一种适用于快速双选衰落信道的时频双差分空时编码正交频分复用技术

Time-Frequency Double Differential Space-Time Coded OFDM Technique for Fast Doubly-Selective Fading Channel

为了保证在快速双选衰落信道下的有效数据传输,提出了一种新颖的时频双差分空时编码正交频分复用(OFDM)技术.该技术通过分别在OFDM系统的子载波之间和OFDM符号之间引入差分空时编码,实现了在系统时域和频域上的差分调制.文中同时给出了相应的准最优译码算法,并对系统性能进行了分析和计算机仿真.结果表明,该技术在快速双选衰落信道下能够保持良好的误码率性能.

Doppler shift gives rise to time-selectivity, while multipath propagation introduces frequency-selectivity in mobile links. In order to guarantee the effect data transmission in fast time-selective and frequency-selective （or doubly-selective） fading channel, a novel time-frequency double differential spacetime coded OFDM technique was proposed, in this technique, double differential space-time coding is introduced into both time domain and frequency domain in an OFDM system. A corresponding sub-optimal decoding algorithm was also derived. The performance analysis and computer simulation prove the robustness of the new system to fast doubly-selective fading.