基于状态网格图的差分跳频G函数构造方法研究

摘要

By using frequency trellis diagram method to construct G function in DFH system, when bit number per hop increase or the number of available frequency choices decrease, SER will be degraded since the minimum free distance of frequency trellis diagram decrease. This paper proposes a G function constructing method based on status trellis diagram and corresponding encoding model. Theoretical analysis and simulation results show that the proposed methods solve the above problems effectively by keeping the length of code shift register and selecting the optimal tap structure.%采用频率网格图的方法构造差分跳频G函数,在增加每跳携带的信息比特数或减小可用跳频点数时,由于频率网格图的最小自由距下降,误码率性能会大幅下降.因此提出一种基于状态网格图的G函数构造方法,给出了基于多进制卷积编码结合高阶MFSK调制的通用编码模型.理论分析和仿真结果表明,该方法通过保持编码器约束长度不变和选取最优的抽头结构,有效地解决了上述问题.