On Achievable Data Rates and Optimal Power Allocation in Fading Channels with Imperfect CSI

Abstract

Achievable rates of communication systems with pilot-based channel estimation are investigated. Analytical expressions for the maximum achievable rates of such systems are derived for a given quality of estimation. It is shown how the classical waterfilling algorithm should be modified for the case of imperfect channel state information at the transmitter. The impact of the estimation scheme on achievable rates is studied and optimal frame lengths are found for analytical models with varying angular spreads.

Optimal training for non‐feedback adaptive modulation over Rayleigh fading channels

“…However, systems that rely on a channelfeedback link present some disadvantages because of the modeling complexity on one hand and its infeasibility on the other hand when the channel is fading faster than it can be estimated (or predicted) and fed back to the sender. Optimising the pilot placement, power allocation and modulation schemes in a pilot-based setup is an active area of research, whether in the case of a single receiver [9][10][11][13][14][15][16][17][18] or multiple receivers [18][19][20].…”