小型微型计算机系统
小型微型計算機繫統
소형미형계산궤계통
MINI-MICRO SYSTEMS
2010年
1期
186-189
,共4页
时域%相乘累加%抽取%串行搜索%捕获时间
時域%相乘纍加%抽取%串行搜索%捕穫時間
시역%상승루가%추취%천행수색%포획시간
time domain%addition and multiplication%sample%serial search%acquisition time
传统串行搜索算法在时域内对所有可能的频点和相位进行串行搜索,搜索的过程只需要加法和乘法运算,无论是在硬件还是软件中都容易实现,在GPS接收机设计中得到大量应用.但由于串行搜索算法在实际接收机中实现时,捕获过程需要大量的相乘、累加运算,需要较长的捕获时间.文中从降低相乘和累加运算个数入手,提出一种改进算法,使得捕获速度得到明显提高.利用MATLAB分别对传统的和改进的算法进行了算法仿真;根据信号捕获理论结合仿真实验结果,对两种算法进行了比较和分析,认为改进算法可以有效的应用于GPS信号捕获,而且提高了捕获的速度.该算法时于其它系统的伪随机码捕获也是适用的.
傳統串行搜索算法在時域內對所有可能的頻點和相位進行串行搜索,搜索的過程隻需要加法和乘法運算,無論是在硬件還是軟件中都容易實現,在GPS接收機設計中得到大量應用.但由于串行搜索算法在實際接收機中實現時,捕穫過程需要大量的相乘、纍加運算,需要較長的捕穫時間.文中從降低相乘和纍加運算箇數入手,提齣一種改進算法,使得捕穫速度得到明顯提高.利用MATLAB分彆對傳統的和改進的算法進行瞭算法倣真;根據信號捕穫理論結閤倣真實驗結果,對兩種算法進行瞭比較和分析,認為改進算法可以有效的應用于GPS信號捕穫,而且提高瞭捕穫的速度.該算法時于其它繫統的偽隨機碼捕穫也是適用的.
전통천행수색산법재시역내대소유가능적빈점화상위진행천행수색,수색적과정지수요가법화승법운산,무론시재경건환시연건중도용역실현,재GPS접수궤설계중득도대량응용.단유우천행수색산법재실제접수궤중실현시,포획과정수요대량적상승、루가운산,수요교장적포획시간.문중종강저상승화루가운산개수입수,제출일충개진산법,사득포획속도득도명현제고.이용MATLAB분별대전통적화개진적산법진행료산법방진;근거신호포획이론결합방진실험결과,대량충산법진행료비교화분석,인위개진산법가이유효적응용우GPS신호포획,이차제고료포획적속도.해산법시우기타계통적위수궤마포획야시괄용적.
The serial search algorithm searches for a satellite sequentially at each possible code delay and Doppler shift in time domain. Because only addition and multiplication operations are needed, it is easy to implement in time domain. This approach has been exten-sive applications in GPS receivers. Because the serial search algorithm has to do much glide correlation in a teal GPS receiver, this exhausting correlation also tends to be the main weakness of the serial search acquisition. To overcome the shortage of the serial search algorithm, the objective of the study is to shorten the correlation time, and a new algorithm is given. It can decrease the a-mount acquisition time efficient. If this algorithm is implemented in civil GPS receivers, the serial search algorithm will become more feasible and popular. The revisited algorithm aims at not only the GPS signal, but also is suitable for other CDMA systems.