Cross-layer design benchmark for throughput maximization with fairness and delay constraints in DCF systems

This paper proposes a cross-layer design for the stations (STAs) in a distributed coordination function (DCF) network. By selecting the modulation scheme, coding scheme, and packet length of each STA in the network, the design aims to maximize the total throughput of all the STAs and satisfy the minimum throughput requirement or delay requirement of each STA, thus addressing the fairness and delay issues. The proposed scheme applies to the system where each STA employs a contention based channel access mechanism, Furthermore, unlike the existing optimization schemes, it takes two important factors, changeable data rate and changeable packet error rate (PER), into consideration. Using an existing Markov chain model to predict the performance of the STAs, we propose an approach that updates the selection of each STA sequentially, thus avoiding the large complexity from the exhaustive search. Many issues are discussed based on the numerical results, including how the approximations in our design affect the processing time and result of the design, how the change of one STA affects the performance of the other STAs, how the minimum throughput constraints affect the fairness and total throughput, how to select these constraints to satisfy the delay requirements, etc.