中文摘要：

为了改善连续相位调制（CPM）信号的性能，提出了多分支分数多比特差分检测技术．通过将不同分数比特区间差分信号合并判决，使不同相位状态之间的距离增大，改善了信噪比．从物理意义上对该算法的实质进行解释，并对达到最大性能增益的分数比特区间上限进行了理论分析．仿真分析结果表明：与传统的1比特、2比特差分检测相比，多分支分数多比特差分检测技术增加了不同相位状态之间的距离，从而获得误码率性能的改善；当分数比特区间为使得该区间差分信号与判决码元同极性的最大区间时，可以获得最大的性能增益．

英文摘要：

The multi-branch fractional multi-bit differential detection technique for improving the performance of continuous phase modulation signals is proposed. The distance between different phase states is increased by combination and decision of different multi-bit differential signals. The essence of the technique is physically explained, and a theoretical analysis of the upper bound of the fractional bit duration for maximum performance improvement is conducted. Simulation results and further analysis show that the multi-branch fractional multi-bit differential detection technique increases the distance between phase states compared with 1-bit differential detection and 2-bit differential detection, which leads to the performance improvement; when the fractional bit duration is the maximal duration in which the polarity of the differential signal is the same as the decision symbol, the maximum performance gain can be obtained.