Rate-embedded differential space-time codes

Differential space-time codes (DSTC) can be used to implement high reliable transmission in cases where the channel fading coefficients change too rapidly to be estimated and the channel state information (CSI) is unknown at receiver. But in most of the existing differential space-time schemes, a great many of redundant symbols have always been introduced so that high rate transmission cannot be implemented. In order to overcome such a shortcoming, we embedded some high rate space-time codes, such as full diversity full rate (FDFR) codes into the time intervals of the conventional differential space-time coding schemes and proposed a new class of rate-embedded differential space-time codes. Simulation results verify that the proposed differential space-time codes can improve the total transmission rate greatly; meanwhile, high error performance also can be maintained Compared with the conventional differential space-time schemes, the proposed differential space-time codes can achieve much better bit error performance for both quasi-static channels and time-selective fading channels.