同步短波差分跳频多址系统单用户及多用户检测的性能

Single-User and Multi-User Detection Performance of Synchronous Shortwave Differential Frequency Hopping Multiple-Access Systems

该文讨论同步短波差分跳频在多址通信中的单用户与多用户检测的性能。给出了单用户检测在无背景噪声及有背景噪声的情况下,系统的比特误码率(BER)上界,并对其进行了数值仿真。其结果表明:在无背景噪声的情况下,当总用户数为2时,系统的BER可达10-6;若系统可以得到精确的干扰状态信息(JSI),则多址性能可以得到极大的提升。在此基础上,提出了一种迭代多用户检测算法,在迭代过程中估计各可用频率上的JSI,并利用它对多个用户进行极大似然检测,其仿真结果表明了多用户检测相对于单用户检测,其性能获得了明显的改善。

In this paper, theoretical analysis and simulations are performed on the performance of synchronous shortwave Differential Frequency Hopping （DFH） systems in the Multiple-Access （MA） communications. Single-user detection and multi-user detection are both considered. For single-user detection, Bit Error Rate （BER） upperbounds are derived and verified via simulation, both in the noiseless case and noise case. Results show that when the number of users is 2, the BER is 10^-6 for the noiseless case. Furthermore, MA performance can be significantly improved if exact Jammer State Information （JSI） is available. Therefore, an iterative multi-user detection algorithm is proposed. In the iteration process, JSI of each available frequency is estimated and used to perform maximum likelihood detection for each user. Simulation results show that significant performance improvement is obtained relative to single-user detection.