Reducing Ping-Pong Handover Effect in LTE Mobile Networks Using TRIAS

Improving system performance in terms of data rate, mobility and cost is the scope of Long Term Evolution (LTE) system. In LTE networks the handover (HO) decision is performed by the evolved base station (eNB). The ping-pong movement in LTE is one of the most crucial problems which reduce the quality of the connection and degrade the performance of the handover. In this paper, the impact of ping-pong handover on inter eNB handover is investigated. The main object of the present work is to provide a method for reducing the number of ping-pong handover in the intra E-UTRA networks. A novel handover algorithm, based on keeping the old path between the source eNB and SGW/MME during the ping-pong movement and delaying the completion handover part, is presented. The ping-pong detecting algorithm for intra E-UTRA can be a tool to reduce the number of ping-pong handovers and control the demand of the network resources. Different values for the timer have been implemented and the probability of dropped calls and the ping-pong HO rates have been shown. Optimal timer value should be chosen carefully to reduce the probability of ping-pong HO and at the same time keep the dropped calls rate at lowest levels. Low and medium fixed user speed were implemented in this simulation mainly they are 25 km an hour and 70 km an hour. The analysis of the proposed algorithm showed that the rate of ping-pong handover can be reduced and, consequently, the handover quality indicator increased. Simulated results using TRIAS tools supported with NS2 simulator show that there is a significant reduction in the probability of the ping-pong handover when applied our proposed algorithm.