基于时频图峰均比曲线的FSK码速率估计  

FSK Symbol Rate Estimation Based on Peak-to-average Ratio Curve of Time-Frequency Diagram

作　　者：岳新宇 施昉[1,2] 张润生 YUE Xin-yu SHI Fang ZHANG Run-sheng(Equipment Engineering Technology Research Laboratory,Shijiazhuang 050081 ,China The 54th Research Institute of CETC,Shijiazhuang 050081 ,China)

机构地区：[1]装备工程技术研究实验室,河北石家庄050081 [2]中国电子科技集团公司第五十四研究所,河北石家庄050081

出　　处：《舰船电子对抗》2017年第4期42-45,120,共5页Shipboard Electronic Countermeasure

摘　　要：数字通信信号的码速率是其重要属性,估计信号的码速率是无线电频谱监测中的关键问题。针对现有FSK信号码速率估计抗噪性能不高的问题,提出基于时频图峰均比曲线的移频键控(FSK)码速率估计算法,该算法通过短时傅里叶变换获取FSK信号的时频图,而后通过提取时频图的峰均比曲线获得FSK信号的频率变化序列,最后通过傅里叶变换对峰均比曲线进行频率估计,得到FSK信号的符号速率估计值。仿真结果表明该算法相比基于瞬时频率的FSK估计算法有更好的抗噪性能,具有3~4dB的信噪比增益。Symbol rate is an important attribute for digital communication signal, and the estimation of signal symbol rate is the key problem in the radio spectrum monitoring. Aiming at the problem that the anti-noise performance of symbol rate estimation for existing frequency shift keying （FSK） signal isn＇t perfect,this paper puts forward the estimation algorithm of FSK symbol rate based on peak-to-average ratio curve of time-frequency diagram. The algorithm obtains the time-frequency diagram of FSK signal by means of short time Fourier transformation （STFT） ,then gains the fre- quency change sequence of FSK signal by extracting peak-to-average ratio curve of time-frequency diagram,finally performs the frequency estimation to get the symbol rate estimation value of FSK signal through Fourier transformation. Simulation results show that the proposed algorithm has better anti-noise performance than FSK estimation algorithm based on instantaneous frequency, and has the signal-noise ratio gain of 3~4 dB.

关 键 词：时频图 移频键控 峰均比 码速率 

分 类 号：TN929.5[电子电信—通信与信息系统]