A system and method for underchannel direction finding based on toeplitz matrix recovery

Abstract

The invention discloses a sub-channel direction finding system based on Toeplitz matrix restoration, the system includes a uniform line array containing M omnidirectional antennas, a P-channel receiver, P-1 multi-channel radio frequency switching switches, and a synchronous timing controller , a signal acquisition processor, and a spectrum estimation direction finding module. The steps of the method are: designing a switching mode of a multi-channel radio frequency switching switch so that it can gate the antenna elements in time; establishing a mathematical model for receiving signals of the gate antenna elements; calculating the covariance matrix of the signals received by the gate elements; According to the Toeplitz property of the uniform linear array covariance matrix, the covariance matrix corresponding to the entire array is recovered by using the covariance matrix calculated each time; according to the restored covariance matrix, the DOA estimation is performed using a covariance-based algorithm. The invention utilizes the characteristic of Toeplitz matrix, only needs to calculate the sub-covariance to restore the overall covariance, the complexity is low, and the physical hardware is easy to realize.

Description

technical field [0001] The invention belongs to the technical field of spatial spectrum estimation, and particularly relates to a suitable under-channel direction finding system and method when the number of receiver channels is less than the number of antennas. Background technique [0002] Direction Of Arrival (DOA) estimation is an important research direction in the field of array signal processing, and is widely used in radar positioning, tracking and other fields. Super-resolution direction finding technology has become a research hotspot in the field of spectrum monitoring direction finding due to its excellent performances such as high precision, high resolution and anti-multipath interference. At present, there are many super-resolution DOA estimation algorithms, such as multiple signal classification (MUltiple SIgnal Classification, MUSIC) algorithm, based on rotation invariance (Estimation of Signal Parameters via Rotational Invariance Techniques, ESPRIT) algorith...

AI Technical Summary

Problems solved by technology

However, this method has certain disadvantages: on the one hand, as the number of array elements increases, the number of receivers also increases correspondingly, which will make the cost of the receiving system very expensive, and the cost of system hardware becomes a constraint on application. A major factor; on the other hand, the increase in the number of channels makes it difficult to ensure consistency between the receivers of each channel, and the amplitude and phase errors between the channels will lead to a decrease in the direction finding performance of the algorithm

However, the single-channel direction-finding algorithm has high requirements on the performance indicators of the receiving channel, receiver and switch, and the calculation amount is large, and the direction-finding algorithm takes a lot of time, which affects the real-time performance of the system.

The weighted perturbation method can be applied to a single receiver system, and extended to the case of two-channel and three-channel receivers. The array covariance matrix recovery can be realized through appropriate weighting and weighted perturbation, but this method is difficult to implement in engineering, and in Adding precise perturbation to the RF section is difficult to control

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