电讯技术
電訊技術
전신기술
TELECOMMUNICATIONS ENGINEERING
2015年
7期
773-778
,共6页
调频信号检测%参数估计%短时傅里叶变换%短时分数阶傅里叶变换%时频分析
調頻信號檢測%參數估計%短時傅裏葉變換%短時分數階傅裏葉變換%時頻分析
조빈신호검측%삼수고계%단시부리협변환%단시분수계부리협변환%시빈분석
frequency modulation signal detection%parameter estimation%short-time Fourier transform%short-time fractional Fourier transform%time-frequency analysis
调频信号的检测和参数估计一直是信号处理领域的研究热点之一。为深入挖掘短时分数阶傅里叶变换对调频信号的时频分析优势，从短时分数阶傅里叶变换的定义出发，推导了其时频分辨能力与信号参数的关系，并与短时傅里叶变换进行了对比分析。结论表明，短时傅里叶变换时频分辨能力与信号频率变化率有关，而短时分数阶傅里叶变换几乎不受调频率变化率影响。最后，通过对比仿真实验证明，对于频率变化率较小的信号，两者时频分辨效果差别不明显，对于频率变化率较大的信号，短时分数阶傅里叶变换的时频分辨效果更好。
調頻信號的檢測和參數估計一直是信號處理領域的研究熱點之一。為深入挖掘短時分數階傅裏葉變換對調頻信號的時頻分析優勢，從短時分數階傅裏葉變換的定義齣髮，推導瞭其時頻分辨能力與信號參數的關繫，併與短時傅裏葉變換進行瞭對比分析。結論錶明，短時傅裏葉變換時頻分辨能力與信號頻率變化率有關，而短時分數階傅裏葉變換幾乎不受調頻率變化率影響。最後，通過對比倣真實驗證明，對于頻率變化率較小的信號，兩者時頻分辨效果差彆不明顯，對于頻率變化率較大的信號，短時分數階傅裏葉變換的時頻分辨效果更好。
조빈신호적검측화삼수고계일직시신호처리영역적연구열점지일。위심입알굴단시분수계부리협변환대조빈신호적시빈분석우세，종단시분수계부리협변환적정의출발，추도료기시빈분변능력여신호삼수적관계，병여단시부리협변환진행료대비분석。결론표명，단시부리협변환시빈분변능력여신호빈솔변화솔유관，이단시분수계부리협변환궤호불수조빈솔변화솔영향。최후，통과대비방진실험증명，대우빈솔변화솔교소적신호，량자시빈분변효과차별불명현，대우빈솔변화솔교대적신호，단시분수계부리협변환적시빈분변효과경호。
Detection and parameter estimation of frequency modulation( FM) signal is always one of the re-search focuses in the field of signal processing. In order to find out the advantage of short-time fractional Fourier transform( STFRFT) in processing the FM signals,this paper analyzes the relationship between the time-frequency resolving ability and the parameter of the measured signals through STFRFT's definition, and compares with short-time Fourier transform( STFT) . As a conclusion,the time-frequency resolving a-bility of STFT is related to the signal's frequency fluctuation rate,however,the time-frequency resolving a-bility of STFRFT has nearly no relationship with the signal's frequency fluctuation rate. The simulation verifies that for the signals with low frequency fluctuation rate,STFT and STFRFT almost have the same time-frequency resolution,but for the signals with high frequency fluctuation rate,STFRFT has the better time-frequency resolution.
