Resource Allocation Techniques for Cooperative AF Wireless Networks - Efficiency Fairness Trade-offs

Resource allocation is one of the critical problem in cooperative communication systems. The approach to allocate resources to maximize total network throughput favours sources with good channel condition. On the other hand, maxmin fair technique suffers from the loss of efficiency to a larger extent. Looking at futuristic wireless applications, the demand of users vary on wider spectrum. Allocation of a fixed amount of resources cannot satisfy such requirements. In this context, satisfaction of the user is more important criteria compared to common achievable targeted data rate. The user satisfaction is represented in term of utility based on some network performance criteria. This paper presents the concept of utility based resource allocation. The utility is defined as a function of data rate achieved by the user in the cooperative mode. Extensive simulation is carried out considering different utility functions that resemble the satisfaction of the user for variable data rate applications. The results show with the proposed utility based allocation significant fairness can be achieved with vary nominal decrease in efficiency. We have also investigated the efficiency-fairness trade-off for each of the utility function.