Signal transmitting method, device and system

Abstract

The invention discloses a signal transmitting method, device and system, and belongs to the technical field of radars. The method comprises the following steps: W transmitting antennas included in a transmitting antenna array transmit W signal sequences; wherein the W signal sequences are sequences obtained by adopting different phases to modulate, Doppler frequencies corresponding to the W signal sequences are located on N Doppler frequency bands at equal intervals, W Doppler frequency bands are occupied, and in addition, the target period autocorrelation sidelobe value lambda of the coding value of the W Doppler frequency bands is smaller than or equal to a predefined threshold value. The target period self-correlation sidelobe value lambda of the coding value of the W Doppler frequency bands reflects the overlapping number of Doppler frequencies of different signal sequences of different targets when multiple targets appear after the W signal sequences are transmitted. As lambda is smaller than or equal to the predefined threshold value, the signal sequence transmitted by the method can effectively control the overlapping number of Doppler frequencies, and the influence of frequency band crosstalk is further reduced.

Description

Signal transmission method, device and system Technical Field

[0001] The present application relates to the field of radar technology, and in particular to a signal transmission method, device and system. Background Art

[0002] With the development of radar technology, increasingly mature radar systems are widely used for target detection. A radar system transmits a signal sequence through a transmitting antenna. This signal sequence is reflected by the target being detected, forming an echo sequence. Target velocity is estimated based on the Doppler frequency of the echo sequence, which corresponds to the Doppler frequency of the signal sequence. However, during target detection, a radar system may use multiple transmitting antennas to transmit multiple signal sequences. For example, a multiple-input, multiple-output (MIMO) radar system includes a transmitting antenna array with multiple transmitting antennas. This radar system also generates multiple echo sequences. When multiple signal sequences are modulated using Doppler-frequency division multiplexing (DDM), the Doppler frequencies of different echo sequences fall at different Doppler frequency points in the Doppler band.

[0003] When using multiple transmitting antennas for target detection, multiple targets may be present at the same distance. In this case, a single signal sequence will reflect and form multiple echo sequences. If the speeds of the detected targets meet certain conditions, the Doppler frequencies of the different echo sequences from different targets will be the same. This means that the Doppler frequencies of the different echo sequences from different targets will overlap at the same Doppler frequency point, affecting signal quality.

[0004] Therefore, a signal transmission method is needed to reduce the number of Doppler frequencies of overlapping echo sequences when multiple targets are present.

[0005] Summary of the Invention

[0006] The present application provides a signal transmission method, device, and system to reduce the number of Doppler frequencies of overlapping echo sequences when there are multiple targets.

[0007] In a first aspect, the present application provides a signal transmission method, which is applied to a transmitting antenna array, the transmitting antenna array including W transmitting antennas, where W is a positive integer greater than 1. The method includes: the W transmitting antennas included in the transmitting antenna array transmit W signal sequences. The W signal sequences are sequences obtained by modulation using different phases, and the Doppler frequencies corresponding to the W signal sequences are located in W Doppler frequency bands among N equally spaced Doppler frequency bands, where N is a positive integer greater than 1, and N is greater than or equal to W. In addition, the target periodic autocorrelation sidelobe value λ of the code value of the W Doppler frequency bands is less than or equal to a predefined threshold.

[0008] The target periodic autocorrelation sidelobe value λ of the code values ​​for the W Doppler frequency bands reflects the amount of Doppler frequency overlap between different signal sequences for different targets when multiple targets are present after transmitting the W signal sequences. Because λ is less than or equal to a predefined threshold, the signal sequences transmitted using this method effectively control the amount of Doppler frequency overlap corresponding to the signal sequences, thereby reducing the impact of frequency band crosstalk.

[0009] In a second aspect, a signal transmitting device is provided, which is applied to a transmitting antenna array, the transmitting antenna array including W transmitting antennas, where W is a positive integer greater than 1, and the device includes: a transmitting module, used for the W transmitting antennas to transmit W signal sequences; the W signal sequences are modulated using different phases, and the Doppler frequencies corresponding to the W signal sequences are located on W Doppler frequency bands among N equally spaced Doppler frequency bands, where N is a positive integer greater than 1, and N is greater than or equal to W; the target periodic autocorrelation sidelobe value λ of the coding values ​​of the W Doppler frequency bands is less than or equal to a predefined threshold.

[0010] In a possible implementation of the first or second aspect, the phase of any one of the W signal sequences is determined based on code values ​​of the W Doppler frequency bands and an angle offset value corresponding to the signal sequence, where the angle offset value is obtained by dividing the angle period corresponding to the signal sequence into N equal parts. The phase to be used when modulating the signal sequence is determined based on the code values ​​of the W Doppler frequency bands and the angle period corresponding to the signal sequence, thereby ensuring modulation execution and improving reliability.

[0011] In a possible implementation of the first or second aspect, N is determined based on the number of signal states indicated by a signal modulation algorithm of the transmit antenna array, where the number of signal states represents the number of signal states modulated using the signal modulation algorithm. A total number N of Doppler frequency bands is determined based on the number of signal states, so that the Doppler frequency corresponding to the signal sequence in each state lies within a Doppler frequency band, thereby ensuring that target velocity estimation based on the Doppler frequency is performed and improving reliability.

[0012] In one possible implementation of the first or second aspect, when the number of signal states meets the frequency band requirement corresponding to the transmit antenna array, N is the number of signal states; or when the number of signal states does not meet the frequency band requirement corresponding to the transmit antenna array, N is the number of signal states that meets the frequency band requirement obtained by numerically expanding the number of signal states. N is determined based on the frequency band requirement corresponding to the transmit antenna array to ensure that the transmit antenna array supports the transmission of the signal sequence. In addition, different methods for determining N exist for different results of whether the frequency band requirement is met, providing high flexibility and wide versatility.

[0013] In a possible implementation of the first aspect or the second aspect, the coded values ​​of the W Doppler frequency bands include W elements assigned a first value and NW elements assigned a second value, with one element corresponding to one Doppler frequency band. The first value is used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the second value is used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence, and the first value and the second value are different values. The coded values ​​of the W Doppler frequency bands are used to represent the position of the Doppler frequency corresponding to each signal sequence on the N Doppler frequency bands, and the representation of the W Doppler frequency bands is clearer and more accurate. The first value can be 1, and the second value can be 0. This application does not limit the specific values ​​of the first value and the second value.

[0014] In a possible implementation of the first or second aspect, the predefined threshold is 1. The number of overlapping Doppler frequencies corresponding to different signal sequences for different targets is controlled to be at most 1, thereby reducing the number of overlapping Doppler frequencies. A target velocity estimation result obtained based on Doppler frequencies with a smaller number of overlapping frequencies has higher accuracy.

[0015] In a possible implementation of the first or second aspect, when N is 8 and W is 3, the encoding values ​​of the W Doppler frequency bands are any one of {11010000} and {11000010}, where one element of the encoding values ​​of the W Doppler frequency bands corresponds to one Doppler frequency band, 1 is a first value indicating that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and 0 is a second value indicating that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence. The encoding values ​​of the W Doppler frequency bands have multiple possibilities, providing high flexibility.

[0016] In a possible implementation of the first aspect or the second aspect, when the coding values ​​of the W Doppler frequency bands are {11010000}, the phases used by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 45°, 90°, 135°, 180°, 225°, 270°, 315°], and [0°, 135°, 270°, 45°, 180°, 315°, 90°, 225°]. The phase used by each signal sequence can be determined by the coding values ​​of the W Doppler frequencies, and the phase determination efficiency is high.

[0017] In a possible implementation manner of the first aspect or the second aspect, when N is 16 and W is 4, the coding values ​​of the W Doppler frequency bands are {1101000100000000}, {1101000000001000}, {1100101000000000}, {1100100000010000}, {1100010100000000}, {1100010000000010}, {11000010000000010}, {11000010000000100}, {1100000000100}, {1100000000 Any one of {0101000}, {1100000000100010}, {1100000000010100}, {1011000100000000}, and {1011000000001000}, where each element of the code values ​​of the W Doppler frequency bands corresponds to a Doppler frequency band, 1 is a first value indicating that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and 0 is a second value indicating that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence. There are multiple possible code values ​​for the W Doppler frequency bands, providing high flexibility. Furthermore, this signal transmission method can be applied to a transmit antenna array comprising three transmit antennas or a transmit antenna array comprising four transmit antennas, offering wide versatility.

[0018] In a possible implementation manner of the first aspect or the second aspect, when the coding values ​​of the W Doppler frequency bands are {1101000100000000}, the phases adopted by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, The phase used by each signal sequence can be determined by using W coding values ​​of Doppler frequencies, and the phase determination efficiency is high.

[0019] In a third aspect, a phase determination method is provided for determining the phase adopted by the signal sequence transmitted in any of the signal transmission methods described in the first aspect. The phase determination method is applied to a coding device, and the method includes: determining W according to the number of transmitting antennas, and determining N according to a signal adjustment algorithm; determining the number z of candidate codes that satisfy the (N, W, Y) distribution, where Y is a predefined threshold; based on z being less than 1, the coding device generates a λ-periodic autocorrelation sequence group, or, based on z being equal to 1, the coding device generates a (N, W, Y) unique code, or, based on z being greater than 1, the coding device generates a (N, W, Y) coding group; generating a phase coding sequence (group) based on the λ-periodic autocorrelation sequence group, the unique code or the coding group.

[0020] In a fourth aspect, a transmitting antenna array is provided, the transmitting antenna array including W transmitting antennas, and the W transmitting antennas are used to implement any signal transmission method described in the first aspect.

[0021] In a fifth aspect, a computer program product is provided, comprising a computer program or instructions, which are executed by a processor so that a computer controls the W transmitting antennas included in the transmitting antenna array to implement any signal transmission method described in the first aspect.

[0022] In a sixth aspect, a radar system is provided, the radar system including a transmitting antenna array, the transmitting antenna array including W transmitting antennas, and the transmitting antennas are used to implement any signal transmission method described in the first aspect.

[0023] In a seventh aspect, a detection device is provided, comprising: a transceiver, a memory, and a processor. The transceiver, the memory, and the processor communicate with each other via an internal connection path; the memory is configured to store instructions; and the processor is configured to execute the instructions stored in the memory to control W transmit antennas included in a transmit antenna array in the transceiver to perform the method according to the first aspect or any possible implementation of the first aspect.

[0024] Optionally, there are one or more processors and one or more memories.

[0025] Optionally, the memory may be integrated with the processor, or the memory may be provided separately from the processor.

[0026] In the specific implementation process, the memory can be a non-transitory memory, such as a read-only memory (ROM), which can be integrated on the same chip as the processor or be set on different chips. This application does not limit the type of memory and the setting method of the memory and the processor.

[0027] In the eighth aspect, a chip is provided, including a processor for calling and running program instructions or codes stored in the memory from the memory, and a communication device equipped with the chip includes a transmitting antenna array, and the transmitting antenna array includes W transmitting antennas, and the transmitting antennas are used to execute the methods in the above aspects.

[0028] In the ninth aspect, another chip is provided, comprising: an input interface, an output interface, a processor, and a memory, wherein the input interface, the output interface, the processor, and the memory are connected via an internal connection path, and the processor is used to execute the code in the memory. When the code is executed, the processor is used to control the W transmitting antennas included in the transmitting antenna array based on the communication connection to execute the methods in the above aspects.

[0029] It should be understood that the beneficial effects achieved by the technical solutions of the second to ninth aspects of this application and the corresponding possible implementation methods can be referred to the technical effects of the first aspect and its corresponding possible implementation methods mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG1 is a schematic diagram of a transmitting antenna array provided in an embodiment of the present application;

[0031] FIG2 is a schematic diagram of an application scenario of a radar system provided in an embodiment of the present application;

[0032] FIG3 is a schematic diagram of transmitting a signal sequence provided in an embodiment of the present application;

[0033] FIG4 is a schematic diagram of a spectrum provided in an embodiment of the present application;

[0034] FIG5 is a schematic diagram of frequency band crosstalk provided by an embodiment of the present application;

[0035] FIG6 is a statistical diagram of frequency band crosstalk numbers provided in an embodiment of the present application;

[0036] FIG7 is a flow chart of a phase determination method provided in an embodiment of the present application;

[0037] FIG8 is another spectrum diagram provided in an embodiment of the present application;

[0038] FIG9 is a schematic diagram of another frequency band crosstalk provided by an embodiment of the present application;

[0039] FIG10 is a statistical diagram of another frequency band crosstalk number provided in an embodiment of the present application;

[0040] FIG11 is a schematic structural diagram of a signal transmitting device provided in an embodiment of the present application;

[0041] FIG12 is a schematic structural diagram of a detection device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] The terms used in the embodiments of this application are only used to explain the specific embodiments of this application and are not intended to limit this application. To make the purpose, technical solutions and advantages of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings.

[0043] A radar system detects targets using a transmitting antenna array, which includes transmit (TX) antennas. These transmit antennas transmit a signal sequence. When the transmitted signal sequence encounters a target, it is reflected by the target, forming an echo sequence. The radar system performs a two-dimensional fast Fourier transform (FFT) on the echo sequence to determine its Doppler frequency, which is then used to estimate target velocity. This Doppler frequency is also the Doppler frequency corresponding to the signal sequence.

[0044] During target detection, a radar system may use multiple transmitting antennas. When the radar system uses multiple transmitting antennas to transmit multiple signal sequences, the radar system will also receive multiple echo sequences. Furthermore, when multiple signal sequences are modulated using Doppler frequency multiplexing, the Doppler frequencies of different echo sequences are located at different Doppler frequency points in the Doppler frequency band.

[0045] However, during target detection, multiple targets may be present at the same distance. In this case, a single signal sequence will be reflected by multiple targets, forming multiple echo sequences. Furthermore, as the detected target moves, the Doppler frequency of the target's echo sequence changes, and the Doppler frequency band occupied by the Doppler frequency of the echo sequence also shifts. In other words, when the speed of the detected targets meets certain conditions, the Doppler frequencies of different echo sequences from different targets may become the same. In other words, the Doppler frequencies of different echo sequences may overlap at the same Doppler frequency point within the same Doppler frequency band, causing signal distortion or errors.

[0046] The present application provides a signal transmission method, which modulates the phase of a transmitted signal sequence based on the correlation between the Doppler frequency band occupied by the Doppler frequency of an echo sequence and the phase of a signal sequence corresponding to the echo sequence, thereby reducing the number of Doppler frequencies of overlapping echo sequences when there are multiple targets.

[0047] Figure 1 is a schematic diagram of a transmit antenna array provided in an embodiment of the present application. Transmit antenna array 11 includes W transmit antennas, each of which is configured to transmit W signal sequences, such as signal sequence 1, signal sequence 2, and so on, in Figure 1 . The present embodiment does not limit the value of W; it can be any positive integer greater than 2, as shown in Figure 1 , or it can be any other value, for example, 2. The W signal sequences transmitted by the W transmit antennas are modulated using different phases.

[0048] In one possible implementation, the transmitting antenna array 11 is a transmitting antenna array included in a radar system. The radar system can be configured on any object to achieve target detection in different application scenarios. For example, the radar system is configured on an autonomous driving vehicle to achieve perception of the surrounding environment of the autonomous driving vehicle. Figure 2 is a schematic diagram of an application scenario of a radar system provided in an embodiment of the present application. Referring to Figure 2, a radar system includes a transmitting antenna array 11, and multiple radar systems are arranged at multiple positions on the vehicle body to transmit signal sequences in different directions to achieve measurement of the driving environment in different directions.

[0049] An embodiment of the present application provides a signal transmission method, which can be performed by a transmitting antenna array. The transmitting antenna array can be the transmitting antenna array 11 shown in FIG. 1 . The method includes S301.

[0050] S301, W transmitting antenna arrays transmit W signal sequences; the W signal sequences are modulated using different phases, and the Doppler frequencies corresponding to the W signal sequences are located in W Doppler frequency bands among N equally spaced Doppler frequency bands, where N is a positive integer greater than 1, and N is greater than or equal to W; the target periodic autocorrelation sidelobe value λ of the code values ​​of the W Doppler frequency bands is less than or equal to a predefined threshold.

[0051] In one possible implementation, W signal sequences are obtained by modulating an initial signal with different phases. Referring to FIG3 , the radar system including a transmitting antenna array further includes a plurality of phase shifters. The transmitter sends the initial signal to the phase shifters respectively, and the phase shifters modulate the initial signal according to different phases to obtain a signal sequence, and the modulated signal sequence is transmitted via the transmitting antenna. Exemplarily, the initial signal is a linear frequency modulation signal, such as a chirp signal, also known as a swept cosine signal. Of course, the initial signal can also be other types of coded signals. Furthermore, the W phase shifters can modulate an initial signal as shown in FIG3 to obtain W signal sequences, and the W phase shifters can also modulate multiple initial signals to achieve the acquisition of W signal sequences.

[0052] Optionally, during phase modulation of the initial signal, the phase of any one of the W signal sequences is determined based on code values ​​of the W Doppler frequency bands. The code values ​​of the W Doppler frequency bands are used to indicate frequency band distribution of the W Doppler frequency bands in N equally spaced Doppler frequency bands, and the W Doppler frequency bands are Doppler frequency bands in which the Doppler frequencies corresponding to the W signal sequences are located.

[0053] For example, the Doppler frequency corresponding to the signal sequence is consistent with the Doppler frequency of the echo sequence formed by the signal sequence reflected from the target. Therefore, the Doppler frequency band of the Doppler frequency corresponding to the signal sequence is also consistent with the Doppler frequency band occupied by the Doppler frequency of the echo sequence corresponding to the signal sequence. However, since the Doppler frequency of the echo sequence is a waveform, when determining the Doppler frequency band occupied by the Doppler frequency of the echo sequence, the Doppler frequency band corresponding to the peak of the Doppler frequency can be used as the Doppler frequency band of the Doppler frequency.

[0054] Taking the Doppler spectrum shown in Figure 4 as an example, the Doppler frequencies of three echo sequences are displayed: the Doppler frequency of the echo sequence from transmitting antenna 0, the Doppler frequency of the echo sequence from transmitting antenna 1, and the Doppler frequency of the echo sequence from transmitting antenna 2. Referring to Figure 4 , although the Doppler frequency of the echo sequence from transmitting antenna 2 occupies the Doppler frequency bands with band indices 1 to 8, the peak of the Doppler frequency of the echo sequence from transmitting antenna 2 corresponds to the Doppler frequency band with band index 4. Therefore, the Doppler frequency of the echo sequence from transmitting antenna 2 occupies the Doppler frequency band with band index 4 in the spectrum. In other words, the Doppler frequency corresponding to the signal sequence transmitted by transmitting antenna 2 is located in the Doppler frequency band with band index 4. The band index serves as an identifier for the Doppler frequency band, used to distinguish different Doppler frequency bands. The band index can be a number as shown in Figure 4 , or other elements, such as letters.

[0055] Therefore, before determining the phase used by any signal sequence, it is necessary to select the Doppler frequency band in which the Doppler frequencies corresponding to each signal sequence are located, that is, to determine the code values ​​for the W Doppler frequency bands. In one possible implementation, determining the code values ​​for the W Doppler frequency bands is performed by a coding device. This coding device can be a coding device configured within the radar system, or it can be a network device that is independent of the radar system and establishes a communication connection with the radar system via a wired or wireless network, such as a server or terminal, or other network device that supports data processing. The following example illustrates the process of determining the code values ​​for the W Doppler frequency bands, using the example of a coding device that is independent of the radar system.

[0056] For example, the encoding device can determine the Doppler frequency bands corresponding to the W signal sequences based on a predefined threshold, thereby selecting the frequency band distribution of the W Doppler frequency bands that meet the predefined threshold. Furthermore, based on the frequency band distribution of the W Doppler frequency bands, the encoding device needs to obtain the predefined threshold value. Regarding this process of determining the code values, since the determination of the code values ​​for the W Doppler frequency bands involves a predefined threshold value Y, the encoding device needs to obtain the predefined threshold value. This predefined threshold value indicates the maximum amount of overlap in Doppler frequencies corresponding to signal sequences of different targets that can be tolerated when there are multiple targets. Doppler frequency overlap of signal sequences refers to signal sequences with the same Doppler frequency and occupying the same Doppler frequency band. Alternatively, the predefined threshold value can be set based on the detection target. The detection target refers to the target operating the radar system for target detection. Alternatively, the predefined threshold value can be set based on experience. For example, the predefined threshold value can be set to 1 or 2 based on experience. Of course, the setting of the predefined threshold value can also refer to the implementation environment. The implementation environment may include, for example, the number of transmitting antennas included in the transmitting antenna array or the requirements of the application scenario of the radar system on the detection accuracy.

[0057] Regardless of which method is used to set the predefined threshold, the frequency band distribution that meets the predefined threshold can mean that when the Doppler frequencies of W echo sequences of a target are distributed on N Doppler frequency bands according to the frequency band distribution, even if multiple targets appear, the overlapping number of Doppler frequencies of different echo sequences of different targets will not exceed the predefined threshold.

[0058] In one possible implementation, the process of determining the distribution of W Doppler frequency bands by a coding device based on a predefined threshold includes: obtaining at least one candidate code, where each candidate code corresponds to a frequency band distribution of W Doppler frequency bands in N Doppler frequency bands; calculating a target periodic autocorrelation sidelobe value λ for each candidate code in the at least one candidate code, and screening out a candidate code whose λ is less than or equal to the predefined threshold from the at least one candidate code; and determining the code values ​​of the W Doppler frequency bands based on the screened candidate codes.

[0059] N indicates the total number of Doppler bands included in the Doppler spectrum within a signal cycle. Since the frequency length corresponding to the Doppler spectrum within a signal cycle is fixed, once the value of N is determined, the bandwidth of each Doppler band can be further determined based on the total number of Doppler bands. For example, dividing the bandwidth by N yields N equally spaced Doppler bands. By determining the bandwidths of the Doppler bands corresponding to different signal sequences, the bandwidths of the intervals between Doppler bands corresponding to different signal sequences can be further determined. When the bandwidths of the intervals between Doppler bands corresponding to different signal sequences are appropriately sized, the impact of Doppler frequency overlap can be effectively reduced. An appropriately sized interval between Doppler bands corresponding to different signal sequences means that even if multiple targets are present and moving, the movement of the Doppler frequencies corresponding to a signal sequence within the Doppler spectrum will not cause the Doppler frequencies corresponding to that signal sequence to overlap with those corresponding to other signal sequences. In other words, the Doppler frequencies corresponding to some signal sequences will overlap.

[0060] The above embodiment explains why the encoding device needs to determine the total number of frequency bands N and select W Doppler bands. The size of N can be determined based on the number of states indicated by the signal modulation algorithm of the transmitting antenna array. Both N and W are positive integers greater than 1, and N is greater than or equal to W. The signal modulation algorithm is an algorithm that modulates the initial signal to obtain a signal sequence, and the number of signal states is used to indicate the number of signal states modulated by the signal modulation algorithm. For example, Figure 3 shows the relationship between the initial signal and the signal sequence when the signal modulation algorithm is a phase modulation algorithm.

[0061] The embodiments of the present application do not limit the signal modulation algorithm used. It can be the phase modulation algorithm shown in Figure 3 above, or it can be a frequency modulation algorithm, or other modulation algorithms. The phase modulation algorithm is, for example, phase shift keying (PSK), and PSK is also divided into 2PSK, 4PSK, or 8PSK according to the different types of phases that can be shifted. Among them, 2PSK means that two phases can be modulated during phase modulation, that is, the number of signal states is 2. The meanings of 4PSK and 8PSK are similar to those of 2PSK and will not be repeated here. In other words, the encoding device can determine the number of signal states indicated by the signal modulation algorithm of the transmitting antenna array. Because signals in different states occupy different Doppler frequency bands on the Doppler spectrum, for example, the Doppler frequencies corresponding to signal sequences with different phases in the phase modulation algorithm occupy different Doppler frequency bands on the Doppler spectrum. Therefore, the Doppler spectrum needs to provide the corresponding Doppler frequency band for the signal sequence in each state. Based on this, the total number of frequency bands N can be determined according to the number of signal states.

[0062] In addition, when determining the total number of frequency bands, the encoding device will refer to the frequency band requirements corresponding to the transmitting antenna array in addition to the number of signal states. In one possible case, the frequency band requirements corresponding to the transmitting antenna array refer to the requirements for the total number of frequency bands determined by the hardware facilities of the radar system equipped with the transmitting antenna array. For example, the phase shifters included in the radar system need to ensure that the total number of frequency bands is a power of 2, and the frequency band requirements are determined to be a power of 2. Optionally, when the number of signal states meets the frequency band requirements corresponding to the transmitting antenna array, N is the number of signal states. Taking the frequency band requirement as a power of 2 as an example, if the number of signal states is 16, then 16=2 4 , which is a power of 2 and meets the frequency band requirement, the number of signal states (16) can be directly used as the total number of frequency bands N. Optionally, when the number of signal states does not meet the frequency band requirement corresponding to the transmit antenna array, N is the number of signal states that meets the frequency band requirement by numerically expanding the number of signal states. Continuing with the example of a frequency band requirement that is a power of 2, if the number of signal states is 7, since 7 is not a power of 2, 7 needs to be numerically expanded to 8 as the total number of frequency bands N.

[0063] After determining N, the encoding device counts the number of transmitting antennas in the transmitting antenna array. Under normal circumstances, that is, when there is only one target in the same range cell, each transmitting antenna transmits a signal sequence, which is reflected by a target to form an echo sequence. In other words, the number of Doppler frequencies of the echo sequence displayed on the Doppler spectrum is the same as the number of transmitting antennas. Therefore, the number of transmitting antennas can be used as the number of frequency bands to be occupied, W.

[0064] In one possible case, after the encoding device determines N and W, it will also determine whether there is a candidate code that satisfies (N, W, Y), and when the judgment result indicates that it exists, it continues to obtain the candidate code. The candidate code that satisfies (N, W, Y) means that the code length of the candidate code sequence is N, the number of first values ​​is W, and the corresponding target periodic autocorrelation sidelobe value is not greater than the predefined threshold Y. Optionally, the encoding device uses the Johnson bound distribution to determine the number z of candidate codes that conform to the (N, W, Y) distribution. For the case where z is less than 1, that is, when there is no candidate code that satisfies (N, W, Y), in this case, although the candidate code that satisfies the predefined threshold Y does not exist, it is still possible to find a candidate code that satisfies Y+1, or Y+2... etc. Therefore, the candidate code with the lowest target periodic autocorrelation sidelobe value λ can be used as the periodic autocorrelation sequence of λ. For example, the candidate code with λ being the smallest positive integer greater than Y is used as the periodic autocorrelation sequence of λ. Subsequently, the encoding device may determine encoding values ​​of the W Doppler frequency bands based on the frequency band distribution indicated by the determined periodic autocorrelation sequence.

[0065] The target periodic autocorrelation sidelobe value is used to indicate the maximum number of overlapping Doppler frequencies of different targets, when the Doppler frequencies corresponding to the candidate codes are distributed on the Doppler spectrum according to the frequency band occupancy corresponding to the candidate codes. If multiple targets are present and the Doppler frequency of one target changes, that is, the occupied Doppler frequency band shifts, then the maximum number of overlapping Doppler frequencies of different targets is. Optionally, the process of obtaining a periodic autocorrelation code sequence that satisfies λ of Y+1 or Y+2… and determining the code values ​​of W Doppler frequency bands based on the periodic autocorrelation code sequence is similar to the process of obtaining candidate codes and determining the code values ​​of W Doppler frequency bands based on the candidate codes. Reference may be made to the relevant description and is not further elaborated here.

[0066] When z is greater than or equal to 1, that is, when a candidate code satisfies (N, W, Y), the encoding device can select W Doppler bands from the N Doppler bands, thereby obtaining a frequency band distribution of the W Doppler bands. The encoding device then determines from the frequency band distributions that the frequency band distribution meets a predefined threshold and uses this as the Doppler frequency band distribution corresponding to each signal sequence. Because at least one frequency band distribution exists depending on the values ​​of N and W, and each frequency band distribution has a candidate code representing it, the encoding device can determine at least one candidate code based on the at least one frequency band distribution.

[0067] Optionally, the process of determining the candidate codes includes: obtaining an initial code with a code length of N, wherein an element in the initial code is used to indicate a Doppler frequency band; and determining the candidate codes according to the initial code and the frequency band distribution. Since the process of determining the corresponding candidate codes according to different frequency band distribution conditions is similar, one of the frequency band distribution conditions is taken as an example to explain the process of determining the candidate codes, and other frequency band distribution conditions can refer to the relevant description. Exemplarily, the encoding device assigns a first value to the elements corresponding to the W occupied Doppler frequency bands in the initial code, and assigns a second value to the elements corresponding to the NW unoccupied Doppler frequency bands in the initial code, according to any frequency band distribution condition, to obtain the candidate codes corresponding to any frequency band distribution condition, and the first value and the second value are different numerical values.

[0068] The code length of the initial code is N, which means that the initial code includes N elements. The Doppler frequency bands corresponding to the elements here can refer to the order in which the Doppler frequency bands are arranged in the N Doppler frequency bands, which is the same as the order in which the elements are arranged in the initial code. Because the frequency band distribution clearly specifies which of the N Doppler frequency bands are occupied by the Doppler frequencies corresponding to the signal sequence and which are not occupied by the Doppler frequencies corresponding to the signal sequence, the elements in the initial code used to indicate these occupied Doppler frequency bands can be assigned a first value based on the occupied Doppler frequency bands indicated in the frequency band distribution. The elements in the initial code used to indicate these unoccupied Doppler frequency bands can be assigned a second value based on the unoccupied Doppler frequency bands indicated in the frequency band distribution. In addition, since the initial values ​​of the N elements included in the initial encoding can be arbitrary values, the N elements can be the second value, and the encoding device only needs to assign the elements corresponding to the occupied Doppler frequency band to the first value, and there is no need to perform the operation of assigning the elements corresponding to the unoccupied Doppler frequency band to the second value.

[0069] Taking the first value as 1, the second value as 0, N as 8, and W as 3 as an example, the initial code is {00000000}, and the encoding device selects the first, second, and fourth Doppler bands from the 8 Doppler bands as the Doppler bands occupied by the Doppler frequencies corresponding to the W signal sequences. According to the frequency band distribution, the elements corresponding to the occupied Doppler bands are assigned the first value, that is, the first element, the second element, and the fourth element are assigned 1, and the resulting candidate code is {11010000}. Of course, the initial value of the element in the initial code can also be the first value, and the encoding device can assign the element corresponding to the unoccupied Doppler band to the second value. In addition, the embodiment of the present application does not limit the first value and the second value. As shown in the above embodiment, the first value can be 1 and the second value can be 0. The first value and the second value can also be a combination of other different numbers.

[0070] It should be noted that for a candidate code, the new code obtained by cyclic shifting it is identical to the frequency band occupancy indicated by the candidate code, as the Doppler spectrum itself is also a cyclically shifted image. Therefore, the frequency band occupancy indicated by the shifted code is the same as that indicated by the candidate code. The candidate code and the shifted code can be considered equivalent. This application uses the candidate code as an example to describe the process of determining the code values ​​for W Doppler frequency bands.

[0071] After obtaining at least one candidate code, the coding device starts to calculate the target periodic autocorrelation sidelobe value of the candidate code. Optionally, the relevant calculation formula for the target periodic autocorrelation sidelobe value when calculating two targets is as shown in Formula 1.

[0072]

[0073] Among them, x t is the first element included in the candidate encoding, x t+τ is the second element included in the shift encoding of the candidate code, N is the total number of frequency bands, which is also the total number of first elements included in the candidate code, and τ is the number of rightward shift bits. Taking the candidate code {11010000} as an example, the shift encoding of this candidate code has the following eight results.

[0074]

[0075] The 8×8 subscript in the above matrix indicates that the shift code has a code length of 8, and there are eight possible shifts for each candidate code. For example, when the number of shift bits is 0, the shift code is {11010000}, and when the number of shift bits is 1, the shift code is {01101000}. Similar to candidate codes, shift codes are also used to represent frequency band distribution.

[0076] Since the shift sequence clarifies the frequency band distribution of the Doppler frequencies corresponding to the signal sequences of other targets on N equally spaced Doppler frequency bands when there are other targets. The candidate sequence can also represent the frequency band distribution of the Doppler frequencies corresponding to the signal sequence of a target on the same set of N equally spaced Doppler frequency bands. Therefore, by combining the candidate sequence and the shift sequence, the frequency band crosstalk corresponding to the candidate code when there are multiple targets can be obtained. Figure 5 is a frequency band crosstalk schematic diagram provided in an embodiment of the present application, which shows the frequency band crosstalk corresponding to the candidate code {11010000}. 1-8 as frequency band indexes in Figure 5 are used to distinguish different Doppler frequency bands. The circles in Figure 5 are the Doppler frequency bands occupied by the Doppler frequencies corresponding to the three signal sequences of the target when the detected target is stationary, that is, the frequency band distribution indicated by the candidate code. The diamonds in Figure 5 are the Doppler frequency bands occupied by the Doppler frequencies corresponding to the three signal sequences of the target when the detected target is moving, that is, the frequency band distribution indicated by the shift code.

[0077] Referring to Figure 5 , when the detected target's velocity produces a single aliasing event, the corresponding offset bit number is 1. The Doppler frequencies corresponding to the three signal sequences also change, as shown on the Doppler spectrum diagram as the Doppler frequencies corresponding to the three signal sequences shifting sequentially to the three Doppler frequency bands 2, 3, and 5, i.e., the frequency band distribution indicated by the shift code {01101000}. The shifts indicated by the other diamonds in Figure 5 are similar to those when the target's velocity produces a single aliasing event, and will not be described in detail here. Furthermore, since the second target's offset bit number is 0 when stationary, its frequency band distribution is consistent with the circular distribution shown in Figure 5 and is not repeated with diamonds.

[0078] After the coding device generates the corresponding shift code based on the candidate code, it can calculate the initial periodic autocorrelation sidelobe value of the candidate code based on the shift code, so as to determine the target periodic autocorrelation sidelobe value of the candidate code based on the initial periodic autocorrelation sidelobe value of the candidate code. Taking the offset bit τ as 1 as an example, the candidate code is {11010000}, and the shift code obtained by shifting it 1 bit to the right is {01101000}. Then the initial periodic autocorrelation sidelobe value is the sum of the first element x in the candidate code. t Multiply by the shift encoding with x t The corresponding second element x t+τ , after obtaining multiple products, calculate the sum of the multiple products.

[0079] Optionally, the second element corresponding to the first element means that the first element and the second element are used to represent the same Doppler frequency band. In one possible case, when the arrangement order of the second element in the shift code is the same as the arrangement order of the first element in the candidate code, the second element and the first element represent the same Doppler frequency band and belong to corresponding elements. λ(1) calculated based on formula 1 = {11010000}☉{01101000} = sum({0 1 0 0 0 0 0 0}) = 1. Wherein, ☉ refers to dot product and sum refers to summation.

[0080] Taking the example of a first value of 1, a second value of 0, and an offset of 1, the calculation principle of Formula 1 above is explained. A first element in the candidate code equal to 1 indicates that the Doppler frequency band corresponding to that first element is occupied by the Doppler frequency of an echo sequence from target A. A second element in the shift code equal to 1 also indicates that the Doppler frequency band corresponding to that second element is occupied by the Doppler frequency of target B. For a Doppler frequency band, if it is occupied by the Doppler frequency of an echo sequence from both target A and target B—that is, the Doppler frequencies of different echo sequences from target A and target B are the same—frequency crosstalk exists in that Doppler frequency band. Since both the first and second elements corresponding to this Doppler frequency band are 1, the product of the two elements is 1. If a Doppler frequency band is not occupied by the Doppler frequencies of the echo sequences of target A and target B at the same time, for example, it is occupied by the Doppler frequency of the echo sequence of only one target, or the Doppler frequencies of the echo sequences of both targets are not occupied, that is, there is no frequency band crosstalk in the Doppler frequency band, then the product of the two elements will be equal to 0 because at least one element is 0.

[0081] It can be understood that by multiplying the corresponding first element and the second element, the product obtained can reflect whether frequency band crosstalk occurs in the Doppler frequency bands corresponding to the two elements. For example, the above example {01000000} indicates that frequency band crosstalk exists at the second Doppler frequency band. Therefore, the number of Doppler frequency bands where frequency band crosstalk occurs can be directly determined based on the product as the initial periodic autocorrelation sidelobe value. For the case where the first value is set to 1 and the second value is set to 0, the value used to indicate frequency band crosstalk is 1, and the value used to indicate the absence of frequency band crosstalk is 0. Therefore, the sum of each product is the sum of at least one 1, and its value is equal to the number of 1s. The sum of the products can be directly used as the initial periodic autocorrelation sidelobe value, which is convenient to operate.

[0082] Formula 1 can be used to calculate the initial periodic autocorrelation sidelobe value when the other target is moving at a different speed, that is, when the number of offset bits is different. In one possible case, for the same candidate code, the initial periodic autocorrelation sidelobe value calculated is also different when the number of offset bits is different. Continuing with the candidate code and offset code shown in Figure 5 as an example, the initial periodic autocorrelation sidelobe value for different offset bits is determined through a statistical graph. When the number of offset bits is 4, that is, when target A is stationary and target B is moving at a speed that produces four times aliasing, the Doppler frequencies of target A's echo sequence occupy three Doppler bands, 1, 2, and 4, respectively, while the Doppler frequencies of target B's echo sequence occupy three Doppler bands, 5, 6, and 8, respectively. The Doppler frequencies of target A's echo sequence and target B's echo sequence do not overlap, and the number of Doppler bands where frequency band crosstalk occurs is 0. The initial periodic autocorrelation sidelobe value of the candidate code is 0, which is different from the initial periodic autocorrelation sidelobe value when the number of offset bits is 1. The frequency band crosstalk caused by other motion conditions can be seen in Figure 5 and will not be further described here. Based on the frequency band crosstalk caused by different target motion conditions in Figure 5, a statistical chart of the initial periodic autocorrelation sidelobe values ​​is obtained, as shown in Figure 6. As shown in Figure 6, the initial periodic autocorrelation sidelobe values ​​of the same candidate code vary depending on the number of offset bits.

[0083] Since the initial periodic autocorrelation sidelobe values ​​calculated by different offset bits may be different, when the coding device screens the candidate codes, it is to ensure that according to the frequency band distribution corresponding to the candidate code, no matter how the second target moves, the number of frequency band crosstalk will not exceed the predefined threshold. Therefore, the coding device selects the largest initial periodic autocorrelation sidelobe value from the multiple initial periodic autocorrelation sidelobe values ​​of the candidate codes as the target periodic autocorrelation sidelobe value λ and compares it with the predefined threshold, and then determines the candidate code whose λ is less than or equal to the predefined threshold, that is, the candidate code that satisfies (N, W, Y). In addition, since the present application considers reducing the number of overlapping Doppler frequencies corresponding to different signal sequences of different targets, the situation where the offset bit is 0 is that the Doppler frequencies corresponding to the same signal sequence of different targets overlap. Therefore, when selecting the target periodic autocorrelation sidelobe value, the initial periodic autocorrelation sidelobe value corresponding to the offset bit being 0 is not considered.

[0084] After screening at least one candidate code through the above-mentioned screening operation, a candidate code can be selected as the code value of W Doppler frequency bands based on the screened candidate codes. The selection of the candidate code can be random selection or selection according to the position of the first value in the candidate code. Alternatively, the candidate code with the smallest target period autocorrelation sidelobe value can be selected according to the size of the target period autocorrelation sidelobe value, and the embodiment of the present application does not limit this. The minimum target period autocorrelation sidelobe value can be that the numerical value of the target period autocorrelation sidelobe value of the candidate code is smaller than the numerical value of the target period autocorrelation sidelobe value of other candidate codes, or the number of target period autocorrelation sidelobe values ​​of the candidate code is less than the number of target period autocorrelation sidelobe values ​​of other candidate codes. The number of target period autocorrelation sidelobe values ​​refers to the number of initial period autocorrelation sidelobe values ​​in the candidate code that is the same size as the target period autocorrelation sidelobe value.

[0085] For the transmit antenna array's frequency band occupancy, in the case where the first, second, and fourth Doppler bands are occupied by the Doppler frequencies corresponding to the signal sequence, as in the example above, the Doppler spectrum of the transmit antenna array is shown in Figure 4. The transmit antenna array includes three transmit antennas: transmit antenna 0, transmit antenna 1, and transmit antenna 2. The horizontal axis of the Doppler spectrum corresponding to the transmit antenna array represents frequency, which is divided into eight equally spaced Doppler bands. The Doppler frequency corresponding to transmit antenna 0 occupies the first Doppler band, the Doppler frequency corresponding to transmit antenna 1 occupies the second Doppler band, and the Doppler frequency corresponding to transmit antenna 2 occupies the fourth Doppler band. The remaining five Doppler bands are unused. According to the initial periodic autocorrelation sidelobe values ​​of each offset bit number shown in FIG6 , when the Doppler frequency of the transmitting antenna array is distributed on 8 equally spaced Doppler frequency bands according to the spectrum distribution shown in FIG4 , even if the target to be detected is moving, frequency band crosstalk will only occur in one Doppler frequency band at most. This can effectively control the number of Doppler frequency bands where frequency band crosstalk occurs, thereby reducing the impact of frequency band crosstalk.

[0086] Based on the above example, it can be understood that when the Doppler frequencies corresponding to the W signal sequences are distributed on the Doppler spectrum according to the code values ​​of the W Doppler frequency bands, the amount of Doppler frequency overlap can be effectively reduced, thereby reducing the impact of frequency band crosstalk. However, the occupied Doppler frequency bands determined in the above embodiment refer to the Doppler frequency bands occupied by the Doppler frequencies of the echo sequence on the Doppler spectrum after the echo sequence is subjected to two-dimensional FFT processing. Because the Doppler frequency band occupied by the Doppler frequencies of the echo sequence is related to the phase of the signal sequence corresponding to the echo sequence, it is also necessary to determine the phases used by the respective signal sequences corresponding to the frequency band occupancy, so that the Doppler frequencies corresponding to the signal sequences of each transmitting antenna can be distributed on the Doppler spectrum according to the frequency band distribution indicated by the code values ​​of the W Doppler frequency bands.

[0087] Exemplarily, the phase used by any one of the W signal sequences is determined based on the code values ​​of the W Doppler frequency bands and the angular offset value corresponding to any one of the signal sequences, and the angular offset value is obtained by dividing the angular period corresponding to any one of the signal sequences into N equal parts. Based on the situation where the W signal sequences are modulated using different phases to obtain the initial signal, the angular period corresponding to any one of the signal sequences is also the angular period of the initial signal corresponding to the any one of the signal sequences. The angular period of the initial signal refers to the angle of phase change when the initial signal, as a periodic signal, completes one cycle of signal change, and the angular period is, for example, 360 degrees (°).

[0088] In one possible implementation, the phase adopted by any signal sequence is determined based on the coding values ​​of W Doppler frequency bands and the angular offset value corresponding to any signal sequence, which is performed by a coding device. The angular period of the initial signal is divided by N, and the resulting quotient is used as the difference between adjacent angles included in the division result. The various angular offset values ​​included in the division result are determined based on the difference between adjacent angles and the initial value of the angular period, thereby obtaining N equally spaced angular offset values. The equally spaced here means that the difference between any two adjacent angular offset values ​​is equal. Taking the angular period of the initial signal as 360°, the initial value as 0°, and N as 8 as an example, the calculated quotient is 45°, and the 8 equally spaced angular offset values ​​obtained are 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°, respectively.

[0089] The encoding device can then determine the phase used by the signal sequence based on the N angle offset values ​​and the code values ​​of the W Doppler frequency bands. The code values ​​of the W Doppler frequency bands are used to determine the angle offset value corresponding to any signal sequence, and the angle offset value corresponding to any signal sequence is used to determine a phase coding sequence, which is used to indicate the phase used by the signal sequence at different times. Optionally, the process of determining the angle offset value corresponding to any signal sequence includes: determining the order of the code values ​​of the Doppler frequency bands matching any signal sequence in the W Doppler frequency bands, and selecting the angle offset value that matches the order of the order from the division results as the angle offset value corresponding to any signal sequence.

[0090] The embodiments of the present application do not limit the matching method of the signal sequence and the Doppler frequency band. The encoding device can determine the arrangement order of each signal sequence and determine the Doppler frequency band that matches each signal sequence based on the arrangement order of each signal sequence. The arrangement order of each signal sequence can be determined based on the identifier of the transmitting antenna that transmits the signal sequence. Optionally, the identifier of the transmitting antenna includes a number. For example, the identifiers of the three transmitting antennas included in the transmitting antenna array are TX0, TX1, and TX2, respectively. In this case, the three transmitting antennas can be arranged in sequence according to the numbers 0, 1, and 2 in the identifier, thereby obtaining the arrangement order of the signal sequences transmitted by the three transmitting antennas.

[0091] For example, the matching Doppler band is determined based on the order of the signal sequence. The Doppler band corresponding to the first element of the W Doppler band code values ​​is determined as the matching Doppler band for the signal sequence with the first order, and the same applies to the remaining signal sequences. For example, if the W Doppler band code values ​​are {11010000}, the matching Doppler band for the signal sequence of TX0 is the Doppler band corresponding to the first element, and the order of this Doppler band is first. The matching Doppler band for the signal sequence of TX1 is the Doppler band corresponding to the second element, and the order of this Doppler band is second. The matching Doppler band for the signal sequence of TX2 is the Doppler band corresponding to the fourth element, and the order of this Doppler band is fourth.

[0092] Of course, the encoding device may also determine the Doppler frequency bands that match the signal sequence according to a random matching principle, and further determine the order of arrangement of the matched Doppler frequency bands in the N Doppler frequency bands. In other words, the matching principle followed by the encoding device in determining the Doppler frequency bands that match the signal sequence is actually a one-to-one matching principle. The embodiment of the present application does not limit the method for determining the corresponding relationship.

[0093] After determining the order of the Doppler frequency bands that match each signal sequence, the angle offset values ​​with the same order are selected as the phase increments of the phase coding sequence for the signal sequence based on the order of the multiple angle offset values ​​in the division results. Taking the division results of 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315° as an example, in the above embodiment, the order of the Doppler frequency bands that match the signal sequence TX0 is 1. The first angle offset value 0° in the division results is selected as the phase increment, and the phase coding sequence c0 of the signal sequence TX0 is determined to be [0°, 0°, 0°, 0°, 0°, 0°, 0°]. The order of the Doppler frequency bands that match the signal sequence TX1 is 2. The second angle offset value 45° in the division results is selected as the phase increment, and the phase coding sequence c1 of the signal sequence TX1 is determined to be [0°, 45°, 90°, 135°, 180°, 225°, 270°, 315°]. The arrangement order of the Doppler frequency bands that match the signal sequence of TX2 is 4. The fourth angle offset value 135° in the division result is selected as the phase increment, and the phase coding sequence of the signal sequence of TX2 is determined to be c2 = [0°, 135°, 270°, 45°, 180°, 315°, 90°, 225°].

[0094] The phase coding sequence of any signal sequence refers to the signal sequence obtained by cyclically modulating the initial signal according to the phase indicated by the phase coding sequence. Taking the signal sequence of transmitting antenna TX1 as an example, the signal sequence transmitted by TX1 in the first transmission cycle, for example, adopts a phase of 0°, the signal sequence transmitted in the second transmission adopts a phase of 45°, and the signal sequence transmitted in the third transmission adopts a phase of 90°. The phase coding sequence can clearly define the phase adopted by the signal sequence at different times. When the signal sequence is a sequence modulated according to the phase indicated by the phase coding sequence, the Doppler frequency band occupied by the Doppler frequency corresponding to the signal sequence is also the Doppler frequency band indicated by the code values ​​of the W Doppler frequency bands.

[0095] The above example illustrates the process of the encoding device determining the phase used for each signal sequence. In one possible implementation, after determining the phase coding sequence, the encoding device sends the phase coding sequence of each signal sequence to the radar system. The phase coding sequence of each signal sequence is used by the radar system to perform phase shifting processing on the initial signal so that the transmitting antenna array can receive the modulated signal sequence and transmit the signal sequence outward. Exemplarily, the encoding device sends the phase coding sequence of each signal sequence to the phase shifter corresponding to each transmitting antenna. The phase shifter performs phase shifting processing on the received initial signal according to the phase indicated in the phase coding sequence to achieve signal modulation. Each phase shifter then sends the phase-shifted signal sequence to the transmitting antenna array. The transmitting antenna array radiates the signal sequence into space through the W transmitting antennas included therein to estimate the target speed.

[0096] It should be noted that the above example is intended to illustrate the process of determining the phase used by the signal sequence, and does not limit the total number of frequency bands N or the number of frequency bands to be occupied W. Furthermore, the code values ​​for the determined W Doppler frequency bands can exist in various situations. For example, when N is 8, W is 3, and the predefined threshold is 1, the code values ​​for the W Doppler frequency bands can be {11000010} in addition to {11010000} in the above embodiment. Alternatively, when the method of the present application is used to determine the phases adopted by four signal sequences according to the limitation that N is 16, W is 4, and the predefined threshold is 1, the coding values ​​of the W Doppler frequency bands involved in the phase determination process can be {1101000100000000}, {1101000000001000}, {110010100000000}, {1100100000010000}, {110001010100 000000}, {1100010000000010}, {1100001000000100}, {1100000000101000}, {1100000000100010}, {1100000000010100}, {1011000100000000}, and {1011000000001000}, which are not limited in the embodiments of the present application. In which, one element of the coded values ​​of the W Doppler frequency bands in the above example corresponds to one Doppler frequency band, 1 is a first value used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and 0 is a second value used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence.

[0097] In addition, the expression of the code values ​​of the W Doppler frequency bands involved in the embodiments of the present application can be a binary code value composed of "1" and "0" as shown in the above embodiment, or a sequence of other code lengths composed of other numbers. For example, when determining the angle offset value corresponding to any signal sequence based on the code values ​​of the W Doppler frequency bands, a target sequence with a code length of W can be used to express the code values ​​of the W Doppler frequency bands in another way. The target sequence with a code length of W includes W elements, one element is used to indicate a Doppler frequency band occupied by a Doppler frequency corresponding to the signal sequence, and the value of the element is used to indicate the arrangement order of the Doppler frequency band occupied by the Doppler frequency corresponding to the signal sequence in N equally spaced Doppler frequency bands. Taking the code value of the W Doppler frequency bands as {11010000} as an example, the corresponding target sequence is [1, 2, 4]. The arrangement order of the W Doppler frequency bands is clarified through the target sequence, so as to facilitate the subsequent determination of the angle offset value corresponding to any signal sequence based on the arrangement order of the W Doppler frequency bands.

[0098] In summary, the signal transmission method provided in the embodiment of the present application has a predefined threshold that reflects the maximum value of the number of Doppler frequency overlaps that can be tolerated. The predefined threshold is used as a constraint to determine the phase adopted by each signal sequence that meets the constraint. The signal sequence obtained by signal modulation according to the determined phase can optimize the frequency band distribution of the Doppler frequency corresponding to the signal sequence after transmission, effectively reducing the number of Doppler frequency overlaps and reducing the impact range of frequency band crosstalk, thereby controlling signal distortion and improving signal quality. The target speed obtained based on a higher quality signal has higher accuracy. In addition, the phase adopted will also be determined according to the frequency band requirements corresponding to the transmitting antenna array to ensure that the obtained phase is applicable to the transmitting antenna array and has wide versatility. For a certain number of transmitting antennas, multiple coding values ​​of W Doppler frequency bands can be determined, and there are also multiple results for the phase adopted by the signal sequence, which is highly flexible.

[0099] An embodiment of the present application provides a phase determination method for determining the phase adopted by the signal sequence transmitted in the signal transmission method shown in the above embodiment. The flowchart of the phase determination method is shown in Figure 7. The phase determination method can be executed by an encoding device.

[0100] S801: Determine W according to the number of transmitting antennas.

[0101] Optionally, the process of determining W by the encoding device is similar to the process of determining W in S301 of the above embodiment, and reference may be made to the relevant description, which will not be repeated here.

[0102] S802: Determine N according to a signal modulation algorithm.

[0103] Optionally, the process of determining N by the encoding device is similar to the process of determining N in S301 of the above embodiment, and reference may be made to the relevant description, which will not be repeated here.

[0104] S803: Set a predefined threshold Y.

[0105] Optionally, the process of determining Y by the encoding device is similar to the process of determining Y in S301 of the above embodiment, and reference may be made to the relevant description, which is not repeated here. For example, Y is set to 1. In addition, the operations of S801-S803 above can be performed synchronously or asynchronously according to other operation sequences.

[0106] S804: Determine the number z of candidate codes that satisfy the (N, W, Y) distribution.

[0107] Optionally, the process of determining the number z of candidate codes satisfying the (N, W, Y) distribution is similar to the process of determining the number z of candidate codes satisfying the (N, W, Y) distribution in the above embodiment S301. Please refer to the relevant description and will not be repeated here.

[0108] S805: Determine whether z is greater than or equal to 1.

[0109] Determine whether z is greater than or equal to 1. If z is not greater than or equal to 1, that is, there is no candidate code that meets the (N, W, Y) distribution, the encoding device performs operation S806. If z is greater than or equal to 1, perform operation S807.

[0110] S806: Based on z being less than 1, the encoding device generates a λ-periodic autocorrelation sequence group.

[0111] At this point, no candidate code satisfies threshold Y, but candidate codes that satisfy thresholds Y+1, Y+2, etc. can still be found. Therefore, the candidate code with the lowest target cyclic autocorrelation sidelobe value is stored, and a lambda cyclic autocorrelation sequence group is generated. Optionally, the process of generating a cyclic autocorrelation sequence group is similar to the process of generating a cyclic autocorrelation sequence in S301 of the above embodiment. For details, please refer to the relevant description and will not be repeated here.

[0112] S807: Determine whether z is equal to 1.

[0113] It is determined whether z is equal to 1. If z is equal to 1, the encoding device performs the operation of S808. When z is not equal to 1, the encoding device performs the operation of S809.

[0114] S808 , based on z being equal to 1, the encoding device generates a unique code (N, W, Y).

[0115] Optionally, the encoding device generates candidate codes and selects a candidate code that conforms to the (N, W, Y) distribution from the candidate codes. Since there is only one candidate code that conforms to the (N, W, Y) distribution, the obtained candidate code that conforms to the (N, W, Y) distribution is a unique code, which can be directly used as the code value for the W Doppler frequency bands. The process of generating candidate codes is similar to the process of generating candidate codes in the above embodiment S301, and reference may be made to the relevant description, which is not repeated here.

[0116] S809 , based on z being greater than 1, the encoding device generates an encoding group of (N, W, Y).

[0117] Optionally, since z is greater than , indicating that there are multiple candidate codes that conform to the (N, W, Y) distribution, that is, there are multiple candidate codes screened according to the predefined threshold Y. Therefore, the encoding device can use each candidate code as a code value for W Doppler frequency bands to obtain a code group. The process of the encoding device obtaining the code value is similar to the process of generating a unique code in S808 and is not further described here. Optionally, when N is 16, W is 4, and Y is 1, the code group determined by the encoding device includes {1101000100000000}.

[0118] S810: Generate a phase coding sequence (group) according to a λ-periodic autocorrelation sequence group, a unique code or a coding group.

[0119] Optionally, the process of the encoding device generating a phase coding sequence (group) is similar to the process of generating a phase coding sequence in the above embodiment S301, and the relevant description may be referred to, which will not be repeated here. The phase coding sequences of each signal sequence generated based on {1101000100000000} are: the phase coding sequence of the signal sequence of transmitting antenna 0 [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], the phase coding sequence of the signal sequence of transmitting antenna 1 [0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, 315°, 337.5°], The phase coding sequence of the signal sequence of transmitting antenna 2 is [0°, 67.5°, 135°, 202.5°, 270°, 337.5°, 45°, 112.5°, 180°, 247.5°, 315°, 22.5°, 90°, 157.5°, 225°, 292.5°] and the phase coding sequence of the signal sequence of transmitting antenna 3 is [0°, 157.5°, 315°, 112.5°, 270°, 67.5°, 225°, 22.5°, 180°, 337.5°, 135°, 292.5°, 90°, 247.5°, 45°, 202.5°].

[0120] S811, the encoding device sends the phase encoding sequence (group).

[0121] Optionally, the encoding device sends the generated phase coding sequence (group) to the radar system. The sending process is similar to the process of sending the phase coding sequence in the above-mentioned embodiment S301. Please refer to the relevant description and will not be repeated here. In one possible implementation, when the radar system performs phase modulation according to the four phase coding sequences exemplified in S810 to obtain four signal sequences, and transmits the four signal sequences outward through the transmitting antenna array, the distribution of the Doppler frequencies of the obtained echo sequences on the Doppler spectrum is shown in Figure 8. The Doppler frequency of the echo sequence of transmitting antenna 0 occupies the Doppler frequency band with a frequency band index of 1, the Doppler frequency of the echo sequence of transmitting antenna 1 occupies the Doppler frequency band with a frequency band index of 2, the Doppler frequency of the echo sequence of transmitting antenna 2 occupies the Doppler frequency band with a frequency band index of 4, and the Doppler frequency of the echo sequence of transmitting antenna 3 occupies the Doppler frequency band with a frequency band index of 8.

[0122] Under this frequency band distribution, when a second moving target appears, the Doppler frequency band that the echo sequence of the moving target may occupy is shown by the diamond in Figure 9. The meaning of the pattern representation in Figure 9 is similar to that of the pattern representation in Figure 5. Please refer to the relevant description of Figure 5 and will not be repeated here. The frequency band crosstalk determined based on Figure 9 is statistically shown in Figure 10. Referring to Figure 10, when one of the two detected targets is stationary and the other is moving, regardless of the speed of the target, the number of overlapping Doppler frequencies of the echo sequences of the two targets will ultimately not exceed one. This effectively controls the amount of frequency band crosstalk when a frequency band offset occurs, thereby reducing the impact of frequency band crosstalk.

[0123] The above describes the signal transmission method of the embodiment of the present application. Corresponding to the above method, the embodiment of the present application also provides a signal transmission device. Figure 11 is a structural diagram of a signal transmission device provided by an embodiment of the present application. Based on the following modules shown in Figure 11, the signal transmission device shown in Figure 11 can perform all or part of the operations shown in the above embodiment. It should be understood that the device may include more additional modules than the modules shown or omit some of the modules shown therein, and the embodiment of the present application is not limited to this. As shown in Figure 11, the device is applied to a transmitting antenna array, and the transmitting antenna array includes W transmitting antennas, W is a positive integer greater than 1, and the device includes:

[0124] Transmitting module 1201, configured to transmit W signal sequences via W transmitting antennas;

[0125] W signal sequences are obtained by modulation using different phases, and the Doppler frequencies corresponding to the W signal sequences are located in W Doppler frequency bands among N equally spaced Doppler frequency bands, where N is a positive integer greater than 1, and N is greater than or equal to W;

[0126] The target periodic autocorrelation sidelobe value λ of the code values ​​of the W Doppler frequency bands is less than or equal to a predefined threshold.

[0127] In one possible implementation, the phase of any signal sequence among the W signal sequences is determined according to the code values ​​of the W Doppler frequency bands and an angle offset value corresponding to any signal sequence, where the angle offset value is obtained by dividing the angle period corresponding to any signal sequence into N equal parts.

[0128] In a possible implementation, N is determined based on the number of signal states indicated by a signal modulation algorithm of the transmit antenna array, where the number of signal states is used to represent the number of signal states modulated by the signal modulation algorithm.

[0129] In one possible implementation, when the number of signal states meets the frequency band requirements corresponding to the transmitting antenna array, N is the number of signal states; or when the number of signal states does not meet the frequency band requirements corresponding to the transmitting antenna array, N is the number of signal states obtained by numerically expanding the number of signal states to meet the frequency band requirements.

[0130] In one possible implementation, the encoding values ​​of the W Doppler frequency bands include W elements assigned a first value and NW elements assigned a second value, one element corresponds to one Doppler frequency band, the first value is used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the second value is used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence, and the first value and the second value are different values.

[0131] In a possible implementation, the predefined threshold is 1.

[0132] In one possible implementation, N is 8 and W is 3, the encoding values ​​of the W Doppler frequency bands are any one of {11010000} and {11000010}, one element of the encoding values ​​of the W Doppler frequency bands corresponds to one Doppler frequency band, 1 is a first value used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and 0 is a second value used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence.

[0133] In one possible implementation, the coding values ​​of the W Doppler frequency bands are {11010000}, and the phases adopted by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 45°, 90°, 135°, 180°, 225°, 270°, 315°], and [0°, 135°, 270°, 45°, 180°, 315°, 90°, 225°].

[0134] In one possible implementation, N is 16 and W is 4, and the encoding values ​​of the W Doppler bands are {1101000100000000}, {1101000000001000}, {110010100000000}, {1100100000010000}, {1100010100000000}, {1100010000000010}, {1100010000000010}, {11000010000000100}, {110000100000001010} 00}, {1100000000100010}, {1100000000010100}, {1011000100000000} and {1011000000001000}, one element of the coded values ​​of the W Doppler frequency bands corresponds to one Doppler frequency band, 1 is a first value used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and 0 is a second value used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence.

[0135] In one possible implementation, the coding values ​​of the W Doppler frequency bands are {1101000100000000}, and the phases used by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, 315°, 325°, 335°, 340°, 350°, 360°, 370°, 380°, 390°, 400°, 410°, 420°, 430°, 440°, 450°, 460°, 470°, 480°, 490°, 500°, 510°, 520°, 530°, 540°, 550°, 560°, 570° , 37.5°], [0°, 67.5°, 135°, 202.5°, 270°, 337.5°, 45°, 112.5°, 180°, 247.5°, 315°, 22.5°, 90°, 157.5°, 225°, 292.5°] and [0°, 157.5°, 315°, 112.5°, 270°, 67.5°, 225°, 22.5°, 180°, 337.5°, 135°, 292.5°, 90°, 247.5°, 45°, 202.5°].

[0136] The target periodic autocorrelation sidelobe value λ of the code values ​​for the W Doppler frequency bands reflects the amount of Doppler frequency overlap between different signal sequences for different targets when multiple targets are present after transmitting the W signal sequences. Because λ is less than or equal to a predefined threshold, the signal transmitter can effectively control the amount of Doppler frequency overlap by transmitting signal sequences using this method, thereby reducing the impact of frequency band crosstalk.

[0137] It should be understood that the device provided in FIG. 11 is merely an example of the division of the functional modules described above when implementing its functions. In actual applications, the functions described above can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the device and method embodiments provided in the above embodiments are based on the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0138] Figure 12 is a structural diagram of a detection device provided in an embodiment of the present application, which may include one or more processors 1401 and one or more memories 1402, wherein at least one computer program is stored in the one or more memories 1402, and the at least one computer program is loaded and executed by the one or more processors 1401. The processor 1401 is, for example, a central processing unit (CPU). Of course, the detection device may also have components such as a wired or wireless network interface, a keyboard, and an input and output interface for input and output. The detection device may also include other components for realizing the functions of the device. For example, the detection device also includes a transmitting antenna array (not shown in Figure 12), and the transmitting antenna array includes W transmitting antennas, and the W transmitting antennas are used to execute the signal transmission method shown above.

[0139] An embodiment of the present application further provides a detection device comprising: a transceiver, a memory, and a processor. The transceiver, the memory, and the processor communicate with each other via an internal connection path. The memory is configured to store instructions, and the processor is configured to execute the instructions stored in the memory to control W transmit antennas included in a transmit antenna array in the transceiver to execute a signal transmission method.

[0140] It should be understood that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor. It is worth noting that the processor may be a processor that supports the Advanced RISC Machine (ARM) architecture.

[0141] Furthermore, in an optional embodiment, the memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. The memory may also include a non-volatile random access memory. For example, the memory may also store device type information.

[0142] The memory may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory may be random access memory (RAM), which is used as an external cache memory. By way of example and not limitation, many forms of RAM are available. For example, static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM) and direct rambus RAM (DR RAM).

[0143] An embodiment of the present application also provides a computer-readable storage medium, in which at least one instruction is stored. The instruction is loaded and executed by a processor, and the processor controls W transmitting antennas in the transmitting antenna array based on a communication connection to implement any of the signal transmission methods described above.

[0144] An embodiment of the present application also provides a computer program (product), including a computer program or instructions, which are executed by a processor to enable a computer to control the W transmitting antennas included in the transmitting antenna array to perform the corresponding steps and / or processes in the above method embodiment.

[0145] An embodiment of the present application also provides a chip, including a processor, for calling and executing instructions stored in the memory from a memory. A communication device equipped with the chip includes a transmitting antenna array, wherein the transmitting antenna array includes W transmitting antennas, and the transmitting antennas are used to execute the above-mentioned signal transmission method.

[0146] An embodiment of the present application also provides another chip, including: an input interface, an output interface, a processor, and a memory, wherein the input interface, the output interface, the processor, and the memory are connected via an internal connection path, and the processor is used to execute the code in the memory. When the code is executed, the processor is used to control the W transmitting antennas included in the transmitting antenna array based on the communication connection to perform any of the signal transmission methods described above.

[0147] An embodiment of the present application further provides a radar system, including a transmitting antenna array, the transmitting antenna array including W transmitting antennas, and the W transmitting antennas are used here to execute any of the signal transmission methods described above.

[0148] An embodiment of the present application further provides a transmitting antenna array, which includes W transmitting antennas, and the W transmitting antennas are used to execute any of the signal transmission methods described above.

[0149] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described herein are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated therein. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive).

Claims

1. A signal transmission method, characterized in that: Applied to a transmitting antenna array, the transmitting antenna array includes W transmitting antennas, where W is a positive integer greater than 1, the method comprising: The W transmitting antennas transmit W signal sequences; The W signal sequences are obtained by modulation using different phases, and the Doppler frequencies corresponding to the W signal sequences are located in W Doppler frequency bands among N equally spaced Doppler frequency bands, where N is a positive integer greater than 1, and N is greater than or equal to W; The target periodic autocorrelation sidelobe value λ of the code values ​​of the W Doppler frequency bands is less than or equal to a predefined threshold.

2. The method according to claim 1, characterized in that The phase of any signal sequence among the W signal sequences is determined according to the code values ​​of the W Doppler frequency bands and an angle offset value corresponding to the any signal sequence, and the angle offset value is obtained by dividing the angle period corresponding to the any signal sequence into N equal parts.

3. The method according to claim 1 or 2, characterized in that The N is determined based on the number of signal states indicated by the signal modulation algorithm of the transmit antenna array, where the number of signal states is used to represent the number of signal states modulated by the signal modulation algorithm.

4. The method according to claim 3, characterized in that When the number of signal states meets the frequency band requirements corresponding to the transmitting antenna array, N is the number of signal states; or when the number of signal states does not meet the frequency band requirements corresponding to the transmitting antenna array, N is the number that meets the frequency band requirements obtained by numerically expanding the number of signal states.

5. The method according to any one of claims 1 to 4, characterized in that: The encoded values ​​of the W Doppler frequency bands include W elements assigned a first value and NW elements assigned a second value, one element corresponds to one Doppler frequency band, the first value is used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the second value is used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence, and the first value and the second value are different values.

6. The method according to any one of claims 1 to 5, characterized in that: The predefined threshold is 1.

7. The method according to claim 6, characterized in that The N is 8 and the W is 3, the coding values ​​of the W Doppler frequency bands are any one of {11010000} and {11000010}, one element in the coding values ​​of the W Doppler frequency bands corresponds to one Doppler frequency band, the 1 is a first value used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the 0 is a second value used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence.

8. The method according to claim 7, characterized in that The coding values ​​of the W Doppler frequency bands are {11010000}, and the phases adopted by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 45°, 90°, 135°, 180°, 225°, 270°, 315°] and [0°, 135°, 270°, 45°, 180°, 315°, 90°, 225°].

9. The method according to claim 6, characterized in that Wherein N is 16 and W is 4, the coding values ​​of the W Doppler frequency bands are {1101000100000000}, {1101000000001000}, {1100101000000000}, {1100100000010000}, {1100010100000000}, {1100010000000010}, {11000100000000100}, {11000010000000100}, {11000010000000100}, {1100001000000010100}, {110 ...10100}, {11000000010100}, {11000000010100}, {11000000010100}, {11000000010100}, {11000 0000000100010}, {1100000000010100}, {1011000100000000} and {1011000000001000}, one element of the coded values ​​of the W Doppler frequency bands corresponds to one Doppler frequency band, the 1 is a first value used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the 0 is a second value used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence.

10. The method according to claim 9, characterized in that The coding values ​​of the W Doppler frequency bands are {1101000100000000}, and the phases adopted by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, 315°, 337.5° °], [0°, 67.5°, 135°, 202.5°, 270°, 337.5°, 45°, 112.5°, 180°, 247.5°, 315°, 22.5°, 90°, 157.5°, 225°, 292.5°] and [0°, 157.5°, 315°, 112.5°, 270°, 67.5°, 225°, 22.5°, 180°, 337.5°, 135°, 292.5°, 90°, 247.5°, 45°, 202.5°].

11. A signal transmitting device, characterized in that: The device is applied to a transmitting antenna array, the transmitting antenna array includes W transmitting antennas, where W is a positive integer greater than 1, and the device includes: A transmitting module, configured to transmit W signal sequences from the W transmitting antennas; The W signal sequences are obtained by modulation using different phases, and the Doppler frequencies corresponding to the W signal sequences are located in W Doppler frequency bands among N equally spaced Doppler frequency bands, where N is a positive integer greater than 1, and N is greater than or equal to W; The target periodic autocorrelation sidelobe value λ of the code values ​​of the W Doppler frequency bands is less than or equal to a predefined threshold.

12. The device according to claim 11, characterized in that The phase of any signal sequence among the W signal sequences is determined according to the code values ​​of the W Doppler frequency bands and an angle offset value corresponding to the any signal sequence, and the angle offset value is obtained by dividing the angle period corresponding to the any signal sequence into N equal parts.

13. The device according to claim 11 or 12, characterized in that The N is determined based on the number of signal states indicated by the signal modulation algorithm of the transmit antenna array, where the number of signal states is used to represent the number of signal states modulated by the signal modulation algorithm.

14. The device according to claim 13, characterized in that When the number of signal states meets the frequency band requirements corresponding to the transmitting antenna array, N is the number of signal states; or when the number of signal states does not meet the frequency band requirements corresponding to the transmitting antenna array, N is the number that meets the frequency band requirements obtained by numerically expanding the number of signal states.

15. The device according to any one of claims 11 to 14, characterized in that: The encoded values ​​of the W Doppler frequency bands include W elements assigned a first value and NW elements assigned a second value, one element corresponds to one Doppler frequency band, the first value is used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the second value is used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence, and the first value and the second value are different values.

16. The device according to any one of claims 11 to 15, characterized in that: The predefined threshold is 1.

17. The device according to claim 16, characterized in that The N is 8 and the W is 3, the coding values ​​of the W Doppler frequency bands are any one of {11010000} and {11000010}, one element in the coding values ​​of the W Doppler frequency bands corresponds to one Doppler frequency band, the 1 is a first value used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the 0 is a second value used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence.

18. The device according to claim 17, characterized in that The coding values ​​of the W Doppler frequency bands are {11010000}, and the phases adopted by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 45°, 90°, 135°, 180°, 225°, 270°, 315°] and [0°, 135°, 270°, 45°, 180°, 315°, 90°, 225°].

19. The device according to claim 16, characterized in that Wherein N is 16 and W is 4, the coding values ​​of the W Doppler frequency bands are {1101000100000000}, {1101000000001000}, {1100101000000000}, {1100100000010000}, {1100010100000000}, {1100010000000010}, {11000100000000100}, {11000010000000100}, {11000010000000100}, {1100001000000010100}, {110 ...10100}, {11000000010100}, {11000000010100}, {11000000010100}, {11000000010100}, {11000 0000000100010}, {1100000000010100}, {1011000100000000} and {1011000000001000}, one element of the coded values ​​of the W Doppler frequency bands corresponds to one Doppler frequency band, the 1 is a first value used to indicate that the corresponding Doppler frequency band is occupied by the Doppler frequency corresponding to the signal sequence, and the 0 is a second value used to indicate that the corresponding Doppler frequency band is not occupied by the Doppler frequency corresponding to the signal sequence.

20. The device according to claim 19, characterized in that The coding values ​​of the W Doppler frequency bands are {1101000100000000}, and the phases adopted by the W signal sequences are [0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°, 0°], [0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, 157.5°, 180°, 202.5°, 225°, 247.5°, 270°, 292.5°, 315°, 337.5° °], [0°, 67.5°, 135°, 202.5°, 270°, 337.5°, 45°, 112.5°, 180°, 247.5°, 315°, 22.5°, 90°, 157.5°, 225°, 292.5°] and [0°, 157.5°, 315°, 112.5°, 270°, 67.5°, 225°, 22.5°, 180°, 337.5°, 135°, 292.5°, 90°, 247.5°, 45°, 202.5°].

21. A transmitting antenna array, characterized in that: The transmitting antenna array includes W transmitting antennas; the transmitting antennas are used to implement the signal transmitting method described in any one of claims 1-10.

22. A radar system, characterized in that: The radar system includes a transmitting antenna array, which includes W transmitting antennas. The transmitting antennas are used to implement the signal transmission method according to any one of claims 1 to 10.

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