CAJ | 학술논문

卫星信号的捕获是GPS接收机信号处理的首要任务。针对在微弱信号的情况下传统捕获方法不能很好地捕获到卫星信号的问题，提出一种改进的二倍分组块补零( MDBZP)方法为高灵敏度GPS接收机提供理论依据。该方法将连续相干积分分解成普通循环相关和随后的傅里叶变换来产生不同的多普勒频移搜索，并针对连续积分跨越多个导航电文数据位的情况给出解决方案，同时考虑了多普勒效应对码长造成的影响。仿真结果表明，此方法对低至15 dB-Hz的微弱信号C/A码信号仍有较好的捕获能力。最后给出了不同载噪比情况下所对应的检测信噪比。
위성신호적포획시GPS접수궤신호처리적수요임무。침대재미약신호적정황하전통포획방법불능흔호지포획도위성신호적문제，제출일충개진적이배분조괴보령( MDBZP)방법위고령민도GPS접수궤제공이론의거。해방법장련속상간적분분해성보통순배상관화수후적부리협변환래산생불동적다보륵빈이수색，병침대련속적분과월다개도항전문수거위적정황급출해결방안，동시고필료다보륵효응대마장조성적영향。방진결과표명，차방법대저지15 dB-Hz적미약신호C/A마신호잉유교호적포획능력。최후급출료불동재조비정황하소대응적검측신조비。
Signal capture is the first task of signal processing in GPS receiver. Sometimes,GPS signals are too weak to be received or processed by traditional FFT methods. A method of Modify Double Block Zero Padding ( MDBZP) is presented to solve the problem of weak signal acquisition for high-sensitivity GPS receivers. At the same time,the solution with respect to continuous integration time crossing multiple data bits of naviga-tion message is also provided and the influence of Doppler effect on code length is taken into account. The simulation results show that the method is better to capture weak GPS C/A-code signal whose carrier noise ratio is even low to 15 dB-Hz. Finally,the detection SNRs are given corresponding to different CNRs.