Abstract:
The need for communication and other types of services is very high in daily bases and especially on disaster situation. The Device-to-device (D2D) communication as an underlay to cellular networks has gained increasing popularity as one of the main technology solutions for the enhancement of 5G network. the user equipment’s (UEs) in close proximity to each other, may communicate directly instead of through the eNodeB this helps to achieve better performance than that offered via eNodeB by offloading the eNodeB resources. this thesis focus mainly on D2D in a decentralized emergency scenario where the eNodeB is totally damaged, the main target was to find a suitable solution for discovery and selecting D2D pairs in disaster scenario using different algorithms simulated on Matlab program. As a result, the average number of D2D pairs that can be selected were compared with respect to the number of active devices and the probability of outage. After that, the effectiveness of using the D2D as a relay and its performance were evaluated in two modes, Amplify-and-Forward (AF) and Decode-and-Forward (DF) relaying. In the AF mode, the performance of the system with and without relay has been compared. Secondly the relay operated as DF, the performance of different error control mechanisms that can be used for relay networks, has been analyzed in terms of delay and transmission efficiency.
In the 1st phase, Device peer discovery the results showed that the outage probability can be decreased to about 33% when using the data rate algorithm compared to SINR and distance algorithm. While in the 2nd phase the results indicated that the overall system performance can be increased in terms of capacity, spectral efficiency and decreased latency when using the D2D as a relay.
