Power Allocation and Bit Loading for Fixed Wireless MIMO Channels

Inhalt:
Power allocation and bit loading strategies can be considered in the context of diagonalized MIMO channels in order to maximize the achievable sum rate for a given sum transmit power. An algorithm, known as QoS based waterfilling, was specifically designed for such applications. In this contribution, based on the recently discovered mutual information maximizing mercury-waterfilling power allocation, we design a new strategy and compare its performance to the state of the art QoS based Waterfilling. It is shown that a simple modification of the latter algorithm can significantly improve the system performance with affordable complexity. Index Terms — Waterfilling, mercury/waterfilling, mutual information, Multiple-Input-Multiple-Output (MIMO), bit loading.