Queue and Channel-Based Aloha Algorithm in Multichannel Wireless Networks

Cross-layer Aloha protocols that exploit the channel diversity when accessing the spectrum became popular in recent years, due to their capability to increase the user rates as compared to classic Aloha-type protocols. Existing algorithms, however, suffer from significant performance degradation in terms of queue load balancing, which makes them inefficient in practical systems. In this letter, we develop a novel queue and channel based Aloha (QCA) algorithm to solve this issue. In QCA, each user trades off between the channel state and the queue state to increase the rate while keeping the queue load small. Strong performance of the algorithm is demonstrated theoretically and numerically.