Channel Quality Estimation and Rate Adaptation for Cellular Mobile Radio

We propose a technique to measure channel quality in terms of signal to interference plus noise ratio (SINR) for the transmission of signals over fading channels. The Euclidean distance (ED) metric, or suitable modifications thereof, associated with the Maximum Likelihood (ML) sequence are used as a channel quality measure. Simulations show that the filtered or averaged metric is a reliable channel quality measure which remains consistent across different coded modulation schemes and at different mobile speeds. The average scaled ML decoder metric can be mapped to the SINR per symbol. We propose the use of this SINR estimate for applications such as data rate adaptation, mobile assisted handoff (MAHO), and power control We particularly focus on the application of data rate adaptation and propose a set of coded modulation schemes which utilize the SINR estimate to adapt between modulations, thus improving data throughput.