具有记忆性的对称升余弦键控调制方法

Memory-Based Symmetric Raised-Cosine Keying Modulation Method

对称升余弦键控(SRCK)可以使已调信号的相位和频率均具有连续性.针对SRCK信号的通信误码率比最小频移键控(MSK)信号偏高的问题,提出了一种改进的SRCK调制方法,通过在信号码元对应的已调信号之间加入记忆性来改善误码率性能.仿真结果表明:该方法可以在已调信号频域能量集中度优于MSK信号的前提下,获得误码率性能优于MSK信号3dB的增益;采用改进的SRCK信号进行通信时,可以通过计算其最小欧氏距离来选择适合相应通信系统的调制参数.

The phase and frequency of the symmetric raised-cosine keying （SRCK） modulation signals are continuous, but the bit error rate （BER） of the SRCK signals is higher than that of the minimum frequency shift keying （MSK） signals. In order to solve this problem, an improved SRCK modulation method is devised to decrease the BER by adding the memory between the SRCK signals corresponding to symbols. Simulated results show that the signals obtained through the devised modulation method are superior to the MSK signals in terms of the energy concentration and the BER performance, with a gain of 3 dB, and that, for the improved SRCK signals, suitable modulation parameters can be determined by calculating the minimum Euclidean distance.