A Method for Network Assisted Relay selection in Device to Device Communication for The 5 G

Device to device communication is the interest of fifth generation where the User Equipments (UEs) are capable to directly communicate with other device with partial involvement of base station (BS). However, devices that are not in proximity area, communicate with other devices (relay). This relay selection is done by Base Station (Network Assisted). Network assisted Multihop device to device (D2D) communication increase the energy and spectral by using proximity service, hop gain and reuse of frequency in cellular communication. In this paper, we propose a relay selection scheme for secure Multihop (MH) communication. The propose scheme has two phases. In first phases search trust node among the neighbor based on trust node matrix and in second phase, trust node matrix has updated. This relay selection scheme not only considers a single parameter (SNR), also consider several parameters: maximum trust factor, minimum Estimated Service Time (EST), and the minimum interference SINR which provides reliable and secure communication from the malicious node. This relay scheme not only increases spectral and energy efficiency also provides a secure communication during relay selection. It has been compared with the main relay selection scheme and observed that our scheme gives up to 30 % better result in each case.