| 摘要 |
PROBLEM TO BE SOLVED: To reduce the circuit scale of loop filter in the delay locked loop(DLL) of each finger at a RAKE system receiver. SOLUTION: At respective fingers 25A, 25B and 25C, the synchronous tracking of PN phase based on the deviation of frequency is performed by the DLL. The secondary loop filter part at loop filters 92A, 92B and 92C of respective fingers 25A, 25B and 25C is shared by the respective fingers 25A, 25B and 25C. Most of factors of frequency deviation are caused by a Doppler effect and since the similar frequency error occurs on all the paths in case caused by the Doppler effect, by commonly using the secondary loop filter part of loop filters storing frequency error components caused by the Doppler effect among the respective fingers 25A, 25B and 25C, the circuit scale can be reduced. |
