一种CPFSK信号调制指数估计方法

An algorithm of CPFSK modulation index estimation

随着通信技术与通信方式的快速发展,通信信号调制方式与通信系统越来越复杂。复杂通信信号连续相位频移键控(CPFSK)由于其频谱利用率高,大量用于卫星通信等领域。针对复杂信号CPFSK的参数估计问题,提出一种基于李雅普诺夫指数的CPFSK信号调制指数估计方法。通过CPFSK信号李雅普诺夫指数与调制指数的数学关系模型,提取李雅普诺夫指数估计信号调制指数。仿真验证了算法性能,得到CPFSK调制指数估计均方根误差随信噪比的变化曲线。此方法计算复杂度低且实现简单,适用于CPFSK信号与常规频移键控(FSK)信号的调制指数估计。

With rapid development of communication technology and the way of communication, the modulation type of communication signal and communication system become more and more complex. Due to the high spectrum utilization rate, Continuous-Phase Frequency Shift Keying（CPFSK） is widely used in satellite communication. Considering parameters estimation of CPFSK, an algorithm of CPFSK modulation index estimation is studied based on Lyapunov exponent. With the mathematical relationship between Lyapunov exponent and modulation index, modulation index is estimated by extracting Lyapunov exponent, and the performance is simulated by modulation index Root Mean Square Error（RMSE） vs. Signal-to-Noise Ratio（SNR） curves. With low complexity, this algorithm can be applied to CPFSK and common Frequency Shift Keying（FSK） signal.