Handover Failure Rate Research Articles

A Cost-Based Adaptive Handover Hysteresis Scheme to Minimize the Handover Failure Rate in 3GPP LTE System

We deal with a cost-based adaptive handover hysteresis scheme for the horizontal handover decision strategies, as one of the self-optimization techniques that can minimize the handover failure rate (HFR) in the 3rd generation partnership project (3GPP) long-term evolution (LTE) system based on the network-controlled hard handover. Especially, for real-time operation, we propose an adaptive hysteresis scheme with a simplified cost function considering some dominant factors closely related to HFR performance such as the load difference between the target and serving cells, the velocity of user equipment (UE), and the service type. With the proposed scheme, a proper hysteresis value based on the dominant factors is easily obtained, so that the handover parameter optimization for minimizing the HFR can be effectively achieved. Simulation results show that the proposed scheme can support better HFR performance than the conventional schemes.

Handover Control Method Using Resource Reservation in Mobile Multimedia Networks

When handover events occur during the transmission of multimedia traffic, efficient handover control procedures and radio resource allocation are necessary to maintain the same QoS of transmitted multimedia traffic because the QoS may be degraded by additional delay and information loss. In this paper we propose a new handover control method for the next generation mobile multimedia networks, in which the handover setup process is done in advance of a handover request by predicting the handover cell from mobile terminal's current position. The handover procedures for real-time sessions are performed based on the handover cell information and the resource reservation condition. The radio resources in the estimated adjacent cells should be reserved and allocated to guarantee the continuity of the real-time sessions. We conduct a simulation model that is focused on the handover failure rate and packet loss rate. The simulation results show that our proposed method provides better performance than the previous methods.

Dynamic segmentation of cellular networks for improved handover performance

AbstractOne of the most important initial steps, inherent in the planning procedure of cellular networks, is their segmentation in operational parts that is performed at different levels corresponding to the hierarchy and topology of the network. The major goal of this procedure is the efficient deployment of the system and management of the distributed segmented parts while minimizing the signaling overhead in the network. As we show here, it can take place even during the operational phase of the network when certain shortcomings appear. In this work, we present an approach based on graph theory for the segmentation of cellular networks at the Base Station Controller (BSC) level that achieves a significant increase in the performance of the network. In particular, with the proposed method, both the handover attempts when a mobile station is moving to a cell belonging to a different BSC as well as the corresponding handover failure rate are decreased significantly, allowing for a continuous network upgrade. Copyright © 2007 John Wiley & Sons, Ltd.

Different queuing policies for handover requests in low Earth orbit mobile satellite systems

In this paper, a mobility model suitable for low Earth orbit mobile satellite systems (LEO-MSS's) has been presented, and its statistical parameters have been derived in order to evaluate the impact of the mobility on the performance of the fixed channel allocation (FCA) strategy. Moreover, we have foreseen that interbeam handover requests, which do not immediately find service, can be queued to reduce the handover failure rate. Two different queuing disciplines have been assumed: (1) the first-input-first-output (FIFO) scheme and (2) an idealized strategy that requires knowledge of the last useful instant (LUI) within which the handover procedure must be completed in order to rank the queued handover requests. An analytical approach has been developed to compare these queuing techniques, and its results have been validated through simulations.