A direction finding method and system based on digital interference system

Abstract

The invention provides a direction finding method based on a digital interference system, comprising: for an N-element uniform circular array antenna, converting a space electromagnetic wave into a digital voltage signal, and processing the voltage signal to obtain the voltage phase of each antenna; When the incident circular array antenna is 0°, the phase of each antenna is recorded as the test phase; the complex number corresponding to each antenna is constructed according to the voltage phase and the test phase; the theoretical phase of each antenna is calculated according to the initial phase of the elevation angle and azimuth; the introduction vector X and the direction vector G, combined with the constructed complex number to calculate the elevation angle and azimuth angle of the two-dimensional incident angle with the iteration number k+1. Compare, enter the output elevation angle and azimuth angle less than the threshold value; otherwise, add 1 to the value of k, and calculate the phase difference again. The advantage of the method lies in the use of complex number operations, which avoids the problem of phase ambiguity and operations such as logical judgment, and improves the direction finding accuracy.

Description

technical field [0001] The invention relates to the technical field of radio monitoring, in particular to a direction finding method and system based on a digital interference system. Background technique [0002] The interferometer direction finding system belongs to the phase direction finding system. When the incoming wave arrives at the direction finding antenna array, the different spatial positions of the different antennas lead to different phases of the signals received by each antenna unit to obtain the direction information of the incoming wave. Interferometer direction finding technology has been widely used in the field of passive direction finding because of its high precision, clear principle and wide frequency band. [0003] Due to its high direction finding accuracy, phase interferometer is a direction finding method commonly used in current direction finding systems. Because of the simple operation of the linear least squares method, the phase information o...

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Problems solved by technology

For the above-mentioned multi-baseline, parallel baseline, extended baseline, virtual baseline and other defuzzification methods, the higher the accuracy, the more the number of antennas, but only part of the antennas are used for angle measurement, and the rest of the antennas are only to exclude multi-values, which leads to a decrease in hardware resources. Underutilized to improve angle measurement accuracy with additional antennas

[0007] In short, the above method has steps such as search, clustering threshold setting, logical judgment, etc., and there are problems such as complex calculation and insufficient antenna application, resulting in low accuracy.

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