水声多径信道中的标识延迟空时扩展发射分集

水声信道存在严重的传播时延和多径时延，该文提出了一种带有信道标识的延迟空时扩展(LDSTS)发射分集方案，通过信道探测、延时发射和Rake接收来消除传播时延和多径时延的影响，且顺序延时发射保证了方案的实用性。文中给出了采用频移键控和相移键控调制的LDSTS方案的信号模型、误码率分析和比特误码率的仿真。仿真表明，在多径水声信道中，LDSTS可以更好地实现完全发射分集。

A Transmitter Diversity Scheme Based on Labelled Delay Space Time Spreading in Underwater Acoustic Communication Systems

A transmit diversity scheme, called Labelled Delay Space-Time Spreading (LDSTS) is proposed for communication systems in underwater acoustic(UWA) channels with propagation delays and multipath spreading. The scheme eliminates the propagation delays and multipath delays by using the channel probe signals, transmitted in sequence and Rake receivers. The signals are transmitted from transducers in sequence enable the scheme is practice for applications to UWA communication system. The signal models are proposed and BER performances of the scheme with FSK and PSK modulation are analyzed. Simulations results show that the scheme realizes complement transmit diversity gains in multipath UWA channel.