该文提出了一种基于联合迭代解调译码的短波跳频OFDM系统,并在其接收端采用非相干序列检测和迭代译码相结合的联合迭代解调译码算法。该联合迭代解调译码算法可以降低差分检测时所导致的性能损失,同时,也可以提高短波FH/OFDM系统的可靠性。仿真结果表明:该方法可使其系统在短波信道中获得较好的比特误码性能,当Eb/N0=5.5dB时,其系统的比特误码率可达到10-5,数据传输速率达到8.912kb/s,显然,该联合迭代译码解调算法是适合短波FH/OFDM系统的。
A short-wave FH/OFDM system based on joint iterative demodulation and decoding is proposed. By combining the advantage of NSD technique and iterative demodulation and decoding, the method could compensate the SNR loss caused by differential detection and improve the reliability of short-wave communication system. Numeric simulation results show that the proposed method could effectively improve the system BER performance, while it reachs to 10-5 when SNR is 5.5 dB and data rate reachs to 8.192 kbps. Joint iterative demodulation and decoding is a practical algorithm for FH/OFDM systems.