Patent ID: 6876694
Filing Date: 2005-04-05
Classification: H04B

Abstract:
1. A decoding apparatus for direct sequence spread spectrum signal for CDMA which comprises: memory means for storing “2k” pilot blocks from (n−(k−1)-th pilot block to (n+k)-th pilot block which includes a plurality of pilot symbols in a sequence of slots, where “n” is a non-negative integer and “k” is a positive integer; pilot symbol averaging means for averaging a plurality of received channels at a plurality of the pilot symbols in a slot; weight determination means for determining the weights which are used for obtaining a weighted average of the transmission channel estimation values per pilot block, where the weighted average is calculated over the “2k” slots and the weights are determined in accordance with the state of a transmission channel; multi-pilot block transmission channel estimation means for obtaining the transmission channel estimation values for the m-th information symbol in the n-th slot, on the basis of the weighted average where “m” is a non-negative integer; and transmission channel fluctuation compensation means for compensating the transmission channel fluctuation of the m-th information symbol in the n-th slot, on the basis of the transmission channel estimation values obtained by the multi-pilot block transmission channel estimation means, wherein said weight determination means narrows the range of dominant weights, when the transmission channel is unstable, while it enlarges the range of dominant weights, when the transmission channel is stable.