Channel Capacity Loss Reduction with Channel State Detections

Adaptive modulation and coding schemes (MCS) are key components in the next generation wireless system to improve channel throughput by adaptively choosing the MCS according to channel states. However, due to channel feedback delay, processing delay, and scheduling delay, the channel state may change at the time of transmission and results in channel capacity loss. Simply using previous channel state without any detection approach to choose the MCS results in a large channel capacity loss. In this paper, we propose to use minimum mean-squared error (MMSE) and maximum a posteriori (MAP) approaches to detect the MCS at any given time and schedule the transmission using the detected MCS. Simulation results show that our proposed MCS detection approaches reduce channel capacity loss, compared with the case when no detection is used.