A design method and device for multi-frequency waveform in a pulse

Abstract

The present invention provides a design method and device for an intra-pulse multi-frequency waveform, wherein a plurality of single-frequency sub-pulses are sent to a target within each preset pulse period, and the carrier frequency of the single-frequency sub-pulses within the same preset pulse period is uniformly increased in a preset frequency step according to a coding order; a total echo signal corresponding to each preset pulse period from the target is received in a time sequence, and the frequency points corresponding to each sub-pulse echo in each preset pulse period are obtained according to the total echo signal corresponding to each preset pulse period; the phase difference between adjacent sub-pulse echoes is obtained according to the frequency points corresponding to each sub-pulse echo in each preset pulse period; the target distance corresponding to each preset pulse period is obtained according to the phase difference between adjacent sub-pulse echoes; and discrete intra-frequency single-frequency sub-pulses are used as detection signals, thereby avoiding the angle steering vector and the Doppler steering vector from affecting the acquisition of the target distance during the calculation process.

Description

Technical Field

[0001] The present invention relates to the technical field of signal processing, and in particular to a design method and device for a multi-frequency waveform within a pulse. Background Art

[0002] The detection system can detect and locate targets in various fields such as air, sea, and land all day and all weather. In the detection system, linear frequency modulation signals play a very important role. The time-bandwidth product of this pulse compression signal is large, which can improve the range and resolution of the detection system while ensuring the signal energy. However, with the advancement of science and technology, the interference technology for linear frequency modulation signals has flourished, especially with the emergence of digital radio frequency memory. Various interferences such as frequency shift interference, forwarding interference, and intermittent sampling forwarding interference are coherent with the detection signal, which can also obtain the energy gain of pulse compression. After being processed by the detection system, a false target with strong energy is generated, which brings a strong interference effect to the detection ability of the detection system.

[0003] Numerous studies have shown that frequency domain discretization will bring about distance-guided vectors. According to the phase difference between distance-guided vectors, the real distance information between the detection system and the target can be obtained, thereby improving the anti-interference ability of the detection system. However, frequency domain discretization mostly uses array element signals or pulse signals. The resulting problem is that when array element signals or pulse signals are used for detection, angle-guided vectors or Doppler-guided vectors will be introduced in the calculation process, and the distance-guided vector will be coupled with the angle-guided vector or Doppler-guided vector, affecting the acquisition of the distance-guided vector.

[0004] In view of this, overcoming the defects of the prior art is an urgent problem to be solved in the field of this technology. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to accurately obtain distance information from the detection signal in a discrete form in the frequency domain.

[0006] The present invention adopts the following technical solution:

[0007] In a first aspect, a method for designing a multi-frequency waveform within a pulse is provided, comprising:

[0008] Sending a preset number of single-frequency sub-pulses to the target in each preset pulse period, and encoding each single-frequency sub-pulse in each preset pulse period, wherein the carrier frequency of the single-frequency sub-pulses in the same preset pulse period is uniformly increased in steps of a preset frequency according to the coding order;

[0009] Receive a total echo signal corresponding to each preset pulse period from the target in a time sequence, and obtain a frequency point corresponding to each sub-pulse echo in each preset pulse period according to the total echo signal corresponding to each preset pulse period;

[0010] Obtaining the phase difference between adjacent sub-pulse echoes according to the frequency points corresponding to each sub-pulse echo in each preset pulse period;

[0011] The target distance corresponding to each preset pulse period is obtained according to the phase difference between adjacent sub-pulse echoes.

[0012] Preferably, encoding each single-frequency sub-pulse within each preset pulse period specifically includes:

[0013] The encoding expression of each single frequency sub-pulse in each preset pulse period is:

[0014] ;

[0015] in, is the coding expression of the mth single frequency sub-pulse, A is the signal amplitude, is the carrier frequency of the mth single-frequency pulse, , is the carrier frequency of the first single-frequency pulse in the preset pulse period, is the frequency step between single frequency point pulses, , t is the discretized fast time variable.

[0016] Preferably, the receiving, in a time sequence, a total echo signal corresponding to each preset pulse period from the target specifically includes:

[0017] The expression of the total echo signal corresponding to each preset pulse period is:

[0018] ;

[0019] in, is the total echo signal, is the echo amplitude, c is the speed of light, , t is the discretized fast time variable, R is the target distance, is the carrier frequency of the first single-frequency pulse, is the carrier frequency of the second single-frequency pulse, is the carrier frequency of the Mth single-frequency sub-pulse, and M is the number of single-frequency sub-pulses in a single preset pulse period.

[0020] Preferably, the receiving of the total echo signal corresponding to each preset pulse period from the target in a time sequence order further includes:

[0021] The received total echo signal is subjected to coherent accumulation processing, and all the total echo signals are accumulated and amplified in the dimensions of all preset pulse periods through the coherent accumulation processing, thereby improving the signal-to-noise ratio of the total echo signal.

[0022] Preferably, the acquiring, according to the total echo signal corresponding to each preset pulse period, the frequency points corresponding to each sub-pulse echo in each preset pulse period specifically includes:

[0023] Segmenting the total echo signal according to the coding length of each single-frequency sub-pulse in a preset pulse period to obtain each sub-pulse echo in the total echo signal;

[0024] Performing Fourier transform on each sub-pulse echo in the total echo signal to obtain a frequency spectrum corresponding to each sub-pulse echo in a preset pulse period;

[0025] The peak value in the frequency spectrum corresponding to each sub-pulse echo is taken as the frequency point corresponding to each sub-pulse echo.

[0026] Preferably, the expression of the signal sequence of the frequency points corresponding to all sub-pulse echoes in each preset pulse period is:

[0027] ;

[0028] in, is the echo amplitude after Fourier transformation, is the impulse function, is the carrier frequency of the first single-frequency pulse in the preset pulse period, is the frequency step between single-frequency pulses, c is the speed of light, , R is the target distance, and M is the number of single-frequency sub-pulses in a single preset pulse cycle.

[0029] Preferably, the acquiring the phase difference between adjacent sub-pulse echoes according to the frequency points corresponding to the sub-pulse echoes in each preset pulse period specifically includes:

[0030] Perform Fourier transform on the signal sequence of the frequency points corresponding to all sub-pulse echoes in each preset pulse period to obtain the spectrum corresponding to the signal sequence. The spectrum corresponding to the signal sequence is expressed as:

[0031] ;

[0032] in, is the characteristic frequency after Fourier transform of the signal sequence, is the echo amplitude after Fourier transform of the signal sequence, is the symplectic function;

[0033] A peak value in the frequency spectrum corresponding to the signal sequence is acquired, and the peak value in the frequency spectrum corresponding to the signal sequence is used as the phase difference between adjacent sub-pulse echoes.

[0034] Preferably, the step of obtaining the target distance corresponding to each preset pulse period according to the phase difference between adjacent sub-pulse echoes specifically includes:

[0035] The expression corresponding to the target distance is:

[0036] ;

[0037] Where R is the target distance, c is the speed of light, is the phase difference between adjacent sub-pulse echoes, It is the frequency step between single frequency point pulses.

[0038] In a second aspect, a device for designing a multi-frequency waveform within a pulse is provided, comprising at least one processor and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor to execute the method for designing a multi-frequency waveform within a pulse.

[0039] In a third aspect, the present invention further provides a non-volatile computer storage medium, wherein the computer storage medium stores computer executable instructions, and the computer executable instructions are executed by one or more processors to complete the method described in the first aspect.

[0040] In a fourth aspect, a chip is provided, comprising: a processor and an interface, for calling and running a computer program stored in the memory from a memory to execute the method of the first aspect.

[0041] In a fifth aspect, a computer program product comprising instructions is provided, which, when executed on a computer or a processor, causes the computer or the processor to execute the method of the first aspect.

[0042] In a sixth aspect, a system for designing a multi-frequency waveform within a pulse is provided, comprising a design device for a multi-frequency waveform within a pulse as in the second aspect, and using a design method for a multi-frequency waveform within a pulse as in the first aspect.

[0043] The present invention provides a design method and device for an intra-pulse multi-frequency waveform, wherein a plurality of single-frequency sub-pulses are sent to a target within each preset pulse period, and the carrier frequency of the single-frequency sub-pulses within the same preset pulse period is uniformly increased in a preset frequency step according to a coding order; a total echo signal corresponding to each preset pulse period from the target is received in a time sequence, and the frequency points corresponding to each sub-pulse echo in each preset pulse period are obtained according to the total echo signal corresponding to each preset pulse period; the phase difference between adjacent sub-pulse echoes is obtained according to the frequency points corresponding to each sub-pulse echo in each preset pulse period; the target distance corresponding to each preset pulse period is obtained according to the phase difference between adjacent sub-pulse echoes; and discrete intra-frequency single-frequency sub-pulses are used as detection signals, thereby avoiding the angle steering vector and the Doppler steering vector from affecting the acquisition of the target distance during the calculation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0045] Figure 1 It is a method flow chart of a method for designing a multi-frequency waveform within a pulse provided by an embodiment of the present invention;

[0046] Figure 2 It is a flow chart of a method for obtaining the frequency of each sub-pulse echo in a method for designing a multi-frequency waveform within a pulse provided by an embodiment of the present invention;

[0047] Figure 3 It is a method flow chart of whether coherent accumulation processing is required in a method for designing a multi-frequency waveform within a pulse provided by an embodiment of the present invention;

[0048] Figure 4 It is a flow chart of a method for obtaining the phase difference between adjacent sub-pulse echoes in a method for designing a multi-frequency waveform within a pulse provided by an embodiment of the present invention;

[0049] Figure 5 It is a schematic diagram of a device for designing a multi-frequency waveform within a pulse provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0051] In the description of the present invention, the terms "inside", "outside", "longitudinal", "lateral", "upper", "lower", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0052] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0053] Embodiment 1:

[0054] Embodiment 1 of the present invention provides a method for designing a multi-frequency waveform within a pulse. Figure 1 As shown, including:

[0055] In step 101, a preset number of single-frequency sub-pulses are sent to the target in each preset pulse period, and each single-frequency sub-pulse in each preset pulse period is encoded, wherein the carrier frequency of the single-frequency sub-pulses in the same preset pulse period is uniformly increased in steps of a preset frequency according to the encoding order.

[0056] In this embodiment, a detection signal is transmitted to a certain range of the outside world through a detection system. The transmission form of the detection signal is to send a preset number of single-frequency sub-pulses for each preset pulse period. The preset pulse period is set by technical personnel in this field, and the preset number is set by technical personnel in this field according to actual conditions. The frequencies corresponding to the single-frequency sub-pulses in the same preset pulse period are discrete from each other, and the single-frequency sub-pulses in different preset pulse periods are represented by corresponding expressions to implement corresponding encoding and use for subsequent calculations. At the same time, the carrier frequency of the single-frequency sub-pulses in each preset pulse period is uniformly increased in preset frequency steps, and the order of increase is the encoding order of each single-frequency sub-pulse. The preset frequency step is set by technical personnel in this field according to actual conditions.

[0057] In this embodiment, the reason for using multiple single-frequency sub-pulses in the same preset pulse period is that if conventional multiple discrete pulse signals are used as detection signals to be sent to the target, and the target distance between the target and the detection system is obtained by receiving the echo signal from the target, the target distance between the target and the detection system is calculated based on the fixed phase difference between adjacent pulse echoes. The Doppler steering vector will be mixed with the value of the target distance, resulting in the inability to obtain the corresponding target distance. Similarly, if the array element signal is used as the detection signal to be sent to the target, and the target distance between the target and the detection system is obtained by receiving the echo signal from the target, when calculating the target distance, the angle steering vector will be coupled with the target distance, and the target distance cannot be obtained. In the present embodiment, firstly, the array element signal is not used as the detection signal, thereby avoiding the problem caused by the angle steering vector in the calculation process, and since multiple single-frequency point pulses are sent within a single preset pulse period, there is no frequency stepping between the pulses in different preset pulse periods, and therefore the received echo signal will not generate a Doppler frequency, and the Doppler steering vector and the target distance will not be mixed together in the calculation process. However, since there is a frequency stepping between the single-frequency point pulses within the same preset pulse period, there is a fixed phase difference between the single-frequency point pulses, and the distance between the target and the detection system can also be obtained through the fixed phase difference, and it will not be affected by the Doppler frequency.

[0058] In step 102, a total echo signal corresponding to each preset pulse period from the target is received in a time sequence, and a frequency point corresponding to each sub-pulse echo in each preset pulse period is obtained according to the total echo signal corresponding to each preset pulse period.

[0059] In the present embodiment, the total echo signal corresponding to each preset pulse period includes a preset number of sub-pulse echoes (the sub-pulse echo is the echo reflected from the target corresponding to each single-frequency sub-pulse). Since the coding length of each sub-pulse echo received by the detection system after the single-frequency sub-pulse is reflected back to the detection system through the target is consistent with the original length of the corresponding single-frequency sub-pulse. Therefore, the total echo signal corresponding to the preset pulse period can be segmented according to the coding length of each single-frequency sub-pulse, so as to obtain the sub-pulse echo corresponding to each single-frequency sub-pulse in the total echo signal. Then, each sub-pulse echo is subjected to Fourier transform to obtain the frequency spectrum of each sub-pulse echo, so as to obtain the frequency point corresponding to each sub-pulse echo, which is used for subsequent calculation of the target distance.

[0060] In step 103, the phase difference between adjacent sub-pulse echoes is obtained according to the frequency points corresponding to the sub-pulse echoes in each preset pulse period.

[0061] In step 104, the target distance corresponding to each preset pulse period is obtained according to the phase corresponding to each sub-pulse echo in each preset pulse period.

[0062] Furthermore, since the frequency steps between adjacent sub-pulse echoes are consistent, the phase differences between adjacent sub-pulse echoes are consistent. The frequency points of each sub-pulse echo obtained can be used as a signal sequence to obtain the characteristic frequency of the corresponding signal sequence. The characteristic frequency is the phase difference between adjacent sub-pulse echoes. When the frequency step between single-frequency sub-pulses is fixed, the phase difference between adjacent sub-pulse echoes is related to the target distance. Therefore, the target distance can be obtained by the phase difference between adjacent sub-pulse echoes to complete the detection signal task.

[0063] In summary, in this embodiment, by sending single-frequency point pulses with the same frequency step to the target within each preset pulse period, the detection system completes frequency sampling within each preset pulse period. Since there is no frequency step between pulses between different preset pulse periods and array element signals are not used for detection, the interference of Doppler steering vectors or angle steering vectors will not be introduced in the calculation process, thereby achieving accurate acquisition of the target distance between the detection system and the target.

[0064] Furthermore, when the detection signal is actually sent to the target through the detection system, the pulse train emitted in each preset pulse period includes multiple discrete single-frequency sub-pulses. In order to facilitate subsequent calculations, each single-frequency sub-pulse needs to be encoded, so the corresponding encoding expression is:

[0065] The encoding of each single-frequency sub-pulse in each preset pulse period specifically includes: the encoding expression of each single-frequency sub-pulse in each preset pulse period is:

[0066] ;

[0067] in, is the coding expression of the mth single frequency sub-pulse, A is the signal amplitude, is the carrier frequency of the mth single-frequency pulse, , is the carrier frequency of the first single-frequency pulse in the preset pulse period, is the frequency step between single frequency point pulses, , t is the discretized fast time variable.

[0068] Furthermore, the expression of the pulse train sent by a single preset pulse period is:

[0069] ;

[0070] in, is the encoding expression of the first single-frequency sub-pulse, is the encoding expression of the second single frequency sub-pulse, is the coding expression of the Mth single-frequency sub-pulse, where M is the preset number, that is, the number of single-frequency sub-pulses in a single preset pulse period.

[0071] Further, according to the coding expression of each encoded single-frequency sub-pulse, the expression of the sub-pulse echo reflected from the target by each single-frequency sub-pulse can be obtained, thereby obtaining the expression of the total echo signal. Therefore, this embodiment also involves the following design:

[0072] The receiving, in a time sequence, a total echo signal corresponding to each preset pulse period from the target specifically includes: the expression of the total echo signal corresponding to each preset pulse period is:

[0073] ;

[0074] in, is the total echo signal, is the first sub-pulse echo within the preset pulse period, is the first sub-pulse echo within the preset pulse period, It is the first sub-pulse echo within the preset pulse period.

[0075] Correspondingly, the expression of the encoding of each single-frequency sub-pulse within the preset pulse period is substituted into the above formula to obtain:

[0076] ;

[0077] in, is the total echo signal, is the echo amplitude, c is the speed of light, , t is the discretized fast time variable, R is the target distance, is the carrier frequency of the first single-frequency pulse, is the carrier frequency of the second single-frequency pulse, is the carrier frequency of the Mth single-frequency sub-pulse, and M is the number of single-frequency sub-pulses in a single preset pulse period.

[0078] It is worth mentioning that after receiving the total echo signal, it is necessary to perform Fourier transform on each sub-pulse echo in the total echo signal to obtain the corresponding spectrum, and confirm the frequency point corresponding to the sub-pulse echo according to the peak position in the spectrum. However, the problem is that when the target object is too far away from the detection system, or the target object imposes a certain counter-interference on the total echo signal, there are a large number of interference signals and noise signals in the total echo signal received by the detection system, and when the target is far away from the detection system, the signal energy in a single preset pulse period is usually weak, and the total echo signal of a single preset pulse period or a small number of preset pulses cannot be used to detect the total echo signal. It is difficult to obtain the effective signal in the total echo signal of the pulse period. In this state, if the total echo signal is directly subjected to Fourier transformation to obtain the corresponding spectrum, the effective signal will be buried by the noise signal and / or the interference signal, and the accurate frequency point cannot be obtained. Therefore, it is necessary to accumulate the total echo signals of multiple different preset pulse periods, so that the energy of the effective signal becomes larger and larger through accumulation, and the signal-to-noise ratio is improved at the same time, so as to ensure that the effective signal in the total echo signal can be accurately obtained. Therefore, this embodiment also involves the following design: the total echo signal corresponding to each preset pulse period from the target is received in a time sequence, and also includes:

[0079] The received total echo signal is subjected to coherent accumulation processing, and all the total echo signals are accumulated and amplified in the dimensions of all preset pulse periods through the coherent accumulation processing, thereby improving the signal-to-noise ratio of the total echo signal.

[0080] It is worth mentioning that if the target object is close to the detection system and the target object itself does not interfere with the detection signal, there will be fewer interference signals and noise signals in the total echo signal. At the same time, the energy of the received total echo signal is sufficient and will not affect the acquisition of the frequency points of each sub-pulse echo. In this case, there is no need to perform coherent accumulation processing on the received total echo signal.

[0081] Further, after receiving the total echo signal, each sub-pulse echo in the total echo signal can be processed to obtain the spectrum and frequency point corresponding to each sub-pulse echo. Specifically, this embodiment involves the following design:

[0082] According to the total echo signal corresponding to each preset pulse period, the frequency points corresponding to each sub-pulse echo in each preset pulse period are obtained, such as Figure 2 As shown, the method flow includes:

[0083] In step 201, the total echo signal is segmented according to the coding length of each single-frequency sub-pulse in a preset pulse period to obtain each sub-pulse echo in the total echo signal.

[0084] In step 202, Fourier transform is performed on each sub-pulse echo in the total echo signal to obtain a frequency spectrum corresponding to each sub-pulse echo in a preset pulse period.

[0085] Correspondingly, in this embodiment, the expression corresponding to the spectrum corresponding to each sub-pulse echo in the preset pulse period can be:

[0086] ;

[0087] in, is the Fourier transform, is the echo amplitude after Fourier transformation, is the impulse function, is the carrier frequency of the first single-frequency pulse, is the carrier frequency of the second single-frequency pulse, is the carrier frequency of the Mth single-frequency pulse, M is the number of single-frequency pulses in a single preset pulse cycle, c is the speed of light, , R is the target distance.

[0088] In step 203, the peak value in the frequency spectrum corresponding to each sub-pulse echo is used as the frequency point corresponding to each sub-pulse echo.

[0089] After obtaining the spectrum corresponding to each sub-pulse echo, obtain the peak value on the spectrum corresponding to each sub-pulse echo. The peak position is the frequency point corresponding to the corresponding sub-pulse echo. In order to obtain the phase difference between each sub-pulse echo, the frequency point corresponding to each sub-pulse echo needs to be used as a signal sequence and perform a second Fourier transform. Therefore, the expression of the signal sequence of the frequency points corresponding to all sub-pulse echoes in each preset pulse period is:

[0090] ;

[0091] in, is the echo amplitude after Fourier transformation, is the impulse function, is the carrier frequency of the first single-frequency pulse in the preset pulse period, is the frequency step between single-frequency pulses, c is the speed of light, , R is the target distance, is the carrier frequency of the first single-frequency pulse, is the carrier frequency of the second single-frequency pulse, is the carrier frequency of the Mth single-frequency sub-pulse, M is the number of single-frequency sub-pulses in a single preset pulse period; (0:M-1) refers to the frequency corresponding to the 1st sub-pulse echo to the frequency corresponding to the Mth sub-pulse echo.

[0092] Combined with the above coherent accumulation processing, after receiving the total echo signal and performing Fourier transform to obtain the spectrum, it can be determined whether coherent accumulation processing is required based on the spectrum, such as Figure 3 As shown, the judgment method process includes:

[0093] In step 301, Fourier transform is performed on each sub-pulse echo in the total echo signal to obtain a frequency spectrum corresponding to each sub-pulse echo in a preset pulse period.

[0094] In step 302, it is determined whether the peaks in each spectrum are interfered with. If the peaks in the spectrum are interfered with, the total echo signals of each preset pulse period are coherently accumulated. If the peaks in the spectrum are not interfered with, the peaks in each spectrum are directly obtained and used as the frequency points of the corresponding sub-pulse echoes.

[0095] Furthermore, after obtaining the signal sequence of the frequency points corresponding to each sub-pulse echo, the signal sequence can be Fourier transformed to obtain the frequency spectrum corresponding to the signal sequence, and then the phase difference between adjacent sub-pulse echoes can be obtained according to the frequency spectrum corresponding to the signal sequence, such as Figure 4 As shown, the method flow includes:

[0096] In step 401, the frequency points of the sub-pulse echoes obtained within the preset pulse period are used as a signal sequence.

[0097] In step 402, Fourier transform is performed on the signal sequence to obtain a frequency spectrum corresponding to the signal sequence.

[0098] In step 403, the peak value in the frequency spectrum corresponding to the signal sequence is used as the phase difference between adjacent sub-pulse echoes.

[0099] Perform Fourier transform on the signal sequence of the frequency points corresponding to all sub-pulse echoes in each preset pulse period to obtain the spectrum corresponding to the signal sequence. The spectrum corresponding to the signal sequence is expressed as:

[0100] ;

[0101] in, is the characteristic frequency after Fourier transform of the signal sequence, is the echo amplitude after Fourier transform of the signal sequence, is the Symgine function.

[0102] A peak value in the frequency spectrum corresponding to the signal sequence is acquired, and the peak value in the frequency spectrum corresponding to the signal sequence is used as the phase difference between adjacent sub-pulse echoes.

[0103] After the phase difference between adjacent sub-pulse echoes is obtained, the target distance between the detection system and the target object can be obtained according to the phase difference, which specifically includes:

[0104] The expression corresponding to the target distance is:

[0105] ;

[0106] Where R is the target distance, c is the speed of light, is the phase difference between adjacent sub-pulse echoes, It is the frequency step between single frequency point pulses.

[0107] In summary, this embodiment designs multi-frequency sub-pulses in a preset pulse period to allow the detection signal to complete frequency domain sampling in the preset pulse period, and uses frequency domain sampling to obtain information on the target distance. The target distance information is not easily interfered with, thereby improving the anti-interference capability of the detection system; at the same time, it avoids the confusion between the angle steering vector and the Doppler steering vector and the target distance value, reduces the complexity of implementation, and makes up for the shortcomings of the existing method.

[0108] Embodiment 2:

[0109] like Figure 5 , which is a schematic diagram of a device for designing a multi-frequency waveform in a pulse according to an embodiment of the present invention. The device for designing a multi-frequency waveform in a pulse according to this embodiment includes one or more processors 41 and a memory 42.

[0110] The processor 41 and the memory 42 may be connected via a bus or other means. Figure 5 The example of connecting through bus is taken in the following.

[0111] The memory 42 is a non-volatile computer-readable storage medium that can be used to store non-volatile software programs and non-volatile computer executable programs, such as the method for designing a multi-frequency waveform within a pulse in the above embodiment. The processor 41 executes the method for designing a multi-frequency waveform within a pulse by running the non-volatile software programs and instructions stored in the memory 42.

[0112] The memory 42 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage devices. In some embodiments, the memory 42 may optionally include a memory remotely arranged relative to the processor 41, and these remote memories may be connected to the processor 41 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0113] The program instructions / modules are stored in the memory 42, and when executed by the one or more processors 41, the design method of the multi-frequency waveform in the pulse in the above embodiment is executed, for example, the above described Figure 1-Figure 4 The steps shown.

[0114] An embodiment of the present invention further provides a computer storage medium having computer program instructions stored thereon; when the computer program instructions are executed by a processor, the method for designing a multi-frequency waveform within a pulse provided by an embodiment of the present invention is implemented.

[0115] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for designing a multi-frequency waveform within a pulse, characterized in that: include: Sending a preset number of single-frequency sub-pulses to the target in each preset pulse period, and encoding each single-frequency sub-pulse in each preset pulse period, wherein the carrier frequency of the single-frequency sub-pulses in the same preset pulse period is uniformly increased in steps of a preset frequency according to the coding order; Receive a total echo signal corresponding to each preset pulse period from the target in a time sequence, and obtain a frequency point corresponding to each sub-pulse echo in each preset pulse period according to the total echo signal corresponding to each preset pulse period; Obtaining the phase difference between adjacent sub-pulse echoes according to the frequency points corresponding to each sub-pulse echo in each preset pulse period; The target distance corresponding to each preset pulse period is obtained according to the phase difference between adjacent sub-pulse echoes.

2. The method for designing a multi-frequency waveform in a pulse according to claim 1, characterized in that: The encoding of each single-frequency sub-pulse within each preset pulse period specifically includes: The encoding expression of each single frequency sub-pulse in each preset pulse period is: ； in, is the coding expression of the mth single frequency sub-pulse, A is the signal amplitude, is the carrier frequency of the mth single-frequency pulse, , is the carrier frequency of the first single-frequency pulse in the preset pulse period, is the frequency step between single frequency point pulses, , t is the discretized fast time variable.

3. The method for designing a multi-frequency waveform in a pulse according to claim 1, characterized in that: The receiving, in a time sequence, a total echo signal corresponding to each preset pulse period from the target specifically includes: The expression of the total echo signal corresponding to each preset pulse period is: ； in, is the total echo signal, is the echo amplitude, c is the speed of light, , t is the discretized fast time variable, R is the target distance, is the carrier frequency of the first single-frequency pulse, is the carrier frequency of the second single-frequency pulse, is the carrier frequency of the Mth single-frequency sub-pulse, and M is the number of single-frequency sub-pulses in a single preset pulse period.

4. The method for designing a multi-frequency waveform in a pulse according to claim 1, characterized in that: The receiving, in a time sequence, a total echo signal corresponding to each preset pulse period from the target also includes: The received total echo signal is subjected to coherent accumulation processing, and all the total echo signals are accumulated and amplified in the dimensions of all preset pulse periods through the coherent accumulation processing, thereby improving the signal-to-noise ratio of the total echo signal.

5. The method for designing a multi-frequency waveform in a pulse according to claim 1, characterized in that: The acquiring, according to the total echo signal corresponding to each preset pulse period, the frequency points corresponding to each sub-pulse echo in each preset pulse period specifically includes: Segmenting the total echo signal according to the coding length of each single-frequency sub-pulse in a preset pulse period to obtain each sub-pulse echo in the total echo signal; Performing Fourier transform on each sub-pulse echo in the total echo signal to obtain a frequency spectrum corresponding to each sub-pulse echo in a preset pulse period; The peak value in the frequency spectrum corresponding to each sub-pulse echo is taken as the frequency point corresponding to each sub-pulse echo.

6. The method for designing a multi-frequency waveform in a pulse according to claim 5, characterized in that: The expression of the signal sequence of the frequency points corresponding to all sub-pulse echoes in each preset pulse period is: ； in, is the echo amplitude after Fourier transformation, is the impulse function, is the carrier frequency of the first single-frequency pulse in the preset pulse period, is the frequency step between single-frequency pulses, c is the speed of light, , R is the target distance, and M is the number of single-frequency sub-pulses in a single preset pulse cycle.

7. The method for designing a multi-frequency waveform in a pulse according to claim 6, characterized in that: The acquiring the phase difference between adjacent sub-pulse echoes according to the frequency points corresponding to each sub-pulse echo in each preset pulse period specifically includes: Perform Fourier transform on the signal sequence of the frequency points corresponding to all sub-pulse echoes in each preset pulse period to obtain the spectrum corresponding to the signal sequence. The spectrum corresponding to the signal sequence is expressed as: ； in, is the characteristic frequency after Fourier transform of the signal sequence, is the echo amplitude after Fourier transform of the signal sequence, is the symplectic function; A peak value in the frequency spectrum corresponding to the signal sequence is acquired, and the peak value in the frequency spectrum corresponding to the signal sequence is used as the phase difference between adjacent sub-pulse echoes.

8. The method for designing a multi-frequency waveform in a pulse according to claim 7, characterized in that: The step of obtaining the target distance corresponding to each preset pulse period according to the phase difference between adjacent sub-pulse echoes specifically includes: The expression corresponding to the target distance is: ； Where R is the target distance, c is the speed of light, is the phase difference between adjacent sub-pulse echoes, It is the frequency step between single frequency point pulses.

9. A device for designing a multi-frequency waveform within a pulse, characterized in that: It includes at least one processor and a memory that is communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the processor to execute the method for designing a multi-frequency waveform within a pulse according to any one of claims 1-8.

10. A non-volatile computer storage medium, characterized in that: The computer storage medium stores computer program instructions, which, when executed by one or more processors, implement the method for designing a multi-frequency waveform within a pulse as described in any one of claims 1-8.

Images