Method for inhibiting ionospheric clutter in portable high frequency groundwave radar

Abstract

The invention relates to the radar anti-interference technical field, in particular to a method for inhibiting ionospheric clutter in portable high frequency groundwave radar. In the invention, a plurality of sets of auxiliary crossed loops are arranged in the vertical direction of original crossed loop antennas of the portable high frequency groundwave radar, adaptive cancellation is carried out on the received signals of auxiliary crossed loop antennas, a main crossed loop and monopole antennas; the received signals of the main crossed loop and the monopole antenna are used as a basic input signal, the difference of the received signals between each auxiliary crossed loop antenna and the main crossed loop antenna are used as a reference signal to input three mutually independent self-adapting filters; an error signal is output from the self-adapting filters to be echoed signals of the main crossed loop and the monopole for inhibiting ionospheric clutter. The invention has the following advantages: an ideal ionospheric clutter reference signal can be obtained and the working efficiency and detection performance of radars can be greatly increased.

Description

technical field [0001] The invention relates to the technical field of radar anti-jamming, in particular to a method for suppressing ionospheric clutter in a portable high-frequency ground wave radar. Background technique [0002] Due to its unique over-the-horizon and all-weather detection capabilities, high-frequency ground wave radar has been widely studied and successfully applied to the measurement of ocean surface dynamic parameters, and can detect moving targets such as ships and aircraft in real time. However, there are still great challenges in the application of medium and long-range high-frequency ground wave radar. The high-frequency ground wave radar emits vertically polarized electromagnetic waves to the sea surface along the horizontal direction, but in practice, an ideal null trap cannot be formed in the direction of the antenna zenith, so some of the energy will be emitted to the sky and reflected by the ionosphere, thereby forming an ionosphere clutter. ...

AI Technical Summary

Problems solved by technology

[0004] In the current existing high-frequency radar anti-jamming methods, adaptive beamforming ionospheric suppression methods, polarization filtering methods, and filtering methods in the time domain and frequency domain or their combined domains are usually used, in which the adaptive beamforming ionosphere The suppression method needs to configure a two-dimensional array on the horizontal plane (Gao Huotao, Qin Chenqing, Yang Zijie: High-frequency ground wave radar anti-jamming method based on antenna subarray, CN100380135C), while the polarization filtering method needs to set up a large horizontal antenna (H Leong: 'Adaptive nulling of skywave interference using horizontal dipole antennas in coastal surface HF wave radar system', Radar 97, 14-16 October 1997, Publication No.49: 26-30), both methods are relatively complicated to implement, The method of filtering in the time domain and frequency domain or their joint domain (Xiong Xinnong, Wan Xianrong, Ke Hengyu, Xiao Huaiguo, Ionospheric Clutter Suppression of High Frequency Ground Wave Radar Based on Time-Frequency Analysis, System Engineering and Electronic Technology, 2008, p. 8) can not completely eliminate the influence of clutter on the useful signal, there are residual clutter and a certain signal loss

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