LIMITS OF CAPACITY INCREASE IN CELLULAR NETWORKS DUE TO THE IMPLEMENTATION OF DEVICE TO DEVICE COMMUNICATIONS

Abstract

(D2D) Device to Device communications is a new approach which proposes the separation of data planes and control, thus revolutionizing the traditional methods of communication. This approach is capable of increasing the capacity of the system significantly by providing three types of gain: proximity gain, hop gain and reuse gain, thus it is considered as an approach for the next generation of cellular networks. However, this type of communications can cause interference within the cellular network if not properly designed. To investigate the possible increase in the system capacity and reduce the effect of interference, a three-step algorithm was proposed and evaluated against three matrices: throughput gain, user capacity and access rate. Â The simulation results showed that as the D2D pair gets closer to each other the access rate increases and it can reach up to 98%. Also the throughput gain is directly effected by the distance between the D2D pair as it can reach up to 100% when placing the D2D at an area of 100 m2 and decreases gradually when increasing the distance, while placing the D2D pair at the edge of the cell will result in higher throughput gain as it can reach up to 130% at D2D to CU ratio equals to 1. Finally, the simulation results proved that it is possible to add an extra 60% of the already existed users when using the D2D communication within the cell.