CAJ | 학술논문

根据极大似然估计理论，通过载波频率和频率变化率分段对消、快速傅里叶变换( FFT)结果选大估计载波频率和频率变化率，实现载波信号捕获，建立了高动态全球定位系统( GPS )载波的线性调频( LFM)信号模型，并给出了算法的具体实现。详细分析了该算法中检测统计量的分布特性，推导了恒虚警准则下的检测门限，并讨论了其中关键参数的设计。仿真结果表明，该算法可以实现对18 dBHz的GPS高动态信号的载波捕获。
근거겁대사연고계이론，통과재파빈솔화빈솔변화솔분단대소、쾌속부리협변환( FFT)결과선대고계재파빈솔화빈솔변화솔，실현재파신호포획，건립료고동태전구정위계통( GPS )재파적선성조빈( LFM)신호모형，병급출료산법적구체실현。상세분석료해산법중검측통계량적분포특성，추도료항허경준칙하적검측문한，병토론료기중관건삼수적설계。방진결과표명，해산법가이실현대18 dBHz적GPS고동태신호적재파포획。
According to the maximum likelihood( ML) method,through the correlation cancellation of carri-er frequency and carrier frequency change selecting maximum value of fast Fourier transform( FFT) ,carrier acquisition is realized and a linear frequency modulation( LFM) signal model of high dynamic global posi-tioning system( GPS) carrier is established. The implementation solution of the algorithm is presented in which the distributing characteristic of detecting statistic quantity is analyzed,the detecting threshold under the constant false alarm rules is derived and the key parameters design is presented. The simulation results show that the algorithm can achieve the carrier acquisition of high dynamic GPS signals in 18 dBHz.