【摘要】：處于海洋工作環(huán)境下的雷達(dá)系統(tǒng)會受到海雜波和多徑效應(yīng)的影響,如何合理有效的從復(fù)雜的回波信號中將源信號提取出來,成為現(xiàn)代科學(xué)和軍事領(lǐng)域一個重要的課題。海雜波作為一種普遍存在的干擾源,對雷達(dá)的信號處理、目標(biāo)檢測等會產(chǎn)生很大的影響。建立一個準(zhǔn)確的海雜波統(tǒng)計分布模型,不僅能為雷達(dá)系統(tǒng)的檢測提供了理論依據(jù),而且能抑制雜波,對提高雷達(dá)的傳輸性能起到巨大的作用。當(dāng)接收到目標(biāo)的回波信號時,由于海面的散射和反射作用,會產(chǎn)生多徑效應(yīng),出現(xiàn)時延現(xiàn)象,導(dǎo)致信號的衰弱。本文針對線性調(diào)頻信號(LFM),建立了多徑散射模型,并進(jìn)行了仿真驗證。在此基礎(chǔ)上提出了兩種基于LFM的多徑分離算法,分別為基于高階累積量和基于分?jǐn)?shù)階傅里葉變換(FRFT)的方法,并進(jìn)行了對比分析。結(jié)果表明,基于高階累積量的分離算法相對比較簡單,易于實現(xiàn),在信號的實時處理領(lǐng)域會有很好的效果,但是由于其采樣數(shù)量大,收斂速度慢,導(dǎo)致穩(wěn)態(tài)誤差較大,效果不穩(wěn)定。而基于FRFT的算法相對而言能更有效地抑制雷達(dá)回波信號中的多徑分量對LFM信號接收的影響,從而達(dá)到更好的分離效果。
[Abstract]:Radar system in marine environment will be affected by sea clutter and multipath effect. How to extract the source signal from complex echo signal reasonably and effectively has become an important subject in modern science and military field. As a common jamming source, sea clutter has great influence on radar signal processing and target detection. Establishing an accurate statistical distribution model of sea clutter can not only provide a theoretical basis for radar system detection, but also suppress clutter, and play a great role in improving the transmission performance of radar. When the echo signal of the target is received, due to the scattering and reflection of the sea surface, the multipath effect will be produced, and the phenomenon of delay will occur, which will lead to the signal weakening. In this paper, a multipath scattering model for linear frequency modulated signal (LFM),) is established and verified by simulation. On this basis, two multipath separation algorithms based on LFM, which are based on higher order cumulants and fractional Fourier transform (FRFT), are proposed and compared. The results show that the separation algorithm based on high-order cumulants is relatively simple and easy to implement, and it will have good results in the field of real-time signal processing. However, due to the large number of samples and the slow convergence rate, the steady-state error is large. The effect is unstable. The algorithm based on FRFT can suppress the influence of multipath component of radar echo signal on the receiving of LFM signal more effectively and achieve better separation effect.
【學(xué)位授予單位】：長春理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TN957.51

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 王鋼;孫斌;;盲信號分離技術(shù)及算法研究[J];航天電子對抗;2015年04期

2 季策;王艷茹;王曉宇;;一種基于標(biāo)準(zhǔn)峭度的新型復(fù)數(shù)盲分離算法[J];東北大學(xué)學(xué)報(自然科學(xué)版);2015年05期

3 王利;劉超;范麗紅;張明;;一種GPS接收機抑徑性能檢測新方法[J];工程勘察;2015年02期

4 何友;黃勇;關(guān)鍵;陳小龍;;海雜波中的雷達(dá)目標(biāo)檢測技術(shù)綜述[J];現(xiàn)代雷達(dá);2014年12期

5 李W，

本文編號：2209207