在天波雷達(dá)中電離層的運(yùn)動(dòng)會帶來回波信號在頻率的調(diào)制，從而造成雷達(dá)海雜波的展寬；在對回波做相關(guān)積累前，對調(diào)制的補(bǔ)償是非常重要的。該文給出了一種新的基于修正的自適應(yīng)短時(shí)傅立葉變換的補(bǔ)償方法，通過對沒有電離層擾動(dòng)的高頻表面波雷達(dá)數(shù)據(jù)人為地添加行進(jìn)電離層擾動(dòng)(TID)得到實(shí)驗(yàn)數(shù)據(jù)。測試結(jié)果表明，該方法能有效地補(bǔ)償快速的TID污染，并且對不同電離層頻率調(diào)制具有良好的自適應(yīng)性。
關(guān) 鍵 詞 頻率調(diào)制; 電離層; 短時(shí)傅里葉變換; 天波雷達(dá)

Abstract The ionospheric layer movement produces frequency modulation for the HF sky-wave radar signal such that the sea clutter is broadened in Doppler domain. Compensation for the modulation is significant before radar coherent integration. This paper addresses a modified adaptive short time Fourier transform (MASTFT) and proposes a MASTFT-based compensation method. Experimental tests are constructed by inducing the contamination of simulative traveling ionospheric disturbance (TID) to the undisturbed data collected by high frequency surface wave radar (HFSWR). The test results show that the proposed method can effectively compensate even for rapid TID and has good adaptability for different ionospheric frequency modulations.
Key words frequency modulation; ionosphere; short time Fourier transform; sky wave radar