| 摘要 |
PROBLEM TO BE SOLVED: To provide a GPS receiver which can acquire GPS signals from a plurality of GPS satellites efficiently and rapidly, and carry out a positioning calculation more accurately. SOLUTION: Two of three kinds of PN codes among spreading code generators 534(1)-534(3) are input and added in an adder 536, and the added result is processed by using the FFT method and stored in a memory 538. The result value of the FFT process applied on the added PN codes stored in the memory 538 is multiplied by a result value of the FFT process applied on IF data (received data) stored in a memory 532, and the result of the multiplication is processed using the despreading method, thereby obtaining a correlation value. These processes are repeated, while changing the combination of PN codes to be added, and on the basis of these results, a synchronous acquiring process using a plurality of PN codes is carried out rapidly with fewer number of processings. COPYRIGHT: (C)2003,JPO |
