Channel Adjustment for Performance Enhancement in Wireless Networks

Channel assignment is essential in wireless communications as it determines which channel to use for each pair of nodes. It has been extensively studied in literature, while all the existing works assume that the link exhibits equivalent performance for different channels and thus the objective is simply to allocate different channels to different wireless links. This assumption is however not always true in practice due to the frequency-selective-fading phenomenon. In this paper, we make a comprehensive study on the impact of the frequency selective-fading on the network design. Empirical results based on a 21 sensor node test bed and the theoretical analysis reveal the great opportunity for further performance gain by adjusting the channels when traditional channel assignment has been done. We propose a general Channel Adjustment Procedure algorithm and implement it on top of three traditional algorithms, namely PTC, MMSN and TMCP. Trace-driven simulations show that with a simple design, the network connectivity and the energy consumption can be easily improved by 20% with nearly no overhead.