CAJ | 학술논문

互相关干扰由C／A码相关特性造成，是GPS系统不可避免的问题，已成为制约接收机灵敏度的因素之一。文中提出了一种新的互相关干扰下自相关检测方法———多组数据比较法（M ulti‐groups data comparison ，MDC）。该方法比较多组数据下捕获结果的多普勒频率和码相位，确定自相关峰的多普勒频率与码相位。对比基于均方比（Mean square ratio ，MSR）和峰值相差（Peak difference ，PD）检测两种方法，该方法在互相关干扰下有效提高弱信号发现概率。仿真结果表明，强信号为－124 dBm时，该方法对－145 dBm弱信号的检测概率为83％。该方法对GPS接收机弱信号捕获研究有实际意义。
호상관간우유C／A마상관특성조성，시GPS계통불가피면적문제，이성위제약접수궤령민도적인소지일。문중제출료일충신적호상관간우하자상관검측방법———다조수거비교법（M ulti‐groups data comparison ，MDC）。해방법비교다조수거하포획결과적다보륵빈솔화마상위，학정자상관봉적다보륵빈솔여마상위。대비기우균방비（Mean square ratio ，MSR）화봉치상차（Peak difference ，PD）검측량충방법，해방법재호상관간우하유효제고약신호발현개솔。방진결과표명，강신호위－124 dBm시，해방법대－145 dBm약신호적검측개솔위83％。해방법대GPS접수궤약신호포획연구유실제의의。
Cross‐correlation interference is caused by C/A code correlation properties .It is an inevitable problem for GPS systems .And it has been one of the problems affecting the sensitivity of GPS receivers . To solve the problem ,a novel auto‐correlation detection method based on multi‐groups data comparison (MDC) is presented .In this method ,the Doppler frequency and code phase within several groups of data are compared to find the auto‐correlation peak .In contrast to the mean square ratio method and peak difference method ,the proposed method can improve the detection probability of weak signals effectively in the presence of cross‐correlation interference .The simulation results show that in the presence of one strong signal with -124 dBm power level ,the method can achieve an 83% detection probability for the weak signal with -145 dBm power level .Therefore ,it is useful for the acquisition of weak GPS signal .