| 摘要 |
PROBLEM TO BE SOLVED: To reduce an arithmetic quantity. SOLUTION: The pilot signal of a CDMA(code dividing multiple connection) mobile communication base station is A/D transformed and furthermore transformed 13 to a complex base band signals I1 (k) and Q1 (k) by orthogonal transformation. The square sum of the absolute values of these is given DFT (discrete Fourier transformation) by an estimating part 31 and their phases are detected in addition. Thereby the symbol point of QPSK modulation by Ich and Qch is estimated, only samples near a symbol judging point in I1 (k) are fetched and the correlating arithmetic of the fetched group I1 (mk) (m = the frequency of (Ich))/(symbol frequency) and spreading codes IR (mk) and QR (mk) is respectively executed by correlating arithmetic parts 38 and 39 to control the generating phases IR (mk) and QR (mk) to make the square sum A' (mk) a peak. |
