SYSTEM AND METHOD FOR MEASURING CHANNEL QUALITY INFORMATION

摘要

A system and method to measure channel quality in terms of signal to noise ratio for the transmission of coded signals over fading channels. A Viterbi deco der metric for the Maximum Likelihood path is used as a channel quality measure. Thi s Euclidean distance metric is filtered in order to smooth out short term variatio ns. The filtered or averaged metric is a reliable channel quality measure which rema ins consistent across different coded modulation schemes and at different mobile speeds. The filtered metric is mapped to the signal to noise ratio per symbol us ing a threshold based scheme. Use of this implicit signal to noise ratio estimate is u sed for the mobile assisted handoff and data rate adaptation in the transmitter.