Multi-Criteria Fuzzy-Based Handover Decision System for Heterogeneous Wireless Networks

Abstract

Seamless mobility is one of the most important issues considered in wireless mobile communications. Many researchers have developed numerous Handover Decision Systems (HDSs) to ensure seamless mobility between different Radio Access Technologies (RATs). With the appearance of real-time services in heterogeneous networks, numerous Quality of Service (QoS) parameters have to be included in the handover decision-making process. However, by increasing the number of input parameters in available HDSs, the algorithm execution time also increases. One way to decrease the algorithm execution time is to reduce the number of input parameters. However, this can lead to a degradation in the decision accuracy. In addition, most of the available handover decision algorithms comprise of QoS-related parameters but lack mobility and efficiency parameters. On the other hand, some algorithms consider mobility parameters as a handover decision criterion, but lack QoS-related parameters. In this paper, a fuzzy logic-based Handover Decision System design is proposed that allows for quick, intelligent, and comprehensive decisions during the handover procedure. Our proposed design uses a minimum number of fuzzy rules to select the best network for handover and to reduce the execution time. In addition, a total of eight decision parameters are chosen as the handover decision-making criterion, including QoS, mobility, and efficiency-related parameters. These parameters enhance the intelligence of the decision algorithm and enable a comprehensive decision for performing handover. Simulation results for our handover decision algorithm in terms of network selection performance show that it is superior to the Simple Additive Weighting, which is a non-fuzzy logic-based handover decision algorithm.