A Maximum Likelihood Target DoA Estimation Method Based on Joint Processing of Multiple Wavepoints

Abstract

The invention discloses a maximum likelihood target DOA (Direction of Arrival) estimation method based on multi-wave potential combined treatment, comprising the steps of: (1) obtaining the radar echo data of M wave potentials, and respectively performing pulse Doppler treatment to obtain the data of Doppler channels where the targets of the M wave potentials are located; (2) respectively estimating the covariance matrix of the M wave potentials; (3) uniformly dividing the angle scope corresponding to the main wave beam of an [m / 2]th wave potential into K-1 parts to obtain K target azimuth angles; and calculating the airspace steering vector S(theta i) of an ith target azimuth angle theta i; (4) calculating the weight vector Wim of an mth wave potential related to the ith target azimuth angle; and combining the weight vectors of all the M wave potentials related to the ith target azimuth angle to obtain the weight vector matrix Wi of the ith target azimuth angle, wherein Wi=diag{Wi1, ...,Wim, ...,WiM}; (5) calculating the filtering output power of the ith target azimuth angle, comparing the filtering output power of all K target azimuth angles, and using the target azimuth angle corresponding to the maximum filtering output power as a final target azimuth angle.

Description

technical field [0001] The invention belongs to the technical field of radar, and specifically relates to a maximum likelihood target DOA estimation method based on multi-wave position joint processing, which is used to solve the problem of poor DOA estimation accuracy of airborne radar under low signal-to-noise ratio and low number of array elements. problem, and improve the DOA estimation accuracy of the target. Background technique [0002] The core task of airborne radar is to find and track targets in complex background environments, so it is very important to estimate the direction of arrival of target signals. The key to Direction Of Arrival (DOA) estimation technology is to use antenna arrays at different positions in space to receive signals from multiple signal sources in different directions, and use modern signal processing technology to estimate the direction of the signal source. The earliest DOA estimation algorithm is based on the Fourier transform linear sp...

AI Technical Summary

Problems solved by technology

[0004] For airborne radar, its received data includes target, clutter, interference and noise, so in order to accurately estimate the direction of arrival of the target, it is necessary to suppress the clutter and interference, that is, the estimation of the direction of arrival of the target and the space-time adaptive processing ( space-time adaptive processing, STAP), which makes the signal processing process very complicated

However, most of the DOA estimation algorithms are implemented in the background of a single wave position. The DOA estimation accuracy is affected by the array aperture and the signal-to-noise ratio, and the DOA estimation accuracy is poor under low signal-to-noise ratio and low number of array elements.

Images