CN114609606B

CN114609606B - Parameter estimation method and device of target object and electronic equipment

Info

Publication number: CN114609606B
Application number: CN202210511709.2A
Authority: CN
Inventors: 李锋林; 赵海军; 项喆; 李存勖; 王卫国
Original assignee: Esso Information Co ltd
Current assignee: Esso Information Co ltd
Priority date: 2022-05-12
Filing date: 2022-05-12
Publication date: 2022-09-23
Anticipated expiration: 2042-05-12
Also published as: CN114609606A

Abstract

The application provides a parameter estimation method and device of a target object and electronic equipment, and belongs to the technical field of radar signal processing. The method comprises the following steps: receiving an echo signal returned by a target object, and converting the echo signal into a distance frequency-slow time domain along a fast time dimension to obtain a target signal; correcting the multi-order distance walking and multi-order Doppler walking of the target signal to obtain a corrected signal; performing coherent accumulation processing on the corrected signal along the distance frequency and the slow time dimension of the distance frequency-slow time domain respectively to obtain a first coherent accumulation result; estimating a first parameter of the target object according to the first coherent accumulation result, wherein the first parameter comprises acceleration and jerk of the target object. The method and the device can achieve the effect of improving the accuracy of parameter estimation of the target object.

Description

Parameter estimation method and device of target object and electronic equipment

Technical Field

The application relates to the technical field of radar signal processing, in particular to a method and a device for estimating parameters of a target object and electronic equipment.

Background

With the development of scientific technology, people start to use radar technology to realize functions of target detection, tracking and the like, which requires estimation of parameters of targets.

Generally, when parameter estimation is performed by a radar, a long-time coherent accumulation mode is adopted, and motion information and doppler information of a target are acquired by using detection information of a range cell of the radar, so as to estimate parameter information of the target. However, with the increasing speed of modern aircraft, and the variable speed movement of these aircraft in general, it is likely that the aircraft will span multiple distance units in a short period of time.

However, in the case of detecting and tracking an object by using a long-time coherent accumulation method, if the object spans a plurality of range bins in a short time, the distance is moved, and thus, this scheme has a problem that the parameter estimation of a high-speed object is inaccurate.

Disclosure of Invention

The application aims to provide a method and a device for estimating parameters of a target object and electronic equipment, which can achieve the effect of improving the accuracy of parameter estimation of the target object.

The embodiment of the application is realized as follows:

in a first aspect of the embodiments of the present application, a method for estimating parameters of a target object is provided, where the method includes:

receiving an echo signal returned by a target object, and converting the echo signal into a distance frequency-slow time domain along a fast time dimension to obtain a target signal;

correcting the multi-order distance walking and the multi-order Doppler walking of the target signal to obtain a corrected signal, wherein the multi-order distance walking comprises first-order distance walking, second-order distance walking and third-order distance walking, the multi-order Doppler walking comprises second-order Doppler walking and third-order Doppler walking, and the third-order distance walking and the third-order Doppler walking are generated by the jerk of the target object;

performing coherent accumulation processing on the corrected signal along the distance frequency and the slow time dimension of the distance frequency-slow time domain respectively to obtain a first coherent accumulation result;

and estimating a first parameter of the target object according to the first coherent accumulation result, wherein the first parameter comprises the acceleration and the jerk of the target object.

Optionally, the performing a correction process on the multi-step range walk and the multi-step doppler walk of the target signal to obtain a corrected signal includes:

correcting for third order range walk of the target signal resulting from jerk of the target object;

correcting for third order doppler walk of the target signal resulting from jerk of the target object by constructing a first compensation function;

correcting second-order range walk and second-order Doppler walk of the target signal generated by the acceleration of the target object, and correcting first-order range walk of the target signal generated by the velocity of the target object, to obtain the corrected signal.

Optionally, the correcting for third order distance walk of the target signal resulting from jerk of the target object comprises:

and carrying out third-order keystone-shaped transformation on the target signal to obtain a first intermediate signal, wherein third-order distance walk does not exist in the first intermediate signal.

Optionally, the correcting for third order doppler walk of the target signal resulting from jerk of the target object by constructing a first compensation function, comprising:

determining a search interval and a search step length, wherein the search interval is used for indicating the range of the jerk of the target object detected by the radar, and the search step length is used for indicating the variation of the jerk of the target object detected by the radar each time;

constructing the first compensation function based on the search interval and the search step;

and multiplying the first compensation function and the first intermediate signal to obtain a second intermediate signal.

Optionally, the correcting second-order range walking and second-order doppler walking of the target signal generated by the acceleration of the target object, and correcting first-order range walking of the target signal generated by the velocity of the target object to obtain the corrected signal includes:

performing phase transformation processing on the second intermediate signal to obtain a third intermediate signal, wherein second-order distance walking and second-order Doppler walking do not exist in the third intermediate signal;

and carrying out third-order keystone-shaped transformation on the third intermediate signal to obtain the corrected signal.

Optionally, the performing coherent accumulation on the corrected target signal along a distance frequency dimension and a slow time dimension respectively to obtain a first coherent accumulation result includes:

and performing inverse fast Fourier transform on the corrected target signal along the distance frequency dimension and performing fast Fourier transform along the slow time dimension to obtain the first coherent accumulation result.

Optionally, the first parameter further comprises a velocity ambiguity number of the target object;

after the estimating the first parameter of the target object, the method further comprises:

constructing a second compensation function according to the first parameter;

correcting the distance walking and Doppler walking of the echo signals through the second compensation function;

correcting the range walk of the echo signal generated by the fuzzy speed of the target object to obtain a corrected echo signal;

performing coherent accumulation processing on the corrected echo signals along a distance frequency dimension and a slow time dimension respectively to obtain a second coherent accumulation result;

estimating second parameters of the target object according to the second coherent accumulation result, wherein the second parameters comprise the radial speed of the target object and the radial distance between the target object and the radar.

Optionally, the performing a correction process on the range walk and the doppler walk of the echo signal by the second compensation function includes:

multiplying the second compensation function with the echo signal;

the correcting range walk of the echo signal generated by the blurring speed of the target object to obtain a corrected echo signal, includes:

performing first-order keystone transformation on the corrected echo signal to obtain the corrected echo signal;

the phase-coherent accumulation processing is performed on the corrected echo signal along a distance frequency dimension and a slow time dimension respectively to obtain a second phase-coherent accumulation result, and the phase-coherent accumulation processing includes:

and performing inverse fast Fourier transform on the corrected echo signals along the distance frequency dimension and performing fast Fourier transform along the slow time dimension to obtain the second coherent accumulation result.

In a second aspect of the embodiments of the present application, there is provided an apparatus for estimating parameters of a target object, the apparatus including:

the receiving module is used for receiving an echo signal returned by a target object and converting the echo signal into a distance frequency-slow time domain along a fast time dimension to obtain a target signal;

a correction module, configured to perform correction processing on the range walk and the doppler walk of the echo signal through the second compensation function, where the multiple orders of range walk include a first order range walk, a second order range walk, and a third order range walk, and the multiple orders of doppler walk include a second order doppler walk and a third order doppler walk, and the third order range walk and the third order doppler walk are generated by a jerk of the target object;

the coherent accumulation processing module is used for respectively carrying out coherent accumulation processing on the corrected signal along the distance frequency and the slow time dimension of the distance frequency-slow time domain to obtain a first coherent accumulation result;

and the estimation module is used for estimating a first parameter of the target object according to the first coherent accumulation result, wherein the first parameter comprises the acceleration and the jerk of the target object.

In a third aspect of embodiments of the present application, an electronic device is provided, where the electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and when executed by the processor, the computer program implements the parameter estimation method for a target object according to the first aspect.

In a fourth aspect of the embodiments of the present application, a computer-readable storage medium is provided, where a computer program is stored, and when the computer program is executed by a processor, the computer program implements the parameter estimation method for a target object according to the first aspect.

The beneficial effects of the embodiment of the application include:

the method for estimating parameters of a target object, provided by the embodiment of the present application, includes receiving an echo signal returned by the target object, converting the echo signal into a range frequency-slow time domain along a fast time dimension to obtain a target signal, performing correction processing on a multi-step range walk and a multi-step doppler walk of the target signal to obtain a corrected signal, performing coherent accumulation processing on the corrected signal along the range frequency and the slow time dimension of the range frequency-slow time domain respectively to obtain a first coherent accumulation result, and estimating a first parameter of the target object according to the first coherent accumulation result.

The multi-order range walk and the multi-order Doppler walk in the target signal are corrected to obtain corrected signals, so that after correction, the multi-order range walk and the multi-order Doppler walk in the target signal are eliminated, and the high-speed target object parameter estimation is inaccurate due to the range walk and the Doppler walk, so that the accuracy of the parameter estimation of the target object can be improved by performing subsequent processing according to the corrected signals.

By performing coherent accumulation processing on each corrected signal along the distance frequency and the slow time dimension of the distance frequency-slow time domain, each corrected signal can be accumulated or accumulated, and the signal-to-noise ratio and the signal-to-clutter ratio of each corrected signal can be greatly improved.

Moreover, because the first-order distance walking, the second-order doppler walking, the third-order distance walking and the third-order doppler walking do not exist in each corrected signal, the first coherent accumulation result obtained by coherent accumulation of each corrected signal cannot be influenced by the first-order distance walking, the second-order doppler walking, the third-order distance walking and the third-order doppler walking.

Then, the first parameter of the target object can be accurately estimated by transforming or calculating according to the first coherent accumulation result obtained by performing coherent accumulation processing on the corrected signal, and the problem that the parameter estimation of the radar on the high-speed target object is inaccurate due to distance walking and Doppler walking can be solved.

Thus, the effect of improving the accuracy of parameter estimation on the target object can be achieved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

Fig. 1 is a flowchart of a first method for estimating parameters of a target object according to an embodiment of the present disclosure;

fig. 2 is a flowchart of a second method for estimating parameters of a target object according to an embodiment of the present disclosure;

fig. 3 is a flowchart of a third method for estimating parameters of a target object according to an embodiment of the present application;

fig. 4 is a flowchart of a fourth method for estimating parameters of a target object according to an embodiment of the present application;

fig. 5 is a flowchart of a fifth method for estimating parameters of a target object according to an embodiment of the present application;

fig. 6 is a flowchart of a sixth method for estimating parameters of a target object according to an embodiment of the present application;

fig. 7 is a flowchart of a seventh method for estimating parameters of a target object according to an embodiment of the present application;

fig. 8 is a flowchart of an eighth method for estimating parameters of a target object according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a parameter estimation apparatus for a target object according to an embodiment of the present disclosure;

fig. 10 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Generally, when parameter estimation is performed by a radar, a long-time coherent accumulation mode is adopted, and motion information and doppler information of a target are acquired by using detection information of a range cell of the radar, so as to estimate parameter information of the target. However, with the increasing speed of modern aircraft, and the variable speed movement of these aircraft in general, it is likely that the aircraft will span multiple distance units in a short period of time. However, in the case of detecting and tracking an object by using a long-time coherent accumulation method, if the object spans a plurality of range bins in a short time, the distance is moved, and thus, this scheme has a problem that the parameter estimation of a high-speed object is inaccurate. Wherein, the distance unit refers to the sampling interval of the radar in distance.

Therefore, the embodiment of the present application provides a method for estimating parameters of a target object, which includes receiving an echo signal returned by the target object, converting the echo signal into a range frequency-slow time domain along a fast time dimension to obtain a target signal, performing correction processing on a multi-step range walk and a multi-step doppler walk of the target signal to obtain a corrected signal, performing coherent accumulation processing on the corrected signal along the range frequency and the slow time dimension of the range frequency-slow time domain respectively to obtain a first coherent accumulation result, and estimating a first parameter of the target object according to the first coherent accumulation result, so as to achieve an effect of improving accuracy of parameter estimation of the target object.

It is noted that range walking and doppler walking occur due to relative motion between the radar and the target object. When any target object is within the irradiation range of the radar beam, the distance between the target object and the radar changes continuously due to the movement of the target object, and then the echoes received by the radar from the target object are distributed in several adjacent range cells, so that the parameters of the target object are shifted or expanded in the range dimension and the doppler frequency dimension, which results in the occurrence of range walking and doppler walking.

The embodiment of the present application takes a parameter estimation method of a target object applied in a radar as an example for explanation. It is not shown that the embodiments of the present application can only be applied to radar for parameter estimation of target objects.

In addition, a control processing module with certain processing function can be installed in the radar, or the radar can be in communication connection with a computer device, and the computer device can control the radar to perform parameter estimation or realize other functions. The embodiment of the present application does not limit this.

The following explains the parameter estimation method of the target object provided in the embodiment of the present application in detail.

Fig. 1 is a flowchart of a method for estimating parameters of a target object according to the present application, where the method may be applied to the radar, a control processing module in the radar, or a computer device communicatively connected to the radar. Referring to fig. 1, an embodiment of the present application provides a method for estimating parameters of a target object, including:

step 1001: and receiving an echo signal returned by the target object, and converting the echo signal into a range frequency-slow time domain along a fast time dimension to obtain a target signal.

Alternatively, the target object may be an object within the detection range of the radar.

The echo signal may refer to a signal generated by reflection of a pulse signal transmitted to any object within a detection range of the radar after the radar transmits the pulse signal. The number of echo signals may be many, and the directions of the echo signals may be different, and the echo signals may further include certain data or information that may be used to indicate the distance of the target object monopulse radar, the direction relative to the monopulse radar, the moving speed, the acceleration, the jerk, the size, and/or the like. The embodiment of the present application does not limit this.

In addition, the radar may receive the echo signal through various channels, such as a sum-difference channel, a polarization channel, or any other possible channel. The embodiment of the present application does not limit this.

Wherein the fast time dimension refers to a dimension in which the echo signal is sampled within the echo signal duration. Sampling in the fast time dimension may refer to sampling an echo signal at a certain sampling interval and a certain sampling frequency.

While a slow time dimension exists corresponding to the fast time dimension, the slow time dimension being one dimension in which samples are taken during the repetition period of the echo signals, i.e., the interval between each echo signal. The time interval between each echo signal is the Pulse Repetition Interval (PRI), the inverse of the PRI is the Pulse Repetition Frequency (PRF), and the slow-time sampling frequency is the PRF.

It should be noted that, in the case where the radar transmits periodic pulse signals and receives echo signals of each pulse signal, the echo signals are sampled in the fast time dimension and the slow time dimension, and then the echo signals may be stored in rows, for example, a received echo of a first pulse is placed in a first row, a received echo of a second same pulse is placed in a second row, and so on. The dimension in which the echo signals are stored in rows is thus the fast time dimension, and in addition, the dimension in which the echo signals are stored in columns is the slow time dimension, since the data sampling interval between rows is often greater than the duration of the echo signals. In addition, the fast time dimension and the slow time dimension may constitute a fast time-slow time domain.

The operation of converting the echo signal into the range frequency-slow time domain along the fast time dimension may be converting the echo signal into the range frequency-slow time domain for the fast time dimension in the fast time-slow time domain. The embodiment of the present application does not limit this.

Alternatively, the target signal refers to a signal obtained by converting each received echo signal into a range frequency-slow time domain.

It is worth mentioning that the operation of converting the echo signal into the range frequency-slow time domain along the fast time dimension may be to perform a fourier transform on the echo signal along the fast time dimension to convert the echo signal into the range frequency-slow time domain.

Step 1002: and correcting the multi-step distance walking and the multi-step Doppler walking of the target signal to obtain a corrected signal.

Optionally, the multiple steps of distance walking include first, second and/or third step distance walking.

The multi-step doppler walk includes a second order doppler walk and/or a third order doppler walk.

Alternatively, in the target signal, the velocity of the target object may generate a first order range walk, the acceleration of the target object may generate a second order range walk and a second order doppler walk, and the jerk of the target object may generate a third order range walk and a third order doppler walk.

Optionally, after the correction, there is no first-order range walk, second-order doppler walk, third-order range walk, and third-order doppler walk in the corrected signal.

It should be noted that, after the radar receives each echo signal, the control processing module in the radar or the computer device in communication connection with the radar may perform operations such as analysis and conversion on each echo signal to obtain each data in each echo signal, determine, according to the data, first-order range walking generated by the velocity of the target object, second-order range walking and second-order doppler walking generated by the acceleration of the target object, and third-order range walking and third-order doppler walking generated by the jerk of the target object, and correspondingly adjust parameters such as the phase, frequency, and amplitude of each echo signal to eliminate these multi-order range walking and multi-order doppler walking, thereby obtaining a corrected signal without range walking and doppler walking.

After correction, multi-order distance walking and multi-order Doppler walking in the target signal are eliminated, and because the distance walking and Doppler walking cause that the parameter estimation of the radar to the high-speed target object is not accurate, the subsequent processing is carried out according to the corrected signal, so that the accuracy of the parameter estimation of the target object can be improved.

Step 1003: and performing coherent accumulation processing on the corrected signal along the distance frequency and the slow time dimension of the distance frequency-slow time domain respectively to obtain a first coherent accumulation result.

Optionally, the first coherent accumulation result may be used to characterize an accumulation result obtained by performing coherent accumulation on each corrected signal corresponding to each echo signal received by the radar along a distance frequency dimension and along a slow time dimension.

The first coherent accumulation result may be used to characterize a plurality of target data in each echo signal received by the radar, and may also be used to represent a plurality of target data received by the radar in each range unit.

Each target data may also be used to indicate the velocity, acceleration, jerk of the target object, which range bin of the radar the target object is located within. The embodiment of the present application does not limit this.

The first coherent integration result may be further used to indicate an amplitude of each corrected signal after coherent integration of each corrected signal, and a frequency of each corrected signal corresponding to the slow time dimension.

It is noted that the coherent integration process can determine that a certain phase relationship exists between the corrected signals. Since the phases of the corrected signals can be compared with each other, the phase of each of the other corrected signals can be determined by determining one of the phases. The coherent processing of the corrected signals can improve the signal-to-noise ratio and the signal-to-noise ratio during the accumulation of the corrected signals.

In addition, the signal related to the target object of the echo signal received by the radar may be weak, and a certain amount of noise may also be accompanied in the echo signal, and when the radar performs parameter estimation on the target object, the signal related to the target object needs to be separated from the noise to improve the signal-to-noise ratio and the signal-to-noise ratio.

By performing coherent accumulation processing on each corrected signal along the distance frequency and the slow time dimension of the distance frequency-slow time domain, each corrected signal can be accumulated or accumulated, the signal related to the target object becomes stronger after accumulation, and the noise intensity becomes smaller because the noise is random, so that the signal-to-noise ratio and the signal-to-clutter ratio of each corrected signal can be greatly improved.

Step 1004: and estimating a first parameter of the target object according to the first coherent accumulation result.

Optionally, the first parameter comprises acceleration and jerk of the target object.

The control processing module of the radar or the computer device connected with the radar in communication can perform corresponding operations such as transformation, calculation and the like according to a spectral peak formed by the target object in a distance frequency-slow time domain, the amplitude of each corrected signal after performing coherent accumulation on each corrected signal indicated by the first coherent accumulation result, and the frequency corresponding to the slow time dimension of each corrected signal, so as to estimate the acceleration, the jerk and other possible parameters of the target object. The embodiment of the present application does not limit this.

In the embodiment of the application, a target signal is obtained by receiving an echo signal returned by a target object and converting the echo signal into a range frequency-slow time domain along a fast time dimension, a multi-step range walk and a multi-step doppler walk of the target signal are corrected to obtain a corrected signal, coherent accumulation processing is performed on the corrected signal along the range frequency and the slow time dimension of the range frequency-slow time domain respectively to obtain a first coherent accumulation result, and a first parameter of the target object is estimated according to the first coherent accumulation result.

The multi-order distance walk and multi-order Doppler walk of the target signal generated by the speed, the acceleration and the jerk of the target object are corrected to obtain corrected signals, so that after correction, the multi-order distance walk and the multi-order Doppler walk in the target signal are eliminated, and the parameter estimation of the high-speed target object is inaccurate due to the distance walk and the Doppler walk, and then subsequent processing is performed according to the corrected signals, so that the accuracy of the parameter estimation of the target object can be improved.

Moreover, since the first-order range walking, the second-order doppler walking, the third-order range walking and the third-order doppler walking do not exist in each corrected signal, the first coherent accumulation result obtained by coherent accumulation of each corrected signal cannot be influenced by the first-order range walking, the second-order doppler walking, the third-order range walking and the third-order doppler walking.

Then, the first parameter of the target object, such as the acceleration and jerk of the target object, can be accurately estimated by transforming or calculating according to the first coherent accumulation result obtained by coherent accumulation processing on the corrected signal, and further the problem that the parameter estimation of the radar on the high-speed target object is inaccurate due to distance walking and doppler walking can be solved.

Thus, the effect of improving the accuracy of parameter estimation of the target object can be achieved.

In one possible approach, after receiving the echo signal returned by the target object in step 1001, the following operations may be further performed:

and each echo signal is converted into a baseband signal by performing down-conversion processing on each echo signal.

The baseband signal refers to an original electrical signal without spectrum shifting or conversion, and the spectrum of the baseband signal starts from around zero frequency. The baseband signal is less power attenuated during transmission, so the capacity of the channel transmitting the baseband signal is not changed.

Alternatively, each pulse signal transmitted by the radar may be a chirp signal, and each parameter of each chirp signal may be represented by the following expression (1).

（1）

Wherein the content of the first and second substances,

，

the fast time is indicated by the indication of the fast time,

is the width of each chirp signal, j is a complex constant,

for the chirp rate of each chirp signal,

for the carrier frequency of each chirp signal,

in the case of a slow time, the time,

in the form of a pulse repetition period,

indicating the number of pulse accumulations.

In addition, assume sharing

A target object is

Radial distance of time from the radar

Can be represented by the following formula (2):

（2）

wherein the content of the first and second substances,

representing target object at initial time

The distance in the radial direction from the radar,

、

and

respectively representing target objects

Radial velocity, acceleration, and jerk.

However, the received echo signals of the radar and/or the converted baseband signals according to the respective echo signals can be expressed by the following formula (3):

the formula (3) is as follows:

wherein the content of the first and second substances,

is a target object

The scattering coefficient of (a) is,

indicating the speed of light.

And performing pulse compression processing on the baseband signal to obtain each compressed echo signal.

Each compressed echo signal obtained after the pulse compression processing can be represented by the following expression (4):

（4）

wherein

In order to compress the amplitude of the echo signal,

to compress the bandwidth of the echo signal.

In this case, the target signal may be obtained by converting the compressed echo signal corresponding to the echo signal into the range frequency-slow time domain along the fast time dimension.

Specifically, the compressed echo signals corresponding to the echo signals may be fourier transformed along the fast time dimension to convert each compressed echo signal into the range frequency-slow time domain, and then the target signal may be represented by the following formula (5):

（5）

wherein

Or

Both represent the signal amplitude after fourier transformation along the fast time dimension,

is a time of harmony

The corresponding frequency of the distance is set to,

also referred to as the sampling frequency or frequencies,

has a value interval of

，

Is the sampling rate at which the radar samples the echo signal.

In addition, the speed blur number of the target object may also be estimated when estimating the first parameter of the target object, that is, the first parameter may also include the speed blur number of the target object.

Naturally, whether to estimate the speed ambiguity number of the target object can be determined according to actual needs. The embodiment of the present application does not limit this.

In one possible implementation manner, referring to fig. 2, the performing a correction process on the multi-step range motion and the multi-step doppler motion of the target signal to obtain a corrected signal includes:

step 1005: correcting for third order range walk of the target signal resulting from jerk of the target object.

The third order range walk is generated due to the coupling between the jerk and the range frequency dimension of the target object, and therefore the third order range walk is corrected, i.e., the coupling between the jerk and the range frequency dimension of the target object is eliminated.

Step 1006: third order doppler walk of the target signal resulting from jerk of the target object is corrected by constructing a first compensation function.

Optionally, the first compensation function may be a function for compensating third-order doppler walking, which is established in advance by a relevant technician, or a function for eliminating third-order doppler walking, which is established in real time by a control processing module of the radar or a computer device in communication connection with the radar according to each echo signal received by the radar or each compressed echo signal corresponding to each echo signal and a detection parameter of the radar.

Step 1007: correcting second-order range walk and second-order Doppler walk of the target signal generated by the acceleration of the target object, and correcting first-order range walk of the target signal generated by the velocity of the target object, to obtain the corrected signal.

The second order range walk is generated due to range warping present in the echo signal of the target object, and therefore, the second order range walk is corrected, that is, the range warping present in the echo signal is eliminated.

The first order range walk is due to the sampling frequency

And eliminating coupling between slow times after walking of the second order distance, so correcting the first order distanceWalk away, i.e. at the elimination of the sampling frequency

And eliminating coupling between slow times after second order range walk.

In this way, the first-order range walk, the second-order doppler walk, the third-order range walk, and the third-order doppler walk can be corrected, respectively, to obtain the corrected signal without range walk and doppler walk.

In one possible implementation, referring to fig. 3, correcting for third order distance walk of the target signal resulting from jerk of the target object includes:

step 1008: and performing three-order Keystone (KT) transformation on the target signal to obtain a first intermediate signal.

Optionally, there is no third order range walk in the first intermediate signal.

Illustratively, the target signal of the target object can be represented by the following equation (6) in the distance frequency domain dimension:

the formula (6) is as follows:

the operation of step 1008 may be to perform a third-order KT transformation on the target signal represented by equation (6) by a control processing module of the radar or a computer device communicatively connected to the radar to eliminate third-order range walk, and specifically may perform transformation according to equation (7) below to obtain the first intermediate signal, which may be represented by equation (8) below.

（7）

The formula (8) is as follows:

it can be seen that the third order distance walk has been corrected.

In one possible implementation, referring to fig. 4, correcting for third order doppler walk of the target signal resulting from jerk of the target object by constructing a first compensation function, includes:

step 1009: and determining a search interval and a search step.

Optionally, the search interval is used to indicate a range of jerks in which the radar detects the target object. The search step is used to indicate the variation of the jerk of the radar detecting the target object each time.

The search interval and the search step size may be set in advance by a person skilled in the art. The embodiment of the present application does not limit this.

Step 1010: the first compensation function is constructed based on the search interval and the search step.

Illustratively, assume that the search interval is

The search step is

Then, the first compensation function constructed based on the search interval and the search step can be represented by the following formula (9):

（9）

step 1011: the first compensation function is multiplied by the first intermediate signal to obtain a second intermediate signal.

Optionally, there is no third order range walk in the second intermediate signal, nor is there a third order doppler walk.

Illustratively, the first compensation function may be represented by equation (9) above, and the first intermediate signal may be represented by equation (8) above.

The operation of step 1011 may be that the first compensation function represented by the above formula (8) is multiplied by the first intermediate signal represented by the above formula (9) by a control processing module of the radar or a computer device communicatively connected to the radar to obtain the second intermediate signal represented by the following formula (10).

（10）

It can be seen that the third order doppler walk has been corrected.

In one possible implementation, referring to fig. 5, correcting second-order range walk and second-order doppler walk of the target signal generated by the acceleration of the target object and correcting first-order range walk of the target signal generated by the velocity of the target object to obtain the corrected signal includes:

step 1012: and performing phase conversion processing on the second intermediate signal to obtain a third intermediate signal.

Optionally, there is no second order range walk and second order doppler walk in the third intermediate signal.

Of course, there is also no third order range walk and third order doppler walk in this third intermediate signal.

Alternatively, the phase transformation process may be referred to as discrete polynomial phase transformation (DPT). The embodiment of the present application does not limit this.

For example, the control processing module of the radar or the computer device communicatively connected to the radar may perform the phase transformation processing according to the following equation (11), specifically, may perform DPT on the second intermediate signal represented by the above equation (10), and the obtained third intermediate signal may be represented by the following equation (12).

（11）

Formula (12) is as follows:

（12）

wherein the content of the first and second substances,

representing a fixed delay constant.

It is noted that DPT may reduce the phase order of the target signal, and thus DPT of the second intermediate signal in the range frequency dimension may reduce the signal order in the echo signal of the target object after the third order range walk and the third order doppler walk have been corrected.

It can be seen that the second order range walk and the second order doppler walk have been corrected.

Step 1013: and performing third-order keystone transformation on the third intermediate signal to obtain the corrected signal.

Illustratively, the operation of step 1013 may be that the third intermediate signal represented by equation (12) is subjected to a third-order KT transformation by a control processing module of the radar or a computer device communicatively connected to the radar to eliminate a first-order range walk, and specifically may be subjected to a transformation according to equation (13) below to obtain the corrected signal, which may be represented by equation (14) below.

（13）

（14）

Wherein, the first and the second end of the pipe are connected with each other,

is the slow time after the third-order KT transformation,

to compress the bandwidth of the echo signal.

In addition, for a narrow-band signal,

therefore, it is also possible to formulate by Taylor expansion

，

The corrected signal represented by the following expression (15) is obtained by substituting the signal into the above expression (14).

（15）

As can be seen from the above formula (15),

and therefore can be ignored, so the first order range walk has been corrected.

In one possible implementation, referring to fig. 6, performing coherent integration on the corrected target signal along the range frequency dimension and the slow time dimension, respectively, to obtain a first coherent integration result, including:

step 1014: and performing Inverse Fast Fourier Transform (IFFT) on the corrected target signal along the distance frequency dimension and performing Fast Fourier Transform (FFT) along the slow time dimension to obtain the first coherent accumulation result.

Illustratively, the obtained first coherent integration result may be represented by the following formula (16):

（16）

wherein

Representing the amplitude of the echo after coherent accumulation,

is the frequency corresponding to the slow time,

and

corresponding to FFT and IFFT operations, respectively.

In one possible approach, after obtaining the first coherent integration result as shown in the above equation (16), the first parameter of the target object may be estimated according to the first coherent integration result as shown in the above equation (16).

Illustratively, in the event that the jerk of the target object is matched, the target object will be

And

a spectral peak is formed. Thus of the target object

And

the estimated values are:

and

。

thus, the acceleration and jerk of the target object can be accurately estimated.

One possible way, the radial velocity of the target object i, taking into account the blur velocity of the target object

Can be represented by the following formula (17):

（17）

represents the fuzzy speed of the target object i, satisfies

。

The speed is blind.

Is the wavelength.

Indicating the pulse repetition frequency.

Is a target object

The velocity blur number of (2).

Is determined by the PRF.

That is, the radial velocity of the target object i, generally,

can also be used

And (4) expressing.

When the blur speed of the target object is considered, the following expression (18) can be obtained, and the following expression (18) can be simplified, and the following expression (19) can also be obtained.

（18）

Due to the above formula (18)

Then, the following formula (19) can be obtained:

（19）

in addition, when the fuzzy speed of the target object is considered, the speed fuzzy number of the target object i can be estimated according to the first coherent integration result when the step 1004 is executed

。

In particular, can be according to the above formula

And the above formula

Estimated

The estimated value of (d) may be:

。

thus, the subsequent speed fuzzy number according to the target object is convenient

A radial velocity and/or a radial distance of the target object is estimated.

In a possible implementation, referring to fig. 7, after estimating the first parameter of the target object, the method further includes:

step 1015: a second compensation function is constructed based on the first parameter.

The second compensation function may be a function of a first-order range walking, a second-order doppler walking, a third-order range walking, and a third-order doppler walking, which are constructed in real time by a control processing module of the radar or a computer device in communication with the radar according to the first parameter of the target object estimated by the radar, to eliminate the echo signal.

The second compensation function may also be used to cancel range walk in the echo signal caused by the target object's blur velocity.

Illustratively, the second compensation function may be represented by the following equation (20):

（20）

step 1016: and correcting the distance movement and the Doppler movement of the echo signals by the second compensation function.

Optionally, the range walk of the echo signal comprises a first order range walk, a second order range walk, and/or a third order range walk.

The doppler walk of the echo signal includes a second order doppler walk and/or a third order doppler walk.

Step 1017: and correcting the distance walk of the echo signal generated by the fuzzy speed of the target object to obtain a corrected echo signal.

Optionally, the first order range walk, the second order doppler walk, the third order range walk, the third order doppler walk, and the range walk of the echo signal resulting from the blur velocity of the target object are absent from the corrected echo signal.

Step 1018: and respectively carrying out coherent accumulation processing on the corrected echo signals along the distance frequency dimension and the slow time dimension to obtain a second coherent accumulation result.

Optionally, the second coherent accumulation result may be used to characterize an accumulation result obtained by coherently accumulating along a distance frequency dimension and along a slow time dimension each corrected echo signal corresponding to each echo signal received by the radar.

The second coherent accumulation result is also used to indicate the velocity, acceleration, jerk of the target object, which range bin of the radar the target object is located within.

The second coherent accumulation result may also be used to indicate the amplitude of each corrected echo signal after coherent accumulation of each corrected echo signal, the frequency of each corrected echo signal corresponding to the slow time dimension, and the distance of the target object corresponding to each corrected echo signal from the radar. The embodiment of the present application does not limit this.

Step 1019: and estimating a second parameter of the target object according to the second coherent accumulation result.

Optionally, the second parameter comprises a radial velocity of the target object, a radial distance of the target object from the radar.

The control processing module of the radar or the computer equipment in communication connection with the radar can accurately estimate second parameters of the target object, such as the radial speed and the radial distance of the target object, according to the transformation or calculation of the second coherent accumulation result, so that the problem that the parameter estimation of the radar on a high-speed target object is inaccurate due to distance walking and Doppler walking can be solved, and the problem that the radial speed and the radial distance estimation of the radar on the high-speed target object are inaccurate due to distance walking generated by the fuzzy speed of the target object can be solved.

Therefore, on the basis of accurately estimating the acceleration and the jerk of the target object, the radial speed and the radial distance of the target object can be accurately estimated, and the effect of improving the accuracy of parameter estimation of the target object can be further achieved.

In a possible implementation manner, referring to fig. 8, the correction processing of the range and doppler shifts of the echo signal by the second compensation function includes:

step 1020: the second compensation function is multiplied with the echo signal.

Illustratively, the second compensation function may be a function as shown in equation (20) above, and multiplying the second compensation function by the echo signal may obtain a signal as shown in equation (21) below:

（21）

correcting the range walk of the echo signal generated by the blurring speed of the target object to obtain a corrected echo signal, comprising:

step 1021: and performing first-order keystone transformation on the corrected echo signal to obtain the corrected echo signal.

Illustratively, a first order KT transform may be performed on a signal obtained by multiplying the second compensation function with the echo signal, such as the signal represented by equation (21) above.

Can pass through

The signal represented by the above equation (21) is subjected to a first-order KT transform.

Wherein

Slow time after first order KT transform.

The coherent accumulation processing is performed on the corrected echo signal along the distance frequency dimension and the slow time dimension respectively to obtain a second coherent accumulation result, which includes:

step 1022: and performing inverse fast Fourier transform on the corrected echo signal along the distance frequency dimension and performing fast Fourier transform along the slow time dimension to obtain the second coherent accumulation result.

Illustratively, the echo signal after correction, which is represented by the following equation (22), can be obtained by performing IFFT along the distance frequency dimension and FFT along the slow time dimension on the signal represented by the above equation (21) subjected to the first-order KT transformation:

（22）

wherein

Representing the echo amplitude. In addition, it can be seen from the above equation (22) that the target object is to be

And

form a focused spectral peak, and therefore, the base band velocity

Is estimated as

Thus can obtain

The estimated value shown in the following equation (23)

。

（23）

Therefore, the radial velocity of the target object can be accurately estimated, and the effect of improving the accuracy of parameter estimation of the target object can be achieved.

The following describes a device, an apparatus, and a computer-readable storage medium for executing the method for estimating parameters of a target object provided in the present application, and specific implementation procedures and technical effects thereof are referred to above, and will not be described again below.

Fig. 9 is a schematic structural diagram of a parameter estimation apparatus for a target object according to an embodiment of the present application, and referring to fig. 9, the apparatus includes:

the receiving module 201 is configured to receive an echo signal returned by a target object, and convert the echo signal into a range frequency-slow time domain along a fast time dimension to obtain a target signal.

The correcting module 202 is configured to perform correction processing on the multi-order distance movement and the multi-order doppler movement of the target signal to obtain a corrected signal.

The multi-step distance walking includes first-order distance walking, second-order distance walking, and third-order distance walking. The multi-step doppler walk includes a second order doppler walk and a third order doppler walk.

The third order range walk and the third order doppler walk are the result of jerk of the target object.

And the coherent accumulation processing module 203 is configured to perform coherent accumulation processing on the corrected signal along the distance frequency and the slow time dimension of the distance frequency-slow time domain, respectively, to obtain a first coherent accumulation result.

The estimating module 204 is configured to estimate a first parameter of the target object according to the first coherent accumulation result.

Optionally, the correction module 202 is further configured to correct for third order distance walk of the target signal resulting from jerk of the target object. Third order doppler walk of the target signal resulting from jerk of the target object is corrected by constructing a first compensation function. Correcting second-order range walk and second-order Doppler walk of the target signal generated by the acceleration of the target object, and correcting first-order range walk of the target signal generated by the velocity of the target object, to obtain the corrected signal.

Optionally, the correction module 202 is further configured to perform third-order keystone transform on the target signal to obtain a first intermediate signal, where no third-order distance walk exists in the first intermediate signal.

Optionally, the correction module 202 is further configured to determine a search interval and a search step, where the search interval is used to indicate a range of jerks of the radar detecting the target object, and the search step is used to indicate a variation of the jerk of the radar detecting the target object each time. The first compensation function is constructed based on the search interval and the search step. The first compensation function is multiplied by the first intermediate signal to obtain a second intermediate signal.

Optionally, the correcting module 202 is further configured to perform phase transformation processing on the second intermediate signal to obtain a third intermediate signal, where the second-order range walking and the second-order doppler walking do not exist in the third intermediate signal. And carrying out third-order keystone transformation on the third intermediate signal to obtain the corrected signal.

Optionally, the coherent accumulation processing module 203 is further configured to perform an inverse fast fourier transform on the corrected target signal along the distance frequency dimension and perform a fast fourier transform along the slow time dimension to obtain the first coherent accumulation result.

Optionally, the apparatus further comprises a speed blur correction module.

The speed blur correction module is used for constructing a second compensation function according to the first parameter. The range and doppler excursions of the echo signal resulting from the velocity, acceleration and jerk of the target object are corrected by the second compensation function. And correcting the distance walk of the echo signal generated by the fuzzy speed of the target object to obtain a corrected echo signal. And respectively carrying out coherent accumulation processing on the corrected echo signals along the distance frequency dimension and the slow time dimension to obtain a second coherent accumulation result. And estimating a second parameter of the target object according to the second coherent accumulation result.

The second parameters include a radial velocity of the target object, a radial distance of the target object from the radar.

The velocity blur correction module is further configured to multiply the second compensation function with the echo signal.

The speed fuzzy correction module is also used for carrying out first-order wedge-shaped transformation on the corrected echo signal to obtain the corrected echo signal.

The velocity blur correction module is further configured to perform inverse fast fourier transform on the corrected echo signal along the distance frequency dimension and perform fast fourier transform along the slow time dimension to obtain the second coherent accumulation result.

The above-mentioned apparatus is used for executing the method provided by the foregoing embodiment, and the implementation principle and technical effect are similar, which are not described herein again.

These above modules may be one or more integrated circuits configured to implement the above methods, such as: one or more Application Specific Integrated Circuits (ASICs), or one or more microprocessors, or one or more Field Programmable Gate Arrays (FPGAs), etc. For another example, when one of the above modules is implemented in the form of a Processing element scheduler code, the Processing element may be a general-purpose processor, such as a Central Processing Unit (CPU) or other processor capable of calling program code. As another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

Fig. 10 is a schematic structural diagram of an electronic device according to an embodiment of the present application. Referring to fig. 10, the electronic device includes: a memory 301 and a processor 302, wherein the memory 301 stores a computer program operable on the processor 302, and the processor 302 executes the computer program to implement the steps of any of the above-mentioned method embodiments.

The electronic device may be the radar described above, or may be a computer device communicatively coupled to the radar. The embodiment of the present application does not limit this.

The embodiments of the present application also provide a computer-readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the steps in the above-mentioned method embodiments can be implemented.

Optionally, the present application also provides a program product, such as a computer-readable storage medium, comprising a program which, when executed by a processor, is adapted to perform any of the above embodiments of the method for parameter estimation of a target object.

In the embodiments provided in the present invention, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, a division of a unit is only a logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

The integrated unit implemented in the form of a software functional unit may be stored in a computer-readable storage medium. The software functional unit is stored in a storage medium and includes several instructions to enable a computer device (which may be a personal computer, a server, or a network device) or a processor (processor) to execute some steps of the methods according to the embodiments of the present invention. And the aforementioned storage medium includes: a U disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made to the present application by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method of parameter estimation of a target object, the method comprising:

estimating a first parameter of the target object according to the first coherent accumulation result, wherein the first parameter comprises the acceleration, the jerk and the speed ambiguity of the target object;

constructing a second compensation function according to the first parameter;

and estimating second parameters of the target object according to the second coherent accumulation result, wherein the second parameters comprise the radial speed of the target object and the radial distance between the target object and a radar.

2. The method of claim 1, wherein the step of correcting the target signal for multi-step range and multi-step doppler shifts to obtain a corrected signal comprises:

correcting third order Doppler walk of the target signal resulting from jerk of the target object by constructing a first compensation function;

3. The method of parameter estimation of a target object of claim 2, wherein the correcting for third order range walk of the target signal resulting from jerk of the target object comprises:

4. The method of parameter estimation of a target object of claim 3, wherein said correcting for third order Doppler shifts in the target signal resulting from jerk of the target object by constructing a first compensation function comprises:

constructing the first compensation function based on the search interval and the search step length;

5. The method of estimating parameters of a target object according to claim 4, wherein said correcting for second-order range walk and second-order Doppler walk of said target signal resulting from acceleration of said target object and correcting for first-order range walk of said target signal resulting from velocity of said target object to obtain said corrected signal comprises:

and performing third-order keystone transformation on the third intermediate signal to obtain the corrected signal.

6. The method for estimating parameters of a target object according to claim 1, wherein the performing coherent accumulation on the corrected target signal along a distance frequency dimension and a slow time dimension, respectively, to obtain a first coherent accumulation result comprises:

7. The method for parameter estimation of a target object according to any of claims 1 to 6, wherein said correction processing of range and Doppler walk of the echo signal by the second compensation function comprises:

multiplying the second compensation function with the echo signal;

the correcting distance walk of the echo signal generated by the fuzzy speed of the target object to obtain a corrected echo signal includes:

8. A parameter estimation apparatus for a target object, applied to radar, the apparatus comprising:

a correction module, configured to perform correction processing on a multi-order distance walking and a multi-order doppler walking of the target signal to obtain a corrected signal, where the multi-order distance walking includes a first-order distance walking, a second-order distance walking, and a third-order distance walking, the multi-order doppler walking includes a second-order doppler walking and a third-order doppler walking, and the third-order distance walking and the third-order doppler walking are generated by a jerk of the target object;

the estimation module is used for estimating first parameters of the target object according to the first coherent accumulation result, wherein the first parameters comprise the acceleration and the jerk of the target object and the speed fuzzy number of the target object;

the estimation module is further used for constructing a second compensation function according to the first parameter; correcting the distance walking and Doppler walking of the echo signals through the second compensation function; correcting the range walk of the echo signal generated by the fuzzy speed of the target object to obtain a corrected echo signal; respectively carrying out coherent accumulation processing on the corrected echo signals along a distance frequency dimension and a slow time dimension to obtain a second coherent accumulation result; and estimating second parameters of the target object according to the second coherent accumulation result, wherein the second parameters comprise the radial speed of the target object and the radial distance between the target object and a radar.

9. An electronic device, comprising: a memory in which a computer program operable on the processor is stored, and a processor that, when executing the computer program, implements the steps of the method for parameter estimation of a target object of any of claims 1 to 7.

10. A computer-readable storage medium, characterized in that a computer program is stored thereon, which, when being executed by a processor, carries out the steps of the method for parameter estimation of a target object of any one of claims 1 to 7.