CAJ | 학술논문

快速衰落信道(FFD)是浅海中常见的畸变信道模型之一,通常用信道相干时间来描述其多普勒扩展程度.分段副本相关器(SRC)是FFD信道的最佳似然比检测器,但当信道相干时间未知时,其性能因失配受到较大影响.针对此种情况,提出了多重假设SRC,该方法能简单有效地估计FFD信道相干时间并解决SRC的失配问题.
쾌속쇠락신도(FFD)시천해중상견적기변신도모형지일,통상용신도상간시간래묘술기다보륵확전정도.분단부본상관기(SRC)시FFD신도적최가사연비검측기,단당신도상간시간미지시,기성능인실배수도교대영향.침대차충정황,제출료다중가설SRC,해방법능간단유효지고계FFD신도상간시간병해결SRC적실배문제.
In shallow water sonar environment,one typical type of channel distortion is the fast fading distortion(FFD),which is usually characterized by its coherence time.Under the FFD model,an echo from a target will encounter doppler spread,and the likelihood ratio test yields the segmented replica correlator(SRC)detector.However,when the coherence time is unknown,the SRC will not fully exploit its advantage because of mismatching.For this reason,a multihypothesis SRC is proposed.This multihypothesis testing could estimate the coherence time of the fast fading distortion channel,and improve the performance of the mismatched SRC.Simulation results show that the proposed multihypothesis SRC is simple,convenient,and feasible.