Azimuth-equivalent delay difference passive positioning method ofdouble circular arrays

Abstract

The invention provides an azimuth-equivalent delay difference passive positioning method of double circular arrays. The method comprises the steps: firstly building a double-array space positioning model, and obtaining output data x1 (t) of each array element of two circular arrays, wherein l equals to1 and 2; calculating azimuth angles theta1 and theta2 of a target relative to the two array reference points by utilizing a spatial spectrum estimation algorithm; calculating a time delay difference tauij between the ith array element of the circular array 1 and the jth array element of the circular array 2 by using a time delay estimation algorithm, and calculating an equivalent time delay difference taue by using the tauij; and substituting the azimuth angles theta1 and theta2 and the equivalent delay difference taue into an azimuth-equivalent delay difference positioning formula, and obtaining a distance R1R2 from the target to each array reference point and a coordinate position coordinate (xs, ys) of the target. Reference array elements are prevented from being added to a center of the uniform circular array, an array structure is simplified, system cost is saved, meanwhile, array redundant information is utilized, time delay estimation precision is improved, and then target positioning precision is increased.

Description

technical field [0001] The invention relates to an azimuth-equivalent time delay difference passive positioning method of a double circular array, which belongs to the field of target passive positioning. Background technique [0002] According to the different types of information used, dual-array passive positioning technology can be divided into pure azimuth positioning and azimuth-delay difference positioning methods. In the azimuth-only positioning method, the two arrays calculate the azimuth angle of the same target respectively, and use the triangular relationship to estimate the distance, and then obtain the target position coordinates. The azimuth cross positioning has a wide range of applications, but the positioning error is very sensitive to the azimuth accuracy. [0003] The azimuth-delay difference positioning method is an improved algorithm for azimuth cross positioning, which utilizes the spatial coherence between the two array elements. When the coherence ...

AI Technical Summary

Problems solved by technology

[0008] When the traditional azimuth-delay positioning method calculates the delay difference information, it only uses the received data of the array elements at the reference position of the array, and does not use all the array element data of the array, which makes the delay difference estimation results extremely susceptible to noise interference, which in turn affects positioning accuracy

In terms of array structure, for a special array structure such as a uniform circular array, a reference array element is usually added at the center of the array when the delay difference is estimated, which greatly increases the complexity of the equipment and the cost of the system.

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