认知异步跳频通信系统同步方案研究

提出了一种认知异步跳频通信系统同步方案.通过采用两套可选的跳频图案,在当前发射跳期间,认知下一跳两个频点的状况,自适应选择下一跳频点进行信息传输,进一步提高了异步跳频通信系统的抗干扰能力,仿真结果表明,在同步概率大于95%时,新方案将用户容量提高了5倍多;通过引入循环前缀,实现了接收机跳频图案的自适应识别,并解决了跳频信号位同步信患不易提取的难题;最后还给出了异步跳频通信系统和认知异步跳频通信系统的同步性能分析.

Research on the synchronization scheme of a cognitive asynchronous frequency-hopping communication system

A synchronization scheme for a cognitive asynchronous frequency-hopping communication system(CAFHCS) is proposed. There are two optional frequency-hopping patterns in this scheme. In transmiting information in the current hop, the status of the two frequency points which are calculated by the two patterns for the next hop are sensed simultaneously. The transmitter selects the frequency point for the next hop adaptively according to the sensing results, which improves the anti-jamming performance of the asynchronous frequency-hopping communication system(AFHCS). It is observed from simulation results that the users' capacity of the CAFHCS increases over 6 times compared with that of the AFHCS when the probability of synchronization is above 95％. By introducing the cyclic prefix to a hop signal, the frequency-hopping pattern recognition is implemented adaptively at the receiver, and the difficult problem of bit synchronization of the frequency-hopping signal is solved as well. Furthermore, the performance analysis of the synchronization scheme for AFHCS and CAFHCS are given.