Research On Shortwave DOA Estimation Under The Disturbances Of UHV Transmission Lines

Energy is an important guarantee for economic development.China's power and energy resources distribution and productivity development has obvious regional characteristics,the transmission distance of ordinary power grid is only about 500 km,can not meet the transmission requirements;this situation,the development of special high-voltage transmission into China's power industry development inevitable choice.The research on the short-wave spatial spectrum estimation and direction finding algorithm of UHV transmission line can shorten the protection distance of the higher voltage transmission line to the radio direction-finding station,and effectively solve the problem of the transmission line to the radio direction of the problem of electromagnetic interference,the two of the harmonious construction and operation of great significance.In this paper,the spatial spectrum estimation and direction finding algorithm of weak signal under passive interference of UHV transmission line is studied.In the study of passive interference of shortwave radio communication in power lines,ZP30101 vertical tower,which is used in UHV transmission line of Xiangjiaba-Shanghai line,is selected to simulate the electromagnetic scattering under plane wave incident,Passive Disturbance of Tower.Based on the spatial spectrum estimation model and the classical MUSIC algorithm,the mean signal-to-noise ratio threshold is defined as a measure of the performance of the MUSIC algorithm for resolving weak signals.The MUSIC algorithm The reason of the resolution degradation under passive jamming is analyzed in detail,and three representative direction finding algorithms for weak signals such as noise subspace invariance algorithm,jamming algorithm and extended Noise subspace algorithm,and the performance of the three algorithms are analyzed in detail.The passive interference of the UHV transmission lines to neighboring radio stations often has different power in different directions.Based on the improvement of separation noise spreading subspace,noise subspace invariance and Capon beam forming spatial filtering,three new anti-jamming spatial spectrum estimation algorithms,namely improved extended noise subspace algorithm,improved noise subspace invariance algorithm and Capon-MUSIC algorithm,can be seen by comparing spatial spectrum and performance simulation.Three improved algorithms and can accurately estimate the direction of arrival of the weak signaland perform well.To eliminate the interference of the UHV transmission line to the adjacent goniometer(station)and to estimate accurately the useful signal azimuth angle,and shorten the feasibility of the distance between the two provides a theoretical basis.