Method for allowing ground wave over-the-horizon radar to achieve multifrequency transmission and reception simultaneously

Abstract

The invention relates to a method for allowing a ground wave over-the-horizon radar to achieve multifrequency transmission and reception simultaneously. Expansion of the ground wave over-the-horizon radar from a single-frequency mode to a multifrequency mode is achieved based on an interframe phase linear offset method. At a transmission end, proper phase offset is set according to a sweep frequency period and frequency ways, a frequency synthesis circuit generates a plurality of transmission signals with different frequencies and interframe phase change rates, and the plurality of transmission signals are transmitted through antennas. At a receiver end, a frequency mixing circuit transduces a plurality of reception signals with different frequencies onto the same frequency, echo signals with multiple frequencies are separated on a Doppler after being subjected to twice fast Fourier transform, and therefore, working in multiple frequencies can be achieved. By means of the method, the ground wave over-the-horizon radar can work in multiple frequencies simultaneously, hardware cost is not added, mutual interference caused by working in multiple frequencies simultaneously is avoided, data obtained in different frequencies can be separated easily, and detection performance and detection accuracy of the radar are improved.

Description

technical field [0001] The invention belongs to the technical fields of radar, radio physics, etc., and particularly relates to a method for realizing simultaneous multi-frequency transmission / reception of ground-wave over-the-horizon radar. Background technique [0002] As a new type of marine remote sensing equipment, ground wave over-the-horizon radar equipment can conduct all-weather, over-the-horizon, large-area real-time monitoring of the ocean surface environment and maritime moving targets. At present, most high-frequency ground wave radars at home and abroad have adopted the chirp interrupted continuous wave (FMICW) system, which introduces transceiver modulation technology on the basis of chirp frequency modulated continuous wave (FMCW), which can better solve the reception problem caused by the strong direct wave signal. Machine blocking problem. [0003] Most of the traditional over-the-horizon radars work on a single frequency point, the anti-interference abili...

AI Technical Summary

Problems solved by technology

However, under the multi-frequency system, the FMICW parameter design will be greatly restricted, and the parameters of each frequency are mutually restricted, especially the distance aliasing problem of each frequency is difficult to overcome. decline

Images