压缩频谱的差分跳频信号在莱斯衰落信道下的性能分析

Performance of a Compressed Spectrum Differential Frequency Hopping Signal over Rician Fading Channel

差分跳频(DFH)信号具有良好的抗多径衰落、抗干扰及高速数据传输能力,在短波和水声军事通信领域得到广泛应用。但是,在有限的传输带宽内差分跳频信号编码增益受限,特别是每跳携带多个比特时,该文提出一种压缩频谱DFH(CS-DFH)方法,可以在相同的比特每跳(BPH)和带宽下提高DFH信号的编码增益。对CS-DFH信号在莱斯(Rice)衰落信道下的误比特率(BER)理论上界进行了推导,并通过仿真验证。结果表明,莱斯信道中,在相同BPH、带宽条件下,与常规DFH相比,CS-DFH是一种可以获得更高BER增益的方法,特别是当莱斯因子K很小的时候。

Differential Frequency Hopping（DFH） signal can be used in the High Frequency（HF） and underwater acoustic communications because it has good resistance to multipath fading and jamming, at the same time with a high-speed data transmission capacity. However, taking into account the coding gain is limited within a finite transmission bandwidth, especially multiple Bit Per Hop（BPH）, a Compressed Spectrum DFH（CS-DFH） method is proposed to increase the coding gain of DFH signal for the same BPH and bandwidth. This paper develops an upper bound on the Bit Error Rate（BER） of CS-DFH signal in Rician channel, and its tightness is proved by simulations. For the same BPH and bandwidth, the results indicate that the CS-DFH is an efficient mean for obtaining higher coding gain than the existing DFH over the Rician channel, especially when the Rician factor K is small.