基于MFT的2FSK信号解调的实现及其误差性能分析  

Implementation of 2FSK signal demodulation based on MFT and analysis on its error performance

作　　者：徐艺文[1] 陈忠辉[1] 魏宏安[1] 

机构地区：[1]福州大学物理与信息工程学院,福建福州350108

出　　处：《福州大学学报（自然科学版）》2011年第6期873-877,共5页Journal of Fuzhou University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60873186)

摘　　要：介绍基于瞬时傅立叶变换(MFT)的2FSK信号解调的基本原理,然后应用信号与系统的分析方法建立误差的变换域模型,并在此基础上分析旋转因子的误差对系统性能的影响.推导结果表明,在旋转因子近似值的模大于1的情况下积累误差会发散;反之,在模小于1的情况下则不发散,积累误差可被控制在一定范围.仿真结果验证了积累误差的这种变化趋势.因此,在实际应用中对旋转因子取近似值时应采用截尾法,而不宜采用四舍五入法,以保证积累误差不发散.The principal of the frequency shift keying（FSK） signal demodulation based on momentary Fourier transform（MFT） is presented.The analysis method of signal and system is used to form a transformation-domain model.Based on it,the effect on the system performance made by the inaccurate twiddle factor is analyzed.The inference results show that the accumulative error will disperse when the modulus of the twiddle factor used in application is greater than 1.And vise versa,when the modulus of the twiddle factor is less than 1,the error does not disperse and it can be controlled in certain extent.Finally,the simulation results verify the conclusion furthermore.Consequently,rather than rounding approach,it is better to use truncation approach in application.

关 键 词：瞬时傅立叶变换 频移键控 误差性能 数字化解调 

分 类 号：TN76[电子电信—电路与系统]