卫星通信中连续相位QPSK调制的带宽效率分析

连续相位调制(CPM)是一种带宽效率很高的调制技术,适用于卫星非线性信道。在将正交相移键控(QPSK)表示成CPM的基础上,提出了一种基于离散傅里叶变换(DFT)的谱密度计算公式。利用MATLAB的快速傅里叶变换(FFT)运算仿真了连续相位QPSK(CPQPSK)的功率谱,结果表明CPQPSK较QPSK具有更高的带宽效率。

Bandwidth Efficiency Analysis of Continuous Phase QPSK Modulation in Satellite Communication

Continuous phase modulation（CPM） is a modulation technology with high bandwidth ef- ficiency,and is suitable for nonlinear channel of satellite. Based on representing quarternary phase shift keying （QPSK） as CPM,this paper presents a power spectrum density （PSD） calculating for- mula based on discrete Fourier transform （DFT）,which uses fast Fourier transform （FFT） based on MATLAB to simulate the power spectrum of continuous phase QPSK （CPQPSK）, and results show that CPQPSK signal has higher bandwidth efficiency than QPSK signal.