Method based on linear programming for locating near-field targets and system thereof

Abstract

The invention provides a method based on linear programming for locating near-field targets and a system thereof, particularly a method for locating near-field targets on the basis of the compressivesensing theory. The method comprises the following steps: selecting a reference array element under the condition that the signal form is unknown, allowing the reference array element to work at the normal sampling frequency, and the other array elements to work at far below the Nyquist sampling frequency; taking the output signal of the reference array element as the reference target signal, to acquire the sample data of all the array elements; generating a time-delay table and a sparse basis array; generating a random mapping array and obtaining a coefficient array; obtaining a sparse vectorby linear programming solution; and acquiring the location information of the near-field target from the predetermined location-distance collection on the basis of the acquired estimation results ofthe sparse vector. According to the invention, the sensor does not need to work beyond the Nyquist sampling frequency, thereby greatly reducing the sampling rate, reducing the operating energy consumption of the sensor and improving the resource utilization rate of the system; and the method has no limits to the target bandwidth, so that the method is applicable to the target location of both narrowband and wideband, and the method is further applicable to non-Gaussian target location.

Description

technical field

[0001] The invention belongs to the field of array signal processing, in particular to a linear programming-based near-field target positioning method and system suitable for linear arrays. Background technique

[0002] A basic problem in array signal processing is target positioning, that is, to determine the parameters such as azimuth and distance of the space signal of interest. Target positioning refers to the use of a certain algorithm to process the two-dimensional space-time signal radiated or reflected by the array, so as to obtain the estimation of parameters such as target azimuth and distance. Generally speaking, target location assumes that the target is in the far-field condition, and the signal emitted by the source reaches the array in the form of a plane wave. However, when the target is in the near-field, that is, the distance between the target and the array is R<2L 2 / λ, where L is the effective aperture of the array, λ is the wavelengt...

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