Airborne single-station passive positioning method for multiple broadband targets

Abstract

The invention discloses an airborne single-station passive positioning method for multiple broadband targets and mainly solves the problem that multiple broadband radiation source targets cannot be subjected to single-station passive positioning in the prior art. The method comprises the following implementation steps: (1) sampling a far-field broadband radiation source signal at the receiving end to obtain an observation signal; (2) performing band narrowing on a broadband observation signal received by an array element through FRFT; (3) building a signal vector I(k) of a k-th signal in an FRFT domain; (4) obtaining a time average autocorrelation matrix for the k-th signal by utilizing the signal vector I(K), and performing eigen value decomposition; (5) building a guide matrix in a distance form of the k-th signal; (6) performing sampling at the receiving end for L times, repeatedly executing the steps of (2) to (5), and searching a target function for a maximum value, wherein (xk,yk,zk) corresponding to a maximum value point serves as the coordinates of a target k. According to the airborne single-station passive positioning method for the multiple broadband targets, the multiple broadband radiation source targets can be subjected to single-station passive positioning. The method can be used for detecting and reconnoitering an unmanned flight platform and a manned flight platform.

Description

technical field [0001] The invention belongs to the technical field of radar, and in particular relates to a broadband multi-target airborne single-station passive positioning method, which can be used for passive positioning of multi-radiation source targets in the fields of electronic reconnaissance monitoring and long-distance early warning detection. Background technique [0002] Active equipment such as radar, sonar, etc., actively emit electromagnetic wave signals and receive echo signals reflected from targets. The echo signals contain target position information, and further calculations can achieve target positioning. This method of achieving target positioning by emitting electromagnetic signals from the equipment itself is called active positioning. Compared with active positioning, passive positioning, which does not actively transmit signals but passively receives one-way target radiation source signals, has the advantages of long range and strong concealment, a...

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Problems solved by technology

For example, Zhang Min, Guo Fucheng, and Zhou Yu, "Direct positioning of a moving single station based on a single long-baseline interferometer", Acta Aeronautica Sinica, 2013, 34(2), pp.378-386, proposed to give Multiple positioning circles are used to solve the target position and achieve unambiguous positioning. However, in order to improve the convergence speed, in addition to strong maneuverability, certain requirements are also placed on the motion attitude of the observation station, so that there are obvious differences between the positioning line clusters, otherwise A number of fuzzy positioning areas will be formed; some scholars use filtering algorithms and cost functions to solve positioning fuzzy, for example, Guo Fucheng, Jia Xingjiang, Huang Fukan, "Airborne single-station passive positioning method and its Error Analysis", Acta Aeronautics Sinica, 2009, 30(6), pp.1090-1095, proposed to use nonlinear tracking filter methods such as least squares and extended Kalman (EKF) to solve the target position, but the algorithm needs to be given The selection of the initial value and its estimation accuracy directly affect the positioning result

The above traditional positioning methods need to estimate single or multiple parameters first, and then solve the positioning cost function. The positioning parameters are related to the frequency of the target radiation source, and have high requirements for the directivity and change rate of the antenna. At the same time, the mobility of the observation station There are also many restrictions in terms of motion and attitude; in addition, the targeted radiation source signals are all narrowband, which is not applicable to broadband scenarios

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