Patent ID: 7277472
Filing Date: 2007-10-02
Classification: H04B,H04L

Abstract:
1. A method for estimating a flat fading channel in a CDMA communication system, said method comprising: a. inputting a despreaded channel signal corresponding to each transmission path to a respective one of an adaptive lattice filter of a receiver and calculating an estimated value of a received signal at a node n at time n, wherein said respective one of the adaptive lattice filter is used to predict channel fading according to LS rule; b. adding together a measurement result of a branch metric corresponding to each transmission path and obtaining survived paths at time n by using a maximum likelihood detection technique to perform a Viterbi algorithm according to a value of predicted channel fading; c. demodulating a signal estimation result obtained from the survived paths according to corresponding received signals to obtain an estimated value of a channel fading at time n; d. adjusting a coefficient of each of the adaptive filters, and then estimating a channel at time n+1; and e. repeating steps a˜d till all survived paths converge into one path at a pilot symbol of a time slot, wherein a phase of the nodes in said transmission path corresponds to an estimated phase value for transmitted signals.