Method for positioning scatterer with known position under multipath propagation condition

Abstract

The invention discloses a method for positioning a scatterer with a known position under a multipath propagation condition, and aims to provide a positioning method which is rapid in positioning and relatively high in precision. The method is realized through the following technical scheme: the method comprises the following steps: in the environment of a direct path and an indirect path reflectedby the scatterer, allowing an observation station antenna array to receive the direct wave of a target radiation source signal and a reflected wave of the scatterer, transmitting an electromagnetic wave signal emitted by a target radiation source to the observation station, measuring an observation position coordinate and a scatterer position coordinate, and determining the distance between the scatterer and the observation station; under the condition that the target position is unknown; depending on an intercepted target signal, estimating the time difference between the direct wave and theindirect wave, the azimuth angle of the direct wave and the azimuth angle of the indirect wave; and calculating the distance between the scatterer and the observation station and the distance betweenthe target and the observation station, estimating the position of the target, determining the distance between the target radiation source and the observation station and a closed-form solution of the target position, obtaining a TDOA time delay difference value, and estimating the position coordinates of a node to be positioned.

Description

technical field [0001] The invention belongs to the technical field of electronic information, and in particular relates to a method of receiving target radiation source signal direct waves and scatterer reflection waves by using an observation station antenna array, and using the observation station antenna array to measure the azimuth angle of the target direct wave and the azimuth of the scatterer reflection waves The angle of arrival and the time difference of arrival TDOA between the direct wave of the target radiation source signal and the reflected wave of the scatterer are used to locate the target. Background technique [0002] The main way of radio wave propagation is space wave, that is, direct wave, reflected wave, refracted wave, diffracted wave and their synthetic waves. The multipath environment has a great influence on antennas with low ground clearance, and its path loss coefficient is greater than 2. When the antenna height increases, its path loss coeffici...

AI Technical Summary

Problems solved by technology

The geometric layout and the waveform and ambiguity functions of the source of opportunity are the key factors in the design of radar systems based on external radiation sources. The radar waveform and its ambiguity function properties determine the range resolution, range ambiguity interval, and range sidelobe of the radar. level and Doppler resolution and other system indicators, since the direct wave signal will be 80dB or even 100dB higher than the target echo power, the processing gain obtained only by using the antenna beam pointing and increasing the correlation time cannot meet the target detection index requirements. The time-frequency two-dimensional correlation peak of wave and reference signal is submerged by the sidelobe of strong direct arrival wave and multipath clutter signal, and the parameters of target echo cannot be extracted

Target tracking and identification only use a single external radiation source, and the positioning accuracy of a single station is not high. At present, the research on passive positioning technology mainly focuses on multi-station positioning technology, and in the existing research results of single-station positioning technology , there are few research results on NLOS error suppression

This is because in the single-station positioning technology, in order to obtain enough information required for positioning, the mobile observation station is often used. Although the mobile observation station can bring more information to the system during the mobile measurement process, the observation station The maneuvering of the NLOS will make the NLOS propagation environment more complicated and increase the difficulty of eliminating NLOS errors

However, NLOS error suppression is the key to improving positioning accuracy. Based on the above background, it will be more challenging and novel to overcome NLOS errors under the condition of limited information obtained by a single observation station.

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