两种键控方式在短波数字通信中的性能比较

Performance Comparison of Two Keying Methods in Short Wave Digital Communications

针对短波数字通信采用的差分相移键控（DPSK）和非相干移频键控（NFSK）两种调制技术的性能进行分析和比较。以采用自动请求重发（ARQ）技术的数字窄带直接印字电报（NBDP）为例,分别对两种调制技术下的传输信息恒比码码组回传概率和剩余错组率进行了分析;并对系统性能参数进行了理论和数值分析。在信噪比同样的条件下,得出了使用DPSK技术的短波通信系统能有效地提高通信质量和降低ARQ的重传概率和剩余错组率的结论,为更好地利用短波通信系统进行数字通信提供理论依据。

The performances of differential phase shift keying （ DPSK ） and non-coherent frequency shift keying（ NFSK） used in shortwave digital communications are analyzed and compared. The packet retransmission probability and residual block error rate of NBDP, which uses ARQ with the two keying methods are analyzed respectively. The system performance parameters are analyzed theoretically and numerically. The conclusion is drawn that for given signal-to-noise ratio （SNR） , the short-wave communication（SWC） ARQ systems employing DPSK achieve higher merit with lower packet retransmission probability and residual block error rate. The study can be a theoretical guid- ance on practical applications of SWC systems.