Bistatic MIMO radar high-speed target across-range-gate speed measuring and positioning method

Abstract

The invention belongs to the technical field of radar signal processing, and discloses a bistatic MIMO radar high-speed target across-range-gate speed measuring and positioning method. The method comprises the following steps: acquiring L baseband echo pulse signals; compressing the pulse of the L baseband echo pulse signals to get pulse output signals, and estimating the rough estimated values of the launch azimuth angle, launch pitch angle and reception pitch angle of a target; determining the number of range gates spanned by the target based on the rough estimated values of the angles of the target; estimating the angle information and Doppler frequency of the target based on the number of range gates spanned by the target; and determining the coordinate information of the target based on the angle information of the target, and determining the speed of the target based on the Doppler frequency of the target. Under the condition that a radar target has range migration, the angle information and Doppler frequency of the radar target can be estimated accurately, and the radar target can be positioned accurately.

Description

technical field [0001] The invention relates to the technical field of radar signal processing, in particular to a speed measurement and positioning method for a bistatic MIMO radar high-speed target across a range gate. Background technique [0002] The speed of modern aircraft is getting faster and faster. At present, countries all over the world are developing supersonic aircraft, represented by the X-43A test aircraft developed by the United States. Its speed reaches Mach 9.7, which poses a challenge to the traditional system of radar target detection. [0003] In recent years, in order to improve the detection performance and estimation accuracy of radar, people have widely applied Multiple-Input Multiple-Output (MIMO) technology to radar, and obtained MIMO radar. Each array element of the MIMO radar transmits orthogonal signals, and the receiving array separates the signals of each transmitting channel through a matched filter method, so a virtual 3-array can be formed...

AI Technical Summary

Problems solved by technology

At present, a number of robust, real-time and efficient multi-target positioning methods have emerged. However, the existing algorithms are all aimed at stationary targets or low-speed targets, and do not involve high-speed moving targets, such as high-speed flying missiles in the air defense field, in Orbital targets in the aerospace field, etc.

Since the high-speed moving target will move across multiple range units during the echo accumulation time, that is, the high-speed moving target has crossed multiple range units during the angle estimation process. However, the existing angle estimation algorithms for bistatic MIMO radars cannot Echo accumulation is carried out across distance units, so it is difficult to effectively estimate the parameters such as DOD and DOA of high-speed moving targets in space

[0004] In response to this problem, Chen Jinli et al. proposed a method for estimating parameters such as distance and angle of high-speed moving targets in single-base MIMO radar. This method performs coherent combination of multiple output channel echo data in a short time to replace the echo data. Long-term coherent accumulation detection to reduce the impact of distance migration on target detection, and can effectively achieve unambiguous detection of multiple high-speed moving targets, but this method requires a large number of antenna elements to obtain high spatial synthesis gain

In addition, Chen Baixiao et al. proposed to apply multi-carrier frequency MIMO radar to multi-dimensional parameter estimation of high-speed targets, use cascaded Keystone transform to correct range walk, and compensate for the difference of each separate channel caused by transmitting multi-carrier frequency signals. Doppler frequency difference, thus solving the multi-dimensional parameter estimation of multi-carrier frequency MIMO radar under high-speed moving target, but the Keystone transform will fail when the target appears Doppler ambiguity, and the high-speed movement of the target will inevitably appear Doppler ambiguity, so The Doppler ambiguity factor of the target needs to be known in advance and compensated for

In addition, since the multi-carrier frequency MIMO radar uses frequency-division transmission signals to separate the transmission channels, the total transmission signal bandwidth of the radar will be very large, which will increase the complexity of hardware implementation

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