卷积码差分跳频系统抗部分频带干扰的性能

基于对无编码差分跳频系统抗部分频带干扰性能的研究,将卷积码引入差分跳频系统,研究了在有精确干扰状态信息的情况下,采用无迭代译码和迭代译码时相对于无编码系统的性能改善.同时,在无法得到精确干扰状态信息的情况下,提出了一种迭代干扰状态估计及译码算法.理论分析结果表明:在有精确干扰状态信息的情况下,采用卷积纠错编码和无迭代译码,对可用频率数为8的差分跳频系统,当比特误码率(BER)为10~(-6)时,性能改善约为2.5dB;而采用迭代译码,当BER为10~(-10)时,相对于无迭代译码,性能可进一步改善6dB.仿真结果则验证了迭代估计及译码算法的正确性,采用该算法可使编码系统在无精确干扰状态信息的情况下,仍能保持良好的抗干扰能力.

Performance of convolutionally coded differential frequency hopping systems in partial-band jamming

Based upon the research on the performance of uncoded differential frequency hopping(DFH)systems against partial-band jamming,convolutional codes were introduced to the DFH systems and their performance improvements were investigated with non-iterative decoding and iterative decoding respectively,on condition that exact jalnnler state information(JSI) was available.If exact JSI was not available,however,an iteratively joint jammer state estimation and decoding algorithm was proposed.Theoretical analysis shows that if exact JSI is available,for a DFH system with 8 fre-quencies,the performance improvement is approximately 2.5dB at the BER of 10~(-6) when using convolutional codes and non-iterafive decoding.The performance can be further improved by 6dB at the BER of 10~(-10) compared with non-iterative decoding,when iterative decoding is used.Simulation results validate the proposed algorithm and show that the coded system maintains robust anti-jamming capability by using this algorithm even without exact JSI.