A phase difference change rate positioning method based on a uniform circular array

Abstract

The application discloses a phase difference change rate positioning method based on a uniform circular array, first, data collection of a radiation source signal is completed by using the uniform circular array, Fourier transform is performed on two array element received signals by a frequency domain phase discrimination method, a spectrum peak position of a correlation spectrum Y(omega) is calculated, and a phase value at the position is obtained, which is a fuzzy baseline phase difference; then, all fuzzy numbers are traversed, a similarity calculation method is used, circular array defuzzification is realized, a whole week fuzzy influence generated in the phase discrimination process is removed, and a non-fuzzy phase difference of each baseline is obtained, finally, a baseline group with a 0 array element as a center array element is set as a basic group, each array element of the circular array is traversed, positioning results of different baseline groups are obtained respectively, each group of results is weighted based on a phase difference change rate, and finally, a spatial position of a radiation source is obtained; the algorithm is improved for a detection array, the whole detection is completed by using the uniform circular array, and the omnidirectional detection capability of the algorithm is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radiation source positioning, and in particular to a phase difference change rate positioning method based on a uniform circular array. BACKGROUND

[0002] Traditional single-station passive positioning technology mostly uses direction finding results to obtain the position of the radiation source, and positioning is achieved by detecting the angle of arrival of the radiation source at different positions. Although this method is simple to implement, it has the disadvantages of low positioning accuracy and slow positioning speed. With the development of technology, researchers have paid attention to passive positioning methods based on kinematic principles. Typical methods use parameters such as time of arrival and Doppler frequency shift, and combine corresponding filtering approximation methods to achieve positioning of the radiation source. However, such methods have high requirements for target characteristics, time measurement resolution, and frequency of measuring equipment, which objectively increases the difficulty of measurement implementation. Single-station passive positioning technology based on phase difference change rate obtains baseline phase difference and its change rate data by tangential motion of the radiation source, solves the distance between the moving single-station and the radiation source, and calculates the geometric position of the radiation source. This method has the characteristics of simple equipment, fast positioning speed, and high positioning accuracy, and has broad application prospects.

[0003] Qi Liang in his published paper "Positioning Method of Single Baseline Interferometer Based on Time Difference Direction Finding and Phase Difference Change Rate" (2021 IEEE 4th Advanced Information Management, Communicates, Electronic and Automation Control Conference (IMCEC), 2021) discloses an interferometer positioning method based on time difference direction finding combined with phase difference change rate. This method first obtains the angle of arrival of the radiation source through time difference direction finding, then uses a single baseline interferometer to obtain phase difference and phase difference change rate data, then brings the angle of arrival into the phase difference and phase difference change rate to obtain unambiguous phase difference and corresponding phase difference change rate, and finally calculates the distance between the detection array and the radiation source, and obtains the geometric coordinates of the radiation source through coordinate conversion. Compared with traditional methods, this method does not require long search and accumulation, and has faster positioning speed.

[0004] Zhang Hui in his published paper "Algorithm of Passive Location of Airborne for Communication Station (Fixed Radiating Source Target Single Machine Passive Location Method)" (Communications Technology, 2021) discloses a phase difference rate positioning method combined with Kalman filtering. The method first obtains the phase difference information using a single baseline, then uses the Kalman filtering algorithm to smooth filter it, uses the smoothed phase difference data to solve the phase difference rate, then solves the distance between the detection array and the radiating source, and finally obtains the geometric coordinates of the radiating source through coordinate conversion. Compared with the traditional method, the method is less affected by noise, has higher positioning accuracy and stronger adaptability.

[0005] However, the above-mentioned prior art generally uses a double array as a detection array, and detects the phase difference by placing the antenna elements on the front and back of the moving platform. Although the correct positioning of the radiating source can be achieved, the phase difference rate of the process is easily affected by the incoming wave angle, resulting in different precision of the positioning results for different incoming wave directions, and the omnidirectional detection capability of the positioning algorithm has defects. At the same time, when the double array is used as the detection array, the amount of information read is less, and the overall system information utilization capability is weak, which makes it easy to be affected by noise and other factors, and it is difficult to cope with complex electromagnetic environment. In addition, there is still a problem of phase ambiguity in the prior art, which greatly limits the application range of the algorithm. SUMMARY

[0006] The purpose of the present application is to solve the above-mentioned problems. The present application provides a phase difference rate positioning method based on a uniform circular array, which improves the omnidirectional detection capability of the algorithm by improving the detection array and using a uniform circular array for overall detection.

[0007] The technical scheme adopted by the present application is as follows:

[0008] A phase difference rate positioning method based on a uniform circular array, which is implemented according to the following steps:

[0009] Step 1, phase demodulation;

[0010] The spectrum peak position of the correlation spectrum is obtained by receiving the signal of the array element, the baseline phase difference is determined by the phase value of the spectrum peak position, the baseline length is calculated according to the number of elements of the uniform circular array, the relationship between the baseline length and the frequency of the radiating source is judged, the existence of phase ambiguity is determined, then the range of the existing ambiguity number is obtained, and then the non-ambiguous phase difference of each baseline is obtained by traversing the ambiguity number;

[0011] Step 2, phase difference rate positioning based on cross baseline;

[0012] The antenna array is divided according to its elements. The uniform circular array is traversed, and each element is set as the center element. Each element is combined with its two neighboring elements to form an antenna group. The two short baselines formed by the center element and its neighboring elements constitute a baseline pair. The phase difference and phase difference change rate of each baseline pair are determined. The data of each test group are solved based on the phase difference and phase difference change rate data to obtain several sets of positioning results.

[0013] Step 3: Finally, weight the several sets of positioning results obtained in Step 2.

[0014] Furthermore, the specific method for determining the baseline phase difference in step 1 is as follows:

[0015] Using frequency domain phase detection, firstly, Fourier transforms are performed on the received signals x1(t) and x2(t) of the two array elements to obtain F1(ω) and F2(ω), and then their correlation spectrum Y(ω) = F1(ω)·F2(ω) is calculated. * The position of the spectral peak, and the phase value at that point is the baseline phase difference:

[0016] φ=2πfΔt=angle[Y(ω)| ω＝2πf (1)

[0017] In the formula, f represents the radiation source frequency, and Δt is the time delay.

[0018] Furthermore, the specific method for calculating the length of each baseline in step 1 is as follows:

[0019] Calculate the length d of each baseline based on the number of elements in the uniform circular array:

[0020]

[0021] In the formula, M is the number of elements in the circular array, R is the radius of the elements, and h represents the number of spacing elements between the two elements at the baseline. When M is odd, When M is even

[0022] Further, in step 1, the relationship between the baseline length and the radiation source frequency is determined to confirm the existence of phase ambiguity. Then, the range of existing ambiguity numbers is obtained, and the ambiguity numbers are iterated through. The specific method is as follows:

[0023] When the ratio of the baseline length d to the radiation source frequency f is less than or equal to 1 / 2, there is no phase ambiguity in the baseline phase difference, and positioning can be performed directly. When the ratio of the baseline length d to the radiation source frequency f is greater than 1 / 2, there is phase ambiguity in the baseline phase difference. The integer ambiguity number k of the baseline is introduced for resolution, and its maximum value is calculated as follows:

[0024]

[0025] The range of the value of the fuzzy number is:

[0026] k∈[-k max ,k max ](4)

[0027] Then, by traversing the fuzzy number, the fuzzy integer period is added to the baseline phase difference calculation formula, all unambiguous phase differences are listed, the similarity between the unambiguous phase differences and the true phase difference is calculated, the fuzzy number corresponding to the result with the highest similarity is selected as the actual fuzzy number, the fuzzy integer period is compensated to the measured phase difference, and the unambiguous phase difference of each baseline is obtained.

[0028] Further, the specific way of positioning the phase difference change rate based on the cross baseline in step 2 is:

[0029] The M-element uniform circular array is divided into M baseline groups, and the unambiguous baseline phase difference corresponding to each baseline group is φ pm , φ qm , and the phase difference change rate is

[0030] The specific positioning is implemented in the following steps:

[0031] Step 2.1, obtain the azimuth angle change rate, select the baseline group, detect the phase difference of the baseline group, obtain the phase difference change rate through the phase difference, then obtain the theoretical value of the phase difference change rate, and obtain the azimuth angle change rate and the pitch angle change rate data through the theoretical value of the phase difference change rate;

[0032] Step 2.2, calculate the actual phase difference change rate by difference method;

[0033] Step 2.3, solve the radiation source position coordinates through the data obtained in steps 2.1 and 2.2.

[0034] Further, step 2.1 is as follows:

[0035] The grouping strategy based on the cross baseline is used to complete the selection of the baseline group, and the detected baseline group is set to (pm), (qm); the phase difference of the detected baseline group is:

[0036]

[0037] In the formula,

[0038] By simultaneously solving φ pm and φ qm corresponding to the equation, the following calculation formula is obtained:

[0039]

[0040] By converting the formula, the trigonometric function values ​​of the direction-finding angles corresponding to the baseline group centered at m are obtained:

[0041]

[0042]

[0043] Differentiate both sides of the equation for the phase difference of the detection baseline group to obtain the rate of change of phase difference between the radiation source signals received by the unit antenna. Then, substitute the trigonometric function values ​​of the direction finding angles corresponding to the baseline group with m as the center element into the equation to obtain the theoretical value of the rate of change of phase difference.

[0044]

[0045] in,

[0046]

[0047] Transform the theoretical formula for the rate of change of phase difference to obtain the data for the rate of change of azimuth and the rate of change of elevation:

[0048]

[0049] Furthermore, step 2.2 is detailed as follows:

[0050] Suppose that a phase difference sequence {φ1, φ2, ..., φ3} is obtained after N observations. N}, where the time interval between each observation is T, and the phase difference transformation rate at time iT is approximated by the average rate of change of the phase difference during the time interval from time (i-1)T to time iT:

[0051]

[0052] Obtaining the true phase difference rate of change using the finite difference method

[0053] Furthermore, step 2.3 is detailed below:

[0054] Determine the distance between the detection array and the radiation source:

[0055] Based on the spatial relationship between the radiation source and the detection array:

[0056]

[0057] In the formula, It is the detected azimuth angle at time t, (X T ,Y T Z T (x) represents the location coordinates of the radiation source. oi (t),yoi (t),z oi (t)) is the position coordinate of the detection array at time t;

[0058] The derivative of the above formula is calculated to obtain the distance r between the detection array and the radiation source:

[0059]

[0060] In the formula, is the moving speed of the detection array in the X-axis direction, is the moving speed of the detection array in the Y-axis direction;

[0061] The trigonometric function value of the calculated direction-finding angle is transformed to return the numerical value from the basic group to the actual detection group:

[0062]

[0063] The calculated azimuth angle change rate The moving speed of the detection array in the X-axis direction The moving speed of the detection array in the Y-axis direction is brought into the distance calculation between the detection array and the interference source to obtain the specific value of r;

[0064] The position coordinate of the radiation source is obtained:

[0065] After the detection array completes the above measurement and calculation, the polar coordinate position of the radiation source target in the polar coordinate with the position point of the detection array itself as the coordinate origin and the motion direction as the zero-degree direction is obtained On this basis, through coordinate transformation, the position coordinate (X T ,Y T ,Z T ) of the radiation source in the three-dimensional space is finally obtained, as follows:

[0066]

[0067] The transformation can be obtained as follows:

[0068]

[0069] Further, the following formula (22) is used in step 3 to weight process the positioning results obtained in step 2; the greater the phase difference change rate value, the greater the error tolerance, so that when the error is constant, the baseline group with the greater phase difference change rate has the stronger error tolerance, and therefore the weight calculation formula in the weighting process is as follows:

[0070]

[0071] In conclusion, by using the above technical solutions, the present application has the following advantages:

[0072] 1. The improved method based on the uniform circular array replaces the original array with a uniform circular array, reduces the influence of the incoming wave angle on the phase difference change rate, and improves the omnidirectional detection capability of the algorithm.

[0073] 2. The present application improves the expansion capability of the array by combining baseline grouping and positioning result weighting, divides different baseline pairs into groups to solve the positioning result, and modularizes the algorithm. At the same time, the array element number is easy to increase, so that it is not limited to a specific uniform circular array with a certain number of elements. At the same time, the positioning results calculated by each baseline group are weighted, which weakens the influence of noise and other factors, improves the data utilization capability, reduces the overall complexity of the algorithm, and enhances the robustness of the algorithm.

[0074] 3. The present application solves the ambiguity of the phase difference by traversing the ambiguous number, so that the algorithm has the positioning capability of high-frequency signals, and greatly improves the application range of the algorithm. BRIEF DESCRIPTION OF DRAWINGS

[0075] Figure 1 is a flowchart of a phase difference change rate positioning method based on a uniform circular array of the present application;

[0076] Figure 2 is a geometric structure diagram of a uniform circular array in the method of the present application;

[0077] Figure 3 is a flowchart of positioning based on cross baseline in the method of the present application;

[0078] Figure 4 is a cross baseline grouping strategy diagram in the method of the present application. DETAILED DESCRIPTION

[0079] The present application will be described in detail below with reference to the accompanying drawings.

[0080] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0081] EMBODIMENT

[0082] In this embodiment, a phase difference change rate positioning method based on a uniform circular array is shown in Figure 1 The specific implementation is as follows:

[0083] Step 1 of the embodiment is to use a uniform circular array to complete data acquisition of a radiation source signal, to perform Fourier transform on two-array element received signals by a frequency domain phase discrimination method, to obtain a spectrum peak position of a correlation spectrum Y(ω) of the two-array element received signals, and to obtain a phase value at the spectrum peak position as a fuzzy baseline phase difference; to traverse all fuzzy numbers, to remove a whole cycle fuzzy influence generated in a phase discrimination process by using a similarity calculation method to realize circular array de-fuzzing, and to obtain a non-fuzzy phase difference of each baseline, as follows:

[0084] (1) Phase de-fuzzing

[0085] By a frequency domain phase discrimination method, Fourier transform is first performed on two-array element received signals x1(t), x2(t) to obtain F1(ω), F2(ω), and then a spectrum peak position of a correlation spectrum Y(ω)=F1(ω)·F2(ω) is obtained, and a phase value at the spectrum peak position is a baseline phase difference: *

[0086] φ=2πfΔt=angle[Y(ω) ω＝2πf ] (1)

[0087] In the formula, f represents a radiation source frequency, that is, an accepted signal frequency, and Δt is a time delay.

[0088] According to the number of array elements of the uniform circular array, the length d of each baseline is calculated:

[0089]

[0090] In the formula, M is the number of array elements of the circular array, R is the radius of the array element, and h represents the number of interval array elements of the two array elements of the baseline. When M is an odd number, when M is an even number,

[0091] When the ratio of the baseline length d to the radiation source frequency f is less than or equal to 1 / 2, the baseline phase difference does not exist phase ambiguity, and positioning can be directly performed at this time. When the ratio of the baseline length d to the radiation source frequency f is greater than 1 / 2, the baseline phase difference exists phase ambiguity, and a whole cycle fuzzy number k possibly existing in the baseline is introduced for calculation, and the maximum value is calculated as:

[0092]

[0093] The specific fuzzy number value range is:

[0094] k∈[-k max ,k max ](4)

[0095] ​By traversing the fuzzy number, fuzzy integer period is added to the baseline phase difference calculation formula, all possible unambiguous phase differences are listed, the similarity between the unambiguous phase difference and the true phase difference is calculated, the fuzzy number corresponding to the highest similarity result is selected as the actual fuzzy number, the fuzzy integer period is compensated to the measured phase difference, and the unambiguous phase difference of each baseline is obtained.

[0096] In this embodiment, as shown in the step 2, the baseline group with the center array element as the fixed array element is the basic group, each array element of the circular array is traversed to obtain the positioning result of different baseline groups: Figure 3

[0097] According to the division of the antenna array elements, the uniform circular array is traversed, the circular array elements are sequentially set as the center array elements, and the two adjacent array elements are combined to form an antenna group, so that the two short baselines composed of the center array element and the adjacent array elements form a baseline pair; through the above idea, the M-element uniform circular array is divided into M baseline groups, and the unambiguous baseline phase difference corresponding to each baseline group is φ pm , φ qm , and the phase difference change rate is According to the phase difference and the phase difference change rate data, the data of each test group is solved to obtain M positioning results; the specific steps are as follows:

[0098] Step 2.1, the azimuth change rate is obtained.

[0099] The grouping strategy based on the cross baseline is used to complete the baseline group selection, and the detected baseline groups are (pm) and (qm). The phase difference of the detected baseline group is:

[0100]

[0101] In the formula,

[0102] By simultaneously solving the equations corresponding to φ pm and φ qm , the following calculation formula is obtained:

[0103]

[0104] Through formula conversion, the trigonometric function value of the direction finding angle corresponding to the baseline group with m as the center array element is obtained:

[0105]

[0106]

[0107] ​By differentiating both sides of the equation for the phase difference of the detection baseline group, the rate of change of phase difference between the radiation source signals received by the unit antenna can be obtained. Then, by substituting the trigonometric function values ​​of the direction finding angles corresponding to the baseline group with m as the center element, the theoretical value of the rate of change of phase difference can be obtained.

[0108]

[0109] in,

[0110]

[0111] Transform the theoretical formula for the rate of change of phase difference to obtain the data for the rate of change of azimuth and the rate of change of elevation:

[0112]

[0113] Step 2.2: Calculate the actual phase difference rate of change using the finite difference method;

[0114] Suppose that a phase difference sequence {φ1, φ2, ..., φ3} is obtained after N observations. N}, where the time interval between each observation is T, and the phase difference transformation rate at time iT is approximated by the average rate of change of the phase difference during the time interval from time (i-1)T to time iT:

[0115]

[0116] Obtaining the true phase difference rate of change using the finite difference method

[0117] Step 2.3: Calculate the coordinates of the radiation source location;

[0118] Determine the distance between the detection array and the radiation source;

[0119] Based on the spatial relationship between the radiation source and the detection array, we can obtain:

[0120]

[0121] In the formula, It is the detection azimuth angle at time t, (X T ,Y T Z T (x) represents the location coordinates of the radiation source. oi (t),y oi (t),z oi (t) represents the position coordinates of the detection array at time t;

[0122] Taking the derivative of the above equation, we can obtain the distance r between the detection array and the radiation source:

[0123]

[0124] In the formula, is the moving speed of the detection array in the X-axis direction, is the moving speed of the detection array in the Y-axis direction;

[0125] The trigonometric function value of the calculated direction finding angle is transformed to return the value from the basic group to the actual detection group:

[0126]

[0127] Finally, the calculated azimuth angle change rate The moving speed of the detection array in the X-axis direction The moving speed of the detection array in the Y-axis direction is brought into the distance calculation between the detection array and the interference source, and the specific value of r is obtained;

[0128] The position coordinates of the radiation source are obtained:

[0129] After the detection array completes the above measurement and calculation, the polar coordinate position of the radiation source target in the polar coordinate with the position point of the detection array itself as the coordinate origin and the motion direction as the zero-degree direction is actually obtained On this basis, through coordinate conversion, the position coordinates (X T , Y T , Z T ) of the radiation source in the three-dimensional space can be finally obtained, as follows:

[0130]

[0131] Conversion can obtain:

[0132]

[0133] The method of the present application uses the baseline grouping method to determine the position of the radiation source, improves the expansion ability of the number of array elements, so that the algorithm of the present application is not limited to a circular array with a specific number of array elements, and with the increase of the number of array elements, the noise suppression effect of the algorithm will be stronger, and the algorithm will have higher positioning performance.

[0134] As shown in Figure 4 , the specific implementation of the baseline group selection strategy method of the embodiment is: traversing each array element of the circular array, setting the baseline group with array element 0 as the center array element as the basic group for calculation, and setting the detected baseline group as (pm), (qm), wherein m corresponds to the center array element of the current baseline group, and the value range is 0-M-1.

[0135] The baseline group phase difference with array element 0 as the center array element is:

[0136]

[0137] The phase difference corresponding to the detection baseline group with the basic group as the detection template is:

[0138]

[0139] The embodiment uses a cross short baseline as a detection baseline group, avoids the problem of reduced signal detection capability of a specific direction for a parallel baseline, improves the omnidirectional detection capability of the algorithm, and expands the analysis of the detection baseline group based on the basic group as a reference, standardizes the grouping form, reduces the introduction of medium-long baselines and long baselines, and reduces the expansion complexity of the algorithm.

[0140] Step 3, weighting the positioning result to obtain the final spatial position of the radiation source;

[0141] The greater the phase difference change rate value, the greater the error tolerance, so when the error is constant, the greater the phase difference change rate of the baseline group, the stronger the error tolerance. According to the above principle, the positioning results obtained by each baseline group are weighted, and the weight value is calculated as:

[0142]

[0143] Using a single baseline or orthogonal baseline group to obtain the phase difference change rate can also realize radiation source positioning, but due to the limitation of the number of array elements and the directionality of the array, the positioning capability for a specific direction of the radiation source signal will sharply decrease, and due to the insufficient information utilization, the overall detection is limited to the specific environment, and the application capability is low in harsh environment. Using the positioning method based on the uniform circular array, the number of array elements is expanded, the information utilization capability of the algorithm is improved, and the algorithm has strong robustness. At the same time, the structure of the uniform circular array also ensures that it has good detection capability for signals in all directions.

[0144] As Figure 2 shown is the geometric structure of the M-element uniform circular array in the embodiment, and the phase difference of each baseline is:

[0145] The array element radius is R, wherein θ are the azimuth angle and the elevation angle, respectively, the time to the reference point is ahead of the time of the incident signal received by the array element m, and then the time delay τ m of the array element m relative to the reference point is:

[0146]

[0147] The phase shift of a single array element relative to the center of the circular array is:

[0148]

[0149] where m = 0, 1,..., M-1, f is the frequency, c is the signal propagation speed; the inter-element phase difference is:

[0150]

[0151] The principles and implementation manners of the present application are described herein by using specific examples, and the above example descriptions are only used to help understand the method of the present application and its core idea. It should be noted that, for ordinary skilled in the art, without departing from the principles of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A phase difference rate of change positioning method based on a uniform circular array, characterized in that, The method is implemented according to the following steps: Step 1, phase unblurring; The data acquisition of the radiation source signal is completed by using a uniform circular array, the spectrum peak position of the correlation spectrum is obtained by receiving the signal of the array element, the baseline phase difference is determined by the phase value of the spectrum peak position, the length of each baseline is calculated according to the number of array elements of the uniform circular array, the relationship between the baseline length and the radiation source frequency is judged, the existence of phase ambiguity is determined, then the range of the existing ambiguity number is obtained, then the ambiguity number is traversed to obtain the unambiguous phase difference of each baseline; Step 2, phase difference rate positioning based on cross baseline, the specific way is as follows: The M-element uniform circular array is divided into M baseline groups, and the unambiguous baseline phase difference corresponding to each baseline group is 、 , and the phase difference change rate is 、 ; The specific positioning is implemented according to the following steps: Step 2.1, obtain the azimuth rate, select a baseline group, detect the phase difference of the baseline group, obtain the phase difference rate through the phase difference, then obtain the theoretical value of the phase difference rate, and then obtain the azimuth rate and the pitch angle rate data through the theoretical value of the phase difference rate; Step 2.2, calculate the actual phase difference rate by difference method; Step 2.3, solve the radiation source position coordinates by the data obtained by step 2.1 and step 2.2; Step 3, finally, the several positioning results obtained in step 2 are weighted processed.

2. The phase difference rate of change positioning method based on the uniform circular array according to claim 1, characterized in that, The specific way of determining the baseline phase difference in step 1 is: The frequency domain phase detection method is used to first analyze the received signals of the two array elements. , Fourier transform to obtain , Then calculate its related spectrum. The position of the spectral peak, and the phase value at that point is the baseline phase difference: （1） wherein denotes the frequency of the radiation source, is the time delay.

3. The phase difference rate of change positioning method based on the uniform circular array according to claim 1, wherein, The specific way of calculating the length of each baseline in step 1 is: According to the number of elements of the uniform circular array, the length of each baseline is calculated : （2） wherein is the number of elements of the circular array, is the radius of the elements, h represents the number of elements separating the two elements of the baseline, when is odd, when is even, .

4. The phase difference rate of change positioning method based on the uniform circular array according to claim 2 or 3, characterized in that, The specific way of judging the relationship between the baseline length and the radiation source frequency, determining the existence of phase ambiguity, then obtaining the range of the existing ambiguity number, then traversing the ambiguity number is: When the baseline length is less than or equal to 1 / 2 of the ratio of the radiation source frequency , the baseline phase difference does not have phase ambiguity, and positioning can be directly performed; when the baseline length is greater than 1 / 2 of the ratio of the radiation source frequency , the baseline phase difference has phase ambiguity, and the whole-ambiguity number existing in the baseline is introduced to solve, and the maximum value is calculated as: （3） The specific range of the existing ambiguity number is: （4） Then, by traversing the ambiguity number, the ambiguity whole period is added to the baseline phase difference calculation formula, all unambiguous phase differences are listed, the similarity between the unambiguous phase difference and the real phase difference is calculated, the ambiguity number corresponding to the highest similarity result is selected as the actual ambiguity number, the ambiguity whole period is compensated to the measured phase difference, and the unambiguous phase difference of each baseline is obtained.

5. The phase difference rate of change positioning method based on the uniform circular array according to claim 1, wherein, The specific way of step 2.1 is as follows: The baseline group selection is completed using a cross-baseline-based grouping strategy, and the baseline group for detection is set as , ; the phase difference of the baseline group for detection is （5） （6） wherein, , , represents the number of whole ambiguities present at the baseline, , are azimuth, elevation, respectively, is the signal propagation velocity, is the frequency of the radiation source, is the array element radius; simultaneously and Corresponding equations give the following calculation formula: （7） By formula conversion, it is obtained that the trigonometric function value of the direction finding angle corresponding to the baseline group of the central array element is ​ （8） （9） （10） （11） （12） The phase difference formula of the baseline group is differentiated on both sides to obtain the rate of change of the phase difference between the signals received by the unit antennas. The trigonometric function value corresponding to the direction finding angle of the baseline group centered on the array element is then substituted to obtain the theoretical value of the rate of change of the phase difference. m The trigonometric function value corresponding to the direction finding angle of the baseline group centered on the array element is then substituted to obtain the theoretical value of the rate of change of the phase difference. （13） Wherein, （14） The azimuth rate and the pitch angle rate data are obtained by transforming the phase difference rate theoretical formula: （15）。 6. The phase difference rate of change positioning method based on a uniform circular array according to claim 1, wherein, The specific way of step 2.2 is as follows: Let us assume that a sequence of phase differences is obtained by each observation is separated by the phase difference at time is approximated by the average rate of change of the phase difference over the time interval from to . （16） Obtaining real phase difference change rate using differential method , .

7. The phase difference rate of change positioning method based on the uniform circular array according to claim 5, characterized in that, The specific way of step 2.3 is as follows: The distance between the detection array and the radiation source is obtained: According to the spatial position relationship between the radiation source and the detection array: （17） wherein is the detected azimuth angle at the time instant, is the position coordinate of the radiation source, is the position coordinate of the detection array at the time instant, is the position coordinate of the detection array at the time instant, Taking the derivative of the above equation, the distance between the array and the source is obtained : （18） In the formula, , is the moving speed of the detection array in the X-axis direction, is the moving speed of the detection array in the Y-axis direction; The trigonometric function value of the calculated direction finding angle is transformed, so that the numerical value is converted from the basic group to the actual detection group: （19） The calculated azimuth angle change rate , the moving speed of the detection array in the X-axis direction , the moving speed of the detection array in the Y-axis direction into the distance calculation between the detection array and the interference source, to obtain the specific numerical value; The position coordinates of the radiation source are obtained: After the detection array completes the above measurement and calculation, the polar coordinate position of the radiation source target in the polar coordinate with the position point of the detection array itself as the coordinate origin and the motion direction as the zero-degree direction is obtained On this basis, through coordinate conversion, the position coordinates of the radiation source in the three-dimensional space are finally obtained As follows: （20） The conversion can be obtained: （21）。 8. The phase difference rate of change positioning method based on the uniform circular array according to claim 1, wherein, In step 3, the several positioning results obtained in step 2 are weighted processed by using formula (22); the weight calculation formula in the weighting process is as follows: （22）。

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