmission gain and antenna selection;

[0009] Step a3, using a built-in MATLAB script to generate a radar communication integrated baseband waveform signal, outputting the real part and the imaginary part of the radar communication integrated baseband waveform signal respectively, and displaying the waveform and spectrum of the radar communication integrated baseband waveform signal;

[0010] Step a4, setting the transmission mode, combining the real part and the imaginary part of the radar communication integrated baseband waveform signal into one path and writing it into the USRP signal transmission module to wait for transmission;

[0011] Step a5, after the transmission is completed, close the USRP transmission session to complete the transmission of radar communication integration;

[0012] The radar communication integrated receiving process comprises the following steps:

[0013] Step 1, set the device ID of the USRP signal receiving module and start the USRP receiving session;

[0014] Step 2: Configure the receiving parameters of the USRP signal receiving module, set the activation channel ID, data type, clock and frequency source, IQ rate, carrier frequency, receiving gain, and antenna selection;

[0015] Step 3, enable USRP signal reception at the receiving end, and obtain the baseband receiving signal received by the USRP signal receiving module;

[0016] Step 4, select communication reception or radar reception, and input the baseband reception signal into the corresponding built-in MATLAB script for processing. If it is communication reception, communication reception processing is performed and the constellation diagram and communication data are output. If it is radar reception, radar reception processing is performed and detection parameters and detection results are output;

[0017] Step 5. Close the USRP receive session and exit the program.

[0018] Furthermore, the specific method of using the built-in MATLAB script to generate the radar communication integrated baseband waveform signal in step a3 is:

[0019] Step a301, for the generated binary bit stream communication data, based on The bit lengths are selected in sequence, where is the modulation order, is the number of data carriers; Bit length binary is recorded as binary bit stream communication data vector ;

[0020] Step a302, convert the binary bit stream communication data vector Perform constellation mapping and obtain a length of The vector after constellation mapping ;

[0021] Step a303, inserting scattered pilots and continuous pilot data according to the pilot pattern to obtain a length of Vector ;

[0022] Step a304, insert zero carrier, and obtain a length of Vector ;

[0023] Step a305, perform Point IFFT transformation to obtain OFDM baseband modulation signal ;

[0024] Step a306, insert a cyclic prefix to obtain a length of OFDM symbol vector ;

[0025] Step a307, OFDM symbols are combined into one frame, and a frame synchronization header is added to obtain the output radar communication integrated baseband waveform signal .

[0026] Furthermore, if it is communication reception in step 4, the specific method of performing communication reception processing and outputting the constellation diagram and communication data is:

[0027] Step b401, assume that the communication baseband receiving signal received by the USRP signal receiving module after passing through the channel is First, perform signal synchronization to obtain the accurate frame start position and obtain OFDM symbols ;

[0028] Step b402, remove the cyclic prefix and obtain a length of Baseband signal to be demodulated ;

[0029] Step b403, proceed Point FFT transformation to obtain OFDM baseband demodulated signal ;

[0030] Step b404, delete the zero carrier and obtain a length of Vector ;

[0031] Step b405, perform channel estimation based on the pilot pattern and obtain the channel response as ;

[0032] Step b406, perform equalization to obtain an equalized signal , which is calculated as:

[0033] ;

[0034] Step b407, delete the scattered pilot and continuous pilot data according to the pilot pattern, and obtain a length of communication signals And the corresponding constellation diagram;

[0035] Step b408, perform constellation demapping to obtain the received binary bit stream communication data .

[0036] Furthermore, if it is radar reception in step 4, the specific method of performing radar reception processing and outputting detection parameters and detection results is as follows:

[0037] Step c401, assume that the radar baseband receiving signal received by the USRP signal receiving module after passing through the channel is First, perform signal synchronization to obtain the accurate frame start position and obtain OFDM symbols ;

[0038] Step c402, remove the cyclic prefix and obtain a length of Baseband signal to be demodulated ;

[0039] Step c403, proceed Point FFT transformation to obtain OFDM baseband demodulated signal ;

[0040] Step c404, delete the zero carrier and obtain a length of Vector ;

[0041] Step c405, calculate the channel response matrix, first calculate the channel response of each symbol :

[0042] ;

[0043] Will The channel response matrix is ​​constructed by :

[0044] H r = [ h 1 , r , h 2 , r ,..., h N sym , r ] T ;

[0045] in 1× , indicating the column vector of The channel response of symbols, i=1,2,3,..., , represents the matrix transpose, represents a complex domain;

[0046] Step c406, perform two FFT transformations and one modulo operation on the channel response matrix to obtain the range-Doppler matrix :

[0047] D = abs ( [ F N sym ( F N c H r ) T ] T ) ;

[0048] in It means taking the modulus of each element in the matrix. and Respectively Point FFT Matrix and Point FFT matrix, represents the field of real numbers;

[0049] Step c407, calculating and displaying radar detection resolution parameters, wherein the radar detection resolution parameters include range resolution, maximum unambiguous range, speed resolution, and maximum unambiguous speed;

[0050] The distance resolution The calculation method is:

[0051] ;

[0052] in represents the speed of light, Indicates IQ rate;

[0053] Maximum unambiguous distance The calculation method is:

[0054] ;

[0055] Speed ​​resolution The calculation method is:

[0056] ;

[0057] in Indicates the carrier frequency;

[0058] Maximum unambiguous speed The calculation method is:

[0059] .

[0060] Due to the adoption of the above technical solution, the beneficial effects of the present invention compared with the prior art are:

[0061] 1. The present invention generates an integrated radar communication waveform based on an OFDM communication system, which can introduce detection and perception functions and improve system capabilities without reducing communication performance.

[0062] 2. The present invention builds a signal transmission and receiving system based on a software radio architecture, so that the system has the functions of dynamic parameter adjustment and later upgrading and transformation, thereby improving the flexibility of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 The present invention is a schematic diagram of the transmission process flow of radar communication integration of a radar communication integration transmission method based on USRP in an embodiment of the present invention.

[0064] Figure 2 for Figure 1 Schematic diagram of the radar communication integration waveform loaded in.

[0065] Figure 3 It is a flowchart of the radar communication integrated receiving process in an embodiment of the present invention.

[0066] Figure 4 for Figure 3 Schematic diagram of radar receiving and processing.

[0067] Figure 5 for Figure 3 Schematic diagram of communication reception processing.

[0068] Figure 6 It is a schematic diagram showing the transmission process interface of radar communication integration in an embodiment of the present invention.

[0069] Figure 7 The figure is a schematic diagram showing an interface for communication reception processing in an embodiment of the present invention.

[0070] Figure 8 This is a schematic diagram showing an interface for radar reception processing in an embodiment of the present invention. DETAILED DESCRIPTION

[0071] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0072] A radar communication integrated transmission method based on USRP, based on USRP signal transmitting module and USRP signal receiving module to realize the integrated transmission and receiving process of radar communication, specifically, Figure 1 As shown, the radar communication integrated transmission process includes the following steps:

[0073] Step a1, set the device ID of the USRP signal transmission module and start the USRP transmission session;

[0074] Specifically, in this embodiment, the device ID is RIO0;

[0075] Step a2, configure the transmission parameters of the USRP signal transmission module, set the activation channel ID, data type, clock and frequency source, IQ rate, carrier frequency, transmission gain and antenna selection;

[0076] Specifically, in this embodiment, the activated channel ID is 0, the data type is I16, the clock and frequency sources are both built-in, the IQ rate is 20MHz, the carrier frequency is 2GHz, the transmission gain is 0dB, and the antenna is TX1;

[0077] Step a3, use the built-in MATLAB script to generate the radar communication integrated baseband waveform signal, and output the real part and imaginary part of the radar communication integrated baseband waveform signal respectively, such as Figure 6 As shown, the waveform and spectrum of the radar communication integrated baseband waveform signal are displayed;

[0078] Step a4, setting the transmission mode, combining the real part and the imaginary part of the radar communication integrated baseband waveform signal into one path and writing it into the USRP signal transmission module to wait for transmission;

[0079] Specifically, in this embodiment, the transmission mode is a single-channel I16 mode;

[0080] Step a5, after the transmission is completed, close the USRP transmission session to complete the transmission of radar communication integration;

[0081] like Figure 3 As shown, the radar communication integrated receiving process includes the following steps:

[0082] Step 1, set the device ID of the USRP signal receiving module and start the USRP receiving session;

[0083] Specifically, in this embodiment, the device ID is RIO0;

[0084] Step 2: Configure the receiving parameters of the USRP signal receiving module, set the activation channel ID, data type, clock and frequency source, IQ rate, carrier frequency, receiving gain, and antenna selection;

[0085] Specifically, in this embodiment, the channel ID is set to 0, the data type is I16, the clock and frequency sources are both built-in, the IQ rate is 20MHz, the carrier frequency is 2GHz, the receiving gain is 20dB, and the antenna is RX1;

[0086] Step 3, enable USRP signal reception at the receiving end, and obtain the baseband receiving signal received by the USRP signal receiving module;

[0087] Step 4, select communication reception or radar reception, and input the baseband reception signal into the corresponding built-in MATLAB script for processing. If it is communication reception, communication reception processing is performed and the constellation diagram and communication data are output. If it is radar reception, radar reception processing is performed and detection parameters and detection results are output;

[0088] Step 5. Close the USRP receive session and exit the program.

[0089] Furthermore, if Figure 2 As shown in the figure, the specific method of using the built-in MATLAB script in step a3 to generate the radar communication integrated baseband waveform signal is:

[0090] Step a301, for the generated binary bit stream communication data, based on The bit lengths are selected in sequence, where is the modulation order, is the number of data carriers; Bit length binary is recorded as binary bit stream communication data vector ;

[0091] Specifically, in this embodiment, is the modulation order, i.e. QPSK modulation, is the number of data carriers;

[0092] Step a302, convert the binary bit stream communication data vector Perform constellation mapping and obtain a length of The vector after constellation mapping ;

[0093] Step a303, inserting scattered pilots and continuous pilot data according to the pilot pattern to obtain a length of Vector ;

[0094] Specifically, in this embodiment, the number of pilots is 193. ;

[0095] Step a304, insert zero carrier, and obtain a length of Vector ;

[0096] Specifically, in this embodiment, zero carriers are inserted at the first 172 and last 171 positions. ;

[0097] Step a305, perform Point IFFT transformation to obtain OFDM baseband modulation signal ;

[0098] Specifically, in this embodiment, a 2048-point IFFT transform is performed;

[0099] Step a306, insert a cyclic prefix to obtain a length of OFDM symbol vector ;

[0100] Specifically, in this embodiment, a cyclic prefix is ​​inserted with a length of 512; ;

[0101] Step a307, OFDM symbols are combined into one frame, and a frame synchronization header is added to obtain the output radar communication integrated baseband waveform signal .

[0102] Specifically, in this embodiment, ;

[0103] Furthermore, if Figure 5 As shown, in step 4, if it is communication reception, the specific method of performing communication reception processing and outputting the constellation diagram and communication data is:

[0104] Step b401, assume that the communication baseband receiving signal received by the USRP signal receiving module after passing through the channel is ,like Figure 7 As shown, first perform signal synchronization to obtain the accurate frame start position, and obtain OFDM symbols ;

[0105] Step b402, remove the cyclic prefix and obtain a length of Baseband signal to be demodulated ;

[0106] Step b403, proceed Point FFT transformation to obtain OFDM baseband demodulated signal ;

[0107] Specifically, in this embodiment, a 2048-point FFT transformation is performed;

[0108] Step b404, delete the zero carrier and obtain a length of Vector ;

[0109] Specifically, in this embodiment, the zero carriers are deleted, and the positions are the first 172 and the last 171;

[0110] Step b405, perform channel estimation based on the pilot pattern and obtain the channel response as ;

[0111] Step b406, perform equalization to obtain an equalized signal , which is calculated as:

[0112] ;

[0113] Step b407, delete the scattered pilot and continuous pilot data according to the pilot pattern, and obtain a length of communication signals And the corresponding constellation diagram; such as Figure 7 As shown, the corresponding constellation diagram can be obtained;

[0114] Step b408, perform QPSK constellation demapping to obtain the received binary bit stream communication data .

[0115] Furthermore, if Figure 4 As shown, in step 4, if it is radar reception, the specific method of performing radar reception processing and outputting detection parameters and detection results is:

[0116] Step c401, assume that the radar baseband receiving signal received by the USRP signal receiving module after passing through the channel is ,like Figure 8 As shown, first perform signal synchronization to obtain the accurate frame start position, and obtain OFDM symbols ;

[0117] Step c402, remove the cyclic prefix and obtain a length of Baseband signal to be demodulated ;

[0118] Step c403, proceed Point FFT transformation to obtain OFDM baseband demodulated signal ;

[0119] Step c404, delete the zero carrier and obtain a length of Vector ;

[0120] Step c405, calculate the channel response matrix, first calculate the channel response of each symbol :

[0121] ;

[0122] Will The channel response matrix is ​​constructed by :

[0123] H r = [ h 1 , r , h 2 , r ,..., h N sym , r ] T ;

[0124] in 1× , indicating the column vector of The channel response of symbols, i=1,2,3,..., , represents the matrix transpose, represents a complex domain;

[0125] Step c406, perform two FFT transformations and one modulo operation on the channel response matrix to obtain the range-Doppler matrix :

[0126] D = abs ( [ F N sym ( F N c H r ) T ] T ) ;

[0127] in It means taking the modulus of each element in the matrix. and Respectively Point FFT Matrix and Point FFT matrix, represents the field of real numbers; Figure 8 As shown, the range-Doppler matrix D is the intensity diagram shown;

[0128] Step c407, calculating and displaying radar detection resolution parameters, wherein the radar detection resolution parameters include range resolution, maximum unambiguous range, speed resolution, and maximum unambiguous speed;

[0129] The distance resolution The calculation method is:

[0130] ;

[0131] in represents the speed of light, Indicates the IQ rate, , ;

[0132] Maximum unambiguous distance The calculation method is:

[0133] ;

[0134] Speed ​​resolution The calculation method is:

[0135] ;

[0136] in Indicates the carrier frequency, , .

[0137] Maximum unambiguous speed The calculation method is:

[0138] .

[0139] In summary, the present invention can be used for target perception, detection and communication, and can add radar detection function to the system without losing communication performance.

[0140] Those skilled in the art will appreciate that the embodiments described are intended to help readers understand the principles of the present invention, and should be understood that the scope of protection of the present invention is not limited to the embodiments described. For those skilled in the art, the present invention may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A radar communication integrated transmission method based on USRP, characterized in that: The integrated radar communication transmission and receiving process is realized based on the USRP signal transmission module and the USRP signal receiving module. Specifically, the integrated radar communication transmission process includes the following steps: Step a1, set the device ID of the USRP signal transmission module and start the USRP transmission session; Step a2, configure the transmission parameters of the USRP signal transmission module, set the activation channel ID, data type, clock and frequency source, IQ rate, carrier frequency, transmission gain and antenna selection; Step a3, using a built-in MATLAB script to generate a radar communication integrated baseband waveform signal, outputting the real part and the imaginary part of the radar communication integrated baseband waveform signal respectively, and displaying the waveform and spectrum of the radar communication integrated baseband waveform signal; Step a4, setting the transmission mode, combining the real part and the imaginary part of the radar communication integrated baseband waveform signal into one path and writing it into the USRP signal transmission module to wait for transmission; Step a5, after the transmission is completed, close the USRP transmission session to complete the transmission of radar communication integration; The radar communication integrated receiving process comprises the following steps: Step 1, set the device ID of the USRP signal receiving module and start the USRP receiving session; Step 2: Configure the receiving parameters of the USRP signal receiving module, set the activation channel ID, data type, clock and frequency source, IQ rate, carrier frequency, receiving gain, and antenna selection; Step 3, enable USRP signal reception at the receiving end, and obtain the baseband receiving signal received by the USRP signal receiving module; Step 4, select communication reception or radar reception, input the baseband reception signal into the corresponding built-in MATLAB script for processing, if it is communication reception, perform communication reception processing and output the constellation diagram and communication data; If it is radar reception, radar reception processing is performed and detection parameters and detection results are output, and the following steps are performed: Step c401, assume that the radar baseband receiving signal received by the USRP signal receiving module after passing through the channel is First, perform signal synchronization to obtain the accurate frame start position and obtain OFDM symbols ; Step c402, remove the cyclic prefix and obtain a length of Baseband signal to be demodulated ; Step c403, proceed Point FFT transformation to obtain OFDM baseband demodulated signal ; Step c404, delete the zero carrier and obtain a length of Vector ; Step c405, calculate the channel response matrix, first calculate the channel response of each symbol : ； in, When generating radar communication integrated baseband waveform signals for MATLAB scripts, the discrete pilot and continuous pilot data are inserted according to the pilot pattern to obtain a length of A vector of Will The channel response matrix is ​​constructed by : ； in 1× , indicating the column vector of The channel response of symbols, i=1,2,3,..., , represents the matrix transpose, represents a complex domain; Step c406, perform two FFT transformations and one modulo operation on the channel response matrix to obtain the range-Doppler matrix : ； in It means taking the modulus of each element in the matrix. and Respectively Point FFT Matrix and Point FFT matrix, represents the field of real numbers; Step c407, calculating and displaying radar detection resolution parameters, wherein the radar detection resolution parameters include range resolution, maximum unambiguous range, speed resolution, and maximum unambiguous speed; The distance resolution The calculation method is: ； in represents the speed of light, Indicates IQ rate; Maximum unambiguous distance The calculation method is: ； Speed ​​resolution The calculation method is: ； in Indicates the carrier frequency; When generating the integrated baseband waveform signal for radar communication for the MATLAB script, insert the cyclic prefix and obtain the OFDM symbol vector Length; Maximum unambiguous speed The calculation method is: ； Step 5. Close the USRP receive session and exit the program.

2. According to the USRP-based radar communication integrated transmission method of claim 1, it is characterized in that: The specific method of using the built-in MATLAB script to generate the radar communication integrated baseband waveform signal in step a3 is: Step a301, for the generated binary bit stream communication data, based on The bit lengths are selected in sequence, where is the modulation order, is the number of data carriers; Bit length binary is recorded as binary bit stream communication data vector ; Step a302, convert the binary bit stream communication data vector Perform constellation mapping and obtain a length of The vector after constellation mapping ; Step a303, inserting scattered pilots and continuous pilot data according to the pilot pattern to obtain a length of Vector ; Step a304, insert zero carrier, and obtain a length of Vector ; Step a305, perform Point IFFT transformation to obtain OFDM baseband modulation signal ; Step a306, insert a cyclic prefix to obtain a length of OFDM symbol vector ; Step a307, OFDM symbols are combined into one frame, and a frame synchronization header is added to obtain the output radar communication integrated baseband waveform signal .

3. According to claim 2, a radar communication integrated transmission method based on USRP is characterized in that: If it is communication reception in step 4, the specific method of performing communication reception processing and outputting the constellation diagram and communication data is as follows: Step b401, assume that the communication baseband receiving signal received by the USRP signal receiving module after passing through the channel is First, perform signal synchronization to obtain the accurate frame start position and obtain OFDM symbols ; Step b402, remove the cyclic prefix and obtain a length of Baseband signal to be demodulated ; Step b403, proceed Point FFT transformation to obtain OFDM baseband demodulated signal ; Step b404, delete the zero carrier and obtain a length of Vector ; Step b405, perform channel estimation based on the pilot pattern and obtain the channel response as ; Step b406, perform equalization to obtain an equalized signal , which is calculated as: ； Step b407, delete the scattered pilot and continuous pilot data according to the pilot pattern, and obtain a length of communication signals And the corresponding constellation diagram; Step b408, perform constellation demapping to obtain the received binary bit stream communication data .

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