DAB传输中时间交织的改进

Improvement of DAB Time Interleaving

无线通信中多径信道除了频率选择性衰落之外 ,由于接收端的移动、环境的影响可以导致较长时间的严重衰落 (慢衰落 ) .为改善系统的抗慢衰落特性 ,基于对欧洲DAB(数字音频广播 )的时间交织方式的分析 ,提出了改进时间交织的新的数据安排方式 .系统模拟证实了新方式比原来的方式在系统抗慢衰落特性上有显著的改进 ,也证实了提高码元间相隔帧数的优化设计可以直接预期抗慢衰落的性能 .

Besides the frequency selective fading in multipath channel of wireless communication, there exists the slow fading varying from 20 ms up to 100 ms due to the receiver movement and environmental change. Based on the performance analysis of DAB(Digital Audio Broadcasting) time interleaving, an improved time interleaving method is presented. The simulation results show that by increasing the frame number between the two adjacent symbols, the system's ability to resist the slow fading could be directly estimated and then improved.