阅读说明：本技术 一种相关干涉仪测向方法、系统、设备及存储介质 (Correlation interferometer direction finding method, system, equipment and storage medium ) 是由 张海拓 于 2021-09-28 设计创作，主要内容包括：本发明公开了一种相关干涉仪测向方法、系统、设备及存储介质,其测向方法包括按照预设频率采集测向天线中各测量振子所接收到的信号,并获取各测量振子所对应的幅度和相位信息；利用信号幅度对相位信息进行加权处理,与相位样本库预存的各角度相位矢量进行相关运算,以获得各角度对应的相关系数；根据各角度所对应的相关系数对信号来波方向进行计算以输出最终的测向结果。本发明在相关运算过程中对各天线振子的信号幅度进行归一化,利用该归一化幅度矢量对相位相关运算进行加权,降低弱信号对相关结果的影响,提升弱信号条件下的测向精度。(The invention discloses a direction finding method, a system, equipment and a storage medium of a correlation interferometer, wherein the direction finding method comprises the steps of collecting signals received by each measuring oscillator in a direction finding antenna according to preset frequency, and acquiring amplitude and phase information corresponding to each measuring oscillator; weighting the phase information by using the signal amplitude, and performing correlation operation on the phase information and phase vectors of all angles prestored in a phase sample library to obtain correlation coefficients corresponding to all angles; and calculating the incoming wave direction of the signal according to the correlation coefficient corresponding to each angle so as to output a final direction finding result. According to the invention, the signal amplitude of each antenna element is normalized in the correlation operation process, and the normalized amplitude vector is used for weighting the phase correlation operation, so that the influence of weak signals on the correlation result is reduced, and the direction finding precision under the weak signal condition is improved.)

1. A method of correlation interferometer direction finding, comprising:

acquiring signals received by each measuring oscillator in the direction-finding antenna according to a preset frequency, and acquiring amplitude and phase information corresponding to each measuring oscillator;

weighting the phase information by using the signal amplitude to obtain a correlation coefficient corresponding to each angle;

acquiring a vector angle and a correlation coefficient value corresponding to a peak point of a correlation coefficient vector;

acquiring a sampling interval of a sample library, marking two points adjacent to a peak point according to the sampling interval, and acquiring vector angles of two marked points adjacent to the peak point and corresponding correlation coefficient values;

and calculating to obtain a final direction-finding angle by a binomial curve fitting method according to the vector angle and the correlation coefficient value of the peak point and two adjacent points of the peak point.

2. The correlation interferometer direction-finding method of claim 1, wherein obtaining phase information of each measurement oscillator comprises collecting phase difference vectors between all the measurement oscillators and a reference oscillator, and phase difference vectors of sample data corresponding to a preset frequency read from a sample library.

3. The correlation interferometer direction finding method of claim 2, wherein the sample library is established by:

and controlling the direction-finding antenna to sequentially transmit signals according to preset frequency, direction and angle intervals in the range around the antenna, recording phase difference vectors between each measuring oscillator and the reference oscillator at each angle, and storing all phase difference data serving as sample data in a sample library.

4. The correlation interferometer direction finding method of claim 2, wherein prior to weighting the phase information with the signal amplitude, further comprising:

carrying out vector search on the signal amplitude of each measuring oscillator to obtain a maximum amplitude value;

and respectively carrying out normalization processing on the amplitude vector of each measuring vibrator by combining the maximum amplitude value to obtain a normalized amplitude vector value corresponding to each measuring vibrator.

5. The correlation interferometer direction finding method of claim 4, wherein the correlation coefficient is calculated by the formula:

；

wherein n is the number of antenna elements;the normalized amplitude vector of the jth measuring oscillator is obtained;a phase difference vector of a jth measuring oscillator in the sample library at an ith angle interval is obtained;is the phase difference vector between the jth measurement transducer and the reference transducer.

6. The correlation interferometer direction-finding method of claim 1, wherein the binomial curve fitting method corresponds to the formula:

；

wherein the content of the first and second substances,the final direction finding result is obtained;the vector angle corresponding to the peak point;the correlation coefficient value corresponding to the peak value point;andtwo points adjacent to the peak point respectively,is composed ofThe value of the correlation coefficient of the point,is composed ofThe value of the correlation coefficient of the point.

7. A correlation interferometer direction finding system, characterized in that the correlation interferometer direction finding method according to any one of claims 1-6 is performed, comprising:

the signal acquisition module is used for acquiring signals received by each measuring oscillator in the direction-finding antenna according to preset frequency;

the amplitude phase calculation module is used for calculating the amplitude of the received signal of each measuring oscillator and the phase difference between each measuring oscillator and the reference oscillator;

the correlation coefficient calculation module is used for reading sample data corresponding to the preset frequency from the sample library, performing weighting processing on the phase difference vector by using the signal amplitude, and performing correlation calculation by combining the sample data to obtain correlation coefficients corresponding to all angles;

and the angle calculation module is used for calculating the incoming wave direction of the signal according to the correlation coefficient corresponding to each angle so as to output a final direction finding result.

8. A correlation interferometer apparatus comprising a processor, a memory and a computer program stored on the memory and executable on the processor, the processor implementing the correlation interferometer direction finding method of any of claims 1 to 6 when executing the computer program.

9. A computer-readable storage medium, having stored thereon a computer program which, when executed, implements the correlation interferometer direction finding method of any of claims 1-6.

Technical Field

The present invention relates to the field of radio direction finding, and in particular, to a method, a system, a device, and a storage medium for direction finding of a correlation interferometer.

Background

With the development of communication technology, radio interference phenomena are more and more serious, and in order to efficiently utilize limited spectrum resources and ensure the smoothness of normal communication, radio monitoring and direction finding must be performed. Radio direction finding is a process of determining the incoming wave direction of radio waves by using an instrument device according to the propagation characteristics of the electromagnetic waves.

The correlation interferometer is a direction-finding system developed on the basis of the direction finding of the interferometer, which substantially utilizes the one-to-one correspondence relationship between the direction of a radio signal relative to the reference direction of an antenna array and the phase distribution of signals among antenna array elements, and if the phase distribution among the antenna array elements is known, the incident direction of the radio signal can be obtained by comparing the similarity of the phase distribution with the phase distribution of incoming waves of each direction and each frequency stored in advance. The correlation interferometer adopts the correlation processing technology, weakens the adverse effect of mutual coupling, carriers and the like on the direction-finding precision in the traditional interferometer, and is a high-precision direction-finding technology which is widely applied.

In the traditional direction-finding technology of the correlation interferometer, omnidirectional antenna oscillators are adopted, phase information received by each antenna oscillator is mainly utilized to form an antenna array, and after the antenna array is formed, due to the influences of mutual coupling, oscillator shielding and the like, a directional diagram of the antenna oscillator is distorted and deviates from an ideal omnidirectional characteristic, when the signal receiving power is low, partial oscillators receive weaker signals, the phase measurement errors of the partial oscillators become larger, and the overall direction-finding accuracy is reduced.

Disclosure of Invention

In order to overcome the defects of the prior art, an object of the present invention is to provide a direction finding method for a correlation interferometer, which can improve the direction finding accuracy under the condition of weak signals.

The invention also aims to provide a correlation interferometer direction-finding system.

It is a further object of the present invention to provide a correlation interferometer apparatus.

It is a further object of the present invention to provide a computer readable storage medium.

One of the purposes of the invention is realized by adopting the following technical scheme:

a correlation interferometer direction finding method, comprising:

acquiring signals received by each measuring oscillator in the direction-finding antenna according to a preset frequency, and acquiring amplitude and phase information corresponding to each measuring oscillator;

weighting the phase information by using the signal amplitude to obtain a correlation coefficient corresponding to each angle;

acquiring a vector angle and a correlation coefficient value corresponding to a peak point of a correlation coefficient vector;

acquiring a sampling interval of a sample library, marking two points adjacent to a peak point according to the sampling interval, and acquiring vector angles of two marked points adjacent to the peak point and corresponding correlation coefficient values;

and calculating to obtain a final direction-finding angle by a binomial curve fitting method according to the vector angle and the correlation coefficient value of the peak point and two adjacent points of the peak point.

Further, the obtaining of the phase information of each measurement oscillator includes collecting phase difference vectors between all the measurement oscillators and the reference oscillator, and reading the phase difference vector of sample data corresponding to the preset frequency from the sample library.

Further, the establishment method of the sample library comprises the following steps:

and controlling the direction-finding antenna to sequentially transmit signals according to preset frequency, direction and angle intervals in the range around the antenna, recording phase difference vectors between each measuring oscillator and the reference oscillator at each angle, and storing all phase difference data serving as sample data in a sample library.

Further, before weighting the phase information by using the signal amplitude, the method further includes:

carrying out vector search on the signal amplitude of each measuring oscillator to obtain a maximum amplitude value;

and respectively carrying out normalization processing on the amplitude vector of each measuring vibrator by combining the maximum amplitude value to obtain a normalized amplitude vector value corresponding to each measuring vibrator.

Further, the formula for calculating the correlation coefficient is:

；

wherein n is the number of antenna elements;the normalized amplitude vector of the jth measuring oscillator is obtained;a phase difference vector of a jth measuring oscillator in the sample library at an ith angle interval is obtained;is the phase difference vector between the jth measurement transducer and the reference transducer.

Further, the formula corresponding to the binomial curve fitting method is as follows:

；

wherein the content of the first and second substances,the final direction finding result is obtained;the vector angle corresponding to the peak point;the correlation coefficient value corresponding to the peak value point;andtwo points adjacent to the peak point respectively,is composed ofThe value of the correlation coefficient of the point,is composed ofThe value of the correlation coefficient of the point.

The second purpose of the invention is realized by adopting the following technical scheme:

a correlation interferometer direction finding system performing the correlation interferometer direction finding method as described above, comprising:

the signal acquisition module is used for acquiring signals received by each measuring oscillator in the direction-finding antenna according to preset frequency;

the amplitude phase calculation module is used for calculating the amplitude of the received signal of each measuring oscillator and the phase difference vector between each measuring oscillator and the reference oscillator;

the correlation coefficient calculation module is used for reading sample data corresponding to the preset frequency from the sample library, performing weighting processing on the phase difference vector by using the signal amplitude, and performing correlation calculation by combining the sample data to obtain correlation coefficients corresponding to all angles;

and the angle calculation module is used for calculating the incoming wave direction of the signal according to the correlation coefficient corresponding to each angle so as to output a final direction finding result.

The third purpose of the invention is realized by adopting the following technical scheme:

a correlation interferometer apparatus comprising a processor, a memory and a computer program stored on the memory and executable on the processor, the processor implementing the correlation interferometer direction finding method described above when executing the computer program.

The purpose of the invention is realized by adopting the following technical scheme:

a computer-readable storage medium, on which a computer program is stored which, when executed, implements the correlation interferometer direction finding method described above.

Compared with the prior art, the invention has the beneficial effects that:

the invention calculates the phase difference of the signals directly received by each antenna oscillator and the reference oscillator to form a group of phase difference vectors, compares the phase difference vectors with all the phase difference vectors of the corresponding frequencies in a sample library, finds out a group of sample phase difference vectors closest to the measured phase difference vectors, and calculates the direction information of the incident signals; according to the invention, the similarity degree of the phase difference vector and the sample data obtained by current test is reflected through correlation operation, the measurement amplitude of each antenna element is normalized in the correlation operation process, the normalized amplitude vector is used for weighting the phase correlation operation, the influence of weak signals on correlation results is reduced, and the direction finding precision under the condition of weak signals is improved.

Drawings

FIG. 1 is a schematic flow chart of a correlation interferometer direction finding method of the present invention;

FIG. 2 is a schematic diagram of the correlation coefficient and direction finding angle of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.

Example one

The embodiment provides a direction finding method for a correlation interferometer, which improves a direction finding algorithm and is applicable to single-channel, double-channel and multi-channel correlation interferometer systems; when correlation operation is carried out, the direction finding result of the correlation interferometer is weighted by using amplitude information of signals received by the antenna elements, the correlation operation result is ensured to mainly depend on the antenna elements with stronger receiving amplitude, the influence of the antenna elements with weaker receiving signal amplitude on the correlation operation result is reduced, and therefore the direction finding precision under the condition of weak signals is improved.

As shown in fig. 1, the direction finding method of the correlation interferometer of the present embodiment specifically includes the following steps:

step S1: acquiring signals received by each measuring oscillator in the direction-finding antenna according to a preset frequency, and acquiring the signal amplitude of each measuring oscillator and phase difference information relative to a reference oscillator;

step S2: weighting the phase difference information by using the signal amplitude, and carrying out correlation calculation on the phase difference information corresponding to the sample library to obtain correlation coefficients corresponding to all angles;

step S3: and calculating the incoming wave direction of the signal according to the correlation coefficient corresponding to each angle so as to output a final direction finding result.

In this embodiment, before signal acquisition, parameters such as a designated frequency and a designated broadband need to be preset, so that the relevant interferometer can receive signals according to the preset parameters such as the frequency and the broadband; meanwhile, each measuring oscillator in the direction-finding antenna array in the correlation interferometer can receive radio signals.

After each measuring oscillator receives a radio signal according to a preset frequency, the amplitude and the phase of the signal can be obtained. The amplitude vector for recording the amplitude components of all the oscillators isThe phase difference vector composed of the phase differences of all the oscillators and the reference oscillator is。

In this embodiment, after obtaining the amplitude vector of the measurement oscillator, normalization processing needs to be performed on the amplitude; the normalization processing method comprises the following steps:

searching the maximum amplitude vector value of the amplitude of the measurement signal of each measurement oscillator in the amplitude vector E, and recording the maximum amplitude vector value as Emax;

combining the maximum amplitude vector value to respectively carry out normalization processing on the amplitude vector of each measuring oscillator so as to obtain a normalized amplitude vector value corresponding to each measuring oscillator, wherein the calculation formula of the normalized amplitude vector value is as follows:(ii) a Where E is the magnitude vector and Emax is the maximum magnitude vector value.

The magnitude vector obtained by the normalization operation is used for weighting the phase information when the correlation coefficient operation is performed. In this embodiment, the phase information used for calculating the correlation coefficient needs to acquire phase difference vectors between all the measurement oscillators and the reference oscillator, and also needs to read a phase difference vector of sample data corresponding to a preset frequency from the sample library, and after the measured phase difference vector and the phase difference vector of the sample are acquired, the measured phase difference vector is subjected to weighting calculation and then is subjected to correlation calculation with the phase difference vector of the sample, so as to obtain the corresponding correlation coefficient.

The method for establishing the sample library in this embodiment is as follows:

the method comprises the steps of controlling a direction-finding antenna to sequentially transmit signals according to preset frequency, direction and angle intervals in the range around the antenna in a standard field, recording phase difference vectors between each measuring oscillator and a reference oscillator at each angle, and storing all phase difference data serving as sample data in a sample library. The standard field refers to a wide field in a non-reflection environment, and interference of redundant signals in the environment to the sample test can be reduced. In the sample data acquisition process, signals are transmitted at a certain angle interval within 360 degrees around the antenna at each frequency, phase difference vectors corresponding to each angle interval at each frequency are recorded, and all the phase difference vectors recorded in a standard field are integrated into sample data and stored in a sample database.

In this embodiment, after obtaining the phase difference vector obtained by testing according to the preset frequency, the sample data corresponding to the current testing frequency is read from the sample library and recorded as，For the phase difference vector at the ith angular interval in the sample data,(ii) a And then, performing correlation coefficient operation by testing the obtained phase difference vector and the phase difference vector obtained in the sample library, wherein the correlation coefficient at the ith angle interval is calculated as follows:

；

wherein n is the number of antenna elements;normalized amplitude for jth measuring transducerA vector;a phase difference vector of a jth measuring oscillator in the sample library at an ith angle interval is obtained;is the phase difference vector between the jth measurement transducer and the reference transducer.

In this embodiment, after the difference calculation is performed on the phase difference vector obtained by the test and the phase difference vector obtained in the sample library, the normalized amplitude vector is used to weight the phase information after the difference calculation, so that the influence of the weak signal on the correlation result is reduced, and the direction finding precision under the weak signal condition is improved.

In addition, the operation formula of the correlation coefficient in the embodiment may also be replaced by absolute value or sum of squares operation; the correlation coefficient calculation formula using absolute values is as follows:

；

the correlation coefficient calculation formula using the sum of squares is as follows:

；

the correlation coefficient calculation is performed by using the absolute value or the sum of squares, and the angle around 0 ° can be specially processed, for example, the two angles of 0 ° and 359 ° are different by 1 °, and if the difference between the two phase difference vectors is simply calculated, the calculation result is erroneous, so that the calculation needs to be changed by using the absolute value or the sum of squares. The use of cos function for correlation coefficient calculation can avoid the problem.

In this embodiment, after obtaining the correlation coefficient, angle calculation needs to be performed, and the test angle calculation method includes:

1) the sampling interval of the preset sample library is phi, i.e. the corresponding angles of the sample vectors are 0,、；

2) Searching the peak value according to the correlation coefficient vector, and acquiring the vector angle corresponding to the peak value point of the correlation coefficient vectorAnd correlation coefficient value；

3) Finding two points adjacent to the peak point according to the sampling interval, and acquiring vector angles of the two points adjacent to the peak point and corresponding correlation coefficient values; as shown in fig. 2, in the present embodiment, two points adjacent to the peak point are set as the peak pointAnd，then isThe value of the correlation coefficient of the point,then isThe value of the correlation coefficient of the point;

4) and calculating to obtain a final direction-finding angle by a binomial curve fitting method according to the vector angle and the correlation coefficient value of the peak point and two adjacent points of the peak point.

In this example, the following binomial curve was usedCalculating the final direction finding result by a line fitting formula：

；

Wherein the content of the first and second substances,the vector angle corresponding to the peak point;the correlation coefficient value corresponding to the peak value point;andtwo points adjacent to the peak point respectively,is composed ofThe value of the correlation coefficient of the point,is composed ofThe value of the correlation coefficient of the point.

The embodiment is mainly improved for a direction finding algorithm and is suitable for single-channel, double-channel and multi-channel correlation interferometer systems. When correlation operation is carried out, the phase difference result is weighted by using amplitude information of signals received by the antenna elements, the correlation operation result is ensured to mainly depend on the antenna element with stronger receiving amplitude, and the influence of the antenna element with weak receiving signal amplitude on the correlation operation result is reduced, so that the direction finding precision under the weak signal condition is improved.

Example two

This embodiment provides a correlation interferometer direction-finding system for performing the correlation interferometer direction-finding method according to the first embodiment, which is spaced by an angleThe functions of each module of the direction-finding system are explained by taking the case that the direction-finding antenna array is composed of eight direction-finding oscillators and a central reference oscillator.

The direction-finding system mainly comprises the following modules: the device comprises a sample library module, a signal acquisition module, an amplitude phase calculation module, a correlation coefficient calculation module and an angle calculation module.

After the sample data collection is finished, the sample data can be directly used in subsequent direction finding without repeated acquisition. The sample data collection method in the sample library module comprises the following steps: the method comprises the steps of transmitting signals in a range of 360 degrees around an antenna at all angle intervals (0 degrees, 2 degrees and 4 degrees … … 358 degrees) in a standard field (a field with a wide reflection-free environment) in advance for each working frequency, recording phase difference vectors of all oscillators at each angle, and storing all phase difference data into a sample database module.

The sample data format for a certain operating frequency in the sample library is as followsWhereinIs an angleThe phase difference vector of the 8 antenna elements in angle is as follows:

。

the signal acquisition module is used for acquiring signals received by each measuring oscillator in the direction-finding antenna according to preset frequency.

The amplitude phase calculation module is used for calculating the received signal amplitude of each measuring oscillator and the phase difference vector between each measuring oscillator and the reference oscillator; the amplitude vector for recording the amplitude components of all the oscillators is(ii) a Phase difference vector formed by recording phase differences of all oscillators and reference oscillator。

The correlation coefficient calculation module is used for reading sample data corresponding to preset frequency from the sample library, performing weighting processing on the phase difference vector by using the signal amplitude, and performing correlation calculation by combining the sample data to obtain correlation coefficients corresponding to all angles; the method specifically comprises the following steps:

carrying out normalization operation on the amplitude, namely searching the maximum value of the amplitude of the measurement signal of each vibrator in the amplitude vector E, and recording the maximum value as Emax;

calculating a normalized magnitude vector:

。

reading the sample data of the frequency of the test from the sample library and recording the sample data as。

Is the phase difference vector at the i-th angular interval,

(ii) a And performing correlation coefficient operation according to the sample data and the phase difference vector obtained by testing, i-th angleThe correlation coefficient over the interval is calculated as follows:。

the angle calculation module is used for calculating the incoming wave direction of the signal according to the correlation coefficient corresponding to each angle so as to output a final direction finding result. The method specifically comprises the following steps:

searching for a peak value based on the correlation coefficient vectorTwo adjacent points areAndwherein(ii) a And performing binomial curve fitting on the obtained direction finding result to calculate a final direction finding result:

。

EXAMPLE III

The embodiment provides a correlation interferometer device, which comprises a processor, a memory and a computer program stored on the memory and capable of running on the processor, wherein the processor executes the computer program to realize the correlation interferometer direction finding method in the first embodiment; in addition, the present embodiment also provides a storage medium, on which a computer program is stored, and the computer program is executed to implement the above-mentioned correlation interferometer direction finding method.

The apparatus and the storage medium in this embodiment are based on two aspects of the same inventive concept, and the method implementation process has been described in detail in the foregoing, so that those skilled in the art can clearly understand the structure and implementation process of the system in this embodiment according to the foregoing description, and for the sake of brevity of the description, details are not repeated here.

The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.