Multipath routing algorithm for device-to-device communications for public safety over LTE Heterogeneous Networks

One advantage of integrating small cells in cellular networks is to achieve Device to-Device (D2D) communications. The aim of performing D2D over small cells is to offload the Macro cells and also to assure the Public Safety (PS) exchange information especially during Disaster Management (DM), while the radio resources are unavailable totally or partially, or when the macro cell coverage doesn´t reach the emergency area. This paper presents a new solution for multipath routing for D2D communications for Public Safety over Heterogeneous Networks (HetNets). The proposed algorithm named Load Balancing Based Selective Ad hoc On-Demand Multipath Distance Victor (LBS-AOMDV) is an enhancement of the AOMDV scheme. One particularity of LBS-AOMDV is offering the information about the available bandwidth of each route within the multipath. Furthermore, it reduces the control traffic by decreasing the number of nodes receiving the RREQ requests. This is feasible since the RREQ senders select the node, which can receive the packets. In this way, LBS-AOMDV is a selective AOMDV. The simulation results show that LBS-AOMDV significantly reduces the number of RREQ in the network comparing with AOMDV. In addition, unlike AOMDV, only feasible paths are selected to form the multipath routes. In other words, the selected paths by LBS-AOMDV are able to meet the requirement of the Quality of Service (QoS) in the network.