CHANNEL ESTIMATION USING PILOT SYMBOLS

摘要

A system for estimating the transfer function of a transmission channel such as the downlink channel in a CDMA system over which a pilot signal (P-CPICH) and a data signal (DPCH) are transmitted. The system includes: - at least one estimator (21, 22, 27; 24, 23, 25) for producing first and second channel estimates from the pilot signal and the data signals, and - a combination node (26) for combining the first and second channel estimates to obtain final combined channel estimates. The system includes an interpolator module (25) adapted for interpolating the second channel estimates over a basic estimation reference time (T) to produce equal numbers of channel estimates over the basic estimation reference time (T) derived from the data signal and the pilot signal respectively, and, possibly - rate adaptation modules (23, 27) adapted for mapping the channel estimates on the basic estimation reference time (T). The combination node is a summation node (26) producing the final combined channel estimates as a sum (26) of the first channel estimates and the interpolated second channel estimates.