一种抗信道多径的扫频-扩频调制技术  

An anti-multipath technique——Sweep-Spread Carrier modulation

作　　者：石维欣[1] 张歆[1] 

机构地区：[1]西北工业大学航海学院,西安710072

出　　处：《声学技术》2011年第4期369-372,共4页Technical Acoustics

摘　　要：水声信道是复杂的多径快衰落信道,其信道特性严重影响了水声通信的数据率和性能,抗多径干扰是提高水声通信系统性能的重要技术之一。对一种新的调制方法——扫频-扩频载波(Sweep-Spread Carrier,SSC)调制技术进行了深入研究,通过系统在水声信道实际数据的仿真,探究SSC的抗多径性能,简化了抗信道多径算法。SSC的基本思路是采用连续变化的载波频率,通过相关接收,将接收的多径信号在频域上分离,从而克服了码间干扰的影响。分析了在给定系统时不同信道多径时延对SSC性能的影响,以及给定信道时不同SSC参数对SSC性能的影响。仿真结果表明,选择合适的参数,SSC调制具有良好的抗多径性能。Underwater channel is a multipath,complex fading channel,which badly affects the data-rate and the per-formance of underwater acoustic communication.Anti-multipath is an important measure to improve the performance of underwater acoustic communication.A new modulation method – SSC（Sweep-Spread Carrier） is studied in this pa-per.Through the simulation with actual data of underwater acoustic channel,the anti-multipath performance of SSC is investigated and the anti-multipath algorithm simplified.The basic idea of SSC is that the continuously variable fre-quency of the carrier is used to change the time-delay caused by multipath channel into frequency interval,and so the multipath-signals are separated in frequency domain,which well overcomes the intersymbol interference（ISI）.The ef-fects of the different multipath channels and the different parameters of SSC for a given channel on the performances of SSC are analyzed.Simulation results confirm that the SSC modulation method has a good performance of an-ti-multipath for appropriately selected parameters.

关 键 词：抗多径技术 扫频-扩频载波调制 多径分离 水声通信 

分 类 号：TB556[理学—物理]