TOPSIS Based Multi-radio Access Scheme in Heterogeneous Wireless Networks

With the rapid development of various kinds of radio access technology, the trend of future network will be the heterogeneous wireless networks environment, where all kinds of networks coexist for their complementary characteristics. On the other hand, the rise of smart terminal and software defined radio contribute to the popularity of multi-mode terminals (MMTs) that can connect to several networks simultaneously. In this paper, we propose a TOPSIS based multi-radio access algorithm in heterogeneous wireless networks. MMTs determine candidate networks according to received signal strength (RSS) and access networks with better performance in terms of throughput, energy consumption, network load and cost by means of TOPSIS. Simulation results show that the proposed algorithm can enhance the throughput efficiently without consuming too much energy. Introduction The rapid development of mobile communication technology and broadband wireless access technology contribute to the increasing number of wireless communication traffic in recent years. Commonly, cellular networks support user mobility and seamless handoff but cost more. While broadband wireless networks charge lower price but only efficient in hotspots. There is not a network can satisfy all users’ demands, so that the trend of networks development is that all kinds of networks coexist. In addition, how to manage radio resource properly to meet the demands from users is a difficult issue. And an appropriate network selection method and resource allocation scheme is the effective approach for this problem. In [1], the authors proposed a fitting factor based network selection algorithm. In that paper, the fitting factor combine several factors that relate to the network selection and user access to network with the biggest factor value. A location and mapping information based network selection algorithm is proposed in [2]. The authors in [2] take network load into consideration and update network condition information periodically. However the adoption of positioning system makes it more complex. In [3], the authors proposed an automatic vertical handoff algorithm that take into consideration of RSS, traffic contents, users’ preferences and etc. [4] develops a network selection algorithm based on BP neutral algorithm and fuzzy logical. All the scheme mentioned above are single network selection. While the improvement of software and hardware technologies lead to the popularity of multi-mode terminals that equipped with multiple radio interfaces and can connect to several networks simultaneously. The authors in [5] proposed a utility based multi-service bandwidth allocation in HWNs where MMTs can simultaneously connect to several networks. A parallel transmission method adopting queueing theory is proposed in [6] for higher throughput. But both of the two papers don’t take care of energy consumption on which individuals pay more and more attention. In this paper, we put forward a TOPSIS based multi-radio access algorithm in heterogeneous wireless networks. MMTs determine candidate networks set according to RSS from available networks and active networks set based on TOPSIS method that considering energy consumption, throughput, cost and network load. Simulation results show that the proposed algorithm can enhance the throughput efficiently without consuming too much energy. 4th National Conference on Electrical, Electronics and Computer Engineering (NCEECE 2015) © 2016. The authors Published by Atlantis Press 634 The remainder of this paper is organized as follows. In Section 2, we introduce the heterogeneous wireless network model. The TOPSIS based multi-radio access networks selection algorithm in heterogeneous wireless networks is represent in Section 3. In Section 4, we evaluate the performance of the proposed algorithm and conclude the paper in Section 5. System model The heterogeneous wireless networks model is shown in Fig 1. It comprises Worldwide Interoperability for Microwave Access (WiMAX) networks, Universal Mobile Telecommunications System (UMTS) networks and Wireless Local Area Network (WLAN) access points. UMTS networks support wide coverage and user mobility but with low date rate. Compared with UMTS, WiMAX have higher date rate. WLAN provide high date rate and charge a low price, but are effectively only in hotspot areas. Users with traffic demand are in the whole area randomly.