System Capacity Maximization With Efficient Resource Allocation Algorithms in D2D Communication

In a device to device (D2D) communication underlaying cellular network, total system sum rate (capacity) can be improved if cellular user equipment's (UEs) and D2D pairs share resource blocks (RBs). We consider an optimization problem where the objective is to maximize the total sum rate of the system by sharing RBs among cellular UEs and D2D pairs while maintaining the quality of service requirements. We consider three approaches depending on the degree of sharing i.e., “One to One Sharing”, “One to Many Sharing”, and “Many to Many Sharing”. Most of the existing algorithms consider that sharing of RBs can only improve the total system sum rate. However, sharing of RBs between a cellular UE and a D2D pair can also decrease the total system sum rate. Considering this observation, we propose an algorithm based on the weighted bipartite matching algorithm which avoids such sharing and maximize the total system sum rate for the “One to One Sharing”approach. Moreover, We propose resource allocation algorithms for “One to Many Sharing”and “Many to Many Sharing”with a target to maximize the system capacity and also provide the analysis of the proposed algorithms. Through simulations, we find that our proposed algorithms outperform the existing algorithms in terms of maximizing total system sum rate. Our proposed algorithms also perform better in terms of total interference introduced due to the sharing of RBs among cellular UEs and D2D pairs.