Study on methods for suppression of Ionospheric Amplitude Contamination on OTHR

Since the absorption and polarization caused by anisotropy, dispersion and time varying of the ionosphere, amplitude and phase contaminations exist in the echo signal of a sky-wave radar. The cause and distribution of the amplitude contamination is given in this paper. Furthermore, the effects of amplitude contamination on the echo of sky-wave radar are analyzed from time domain and space domain. Through simulation, the results show that amplitude contamination can cause main-lobe spread and side-lobe raising. Based on the above analysis, this paper puts forward an algorithm of restraining amplitude contamination. Simulation test demonstrates that the proposed algorithm is efficient.