Research Of Heterogeneous Wireless Network Access Selection Algorithm

With the development of wireless communication technology, the integration of the network has become an inevitable trend. The wireless communication network is formed by a variety of network overlay fusion, that is, heterogeneous wireless network. In the social life,the user has been able to pick up the phone, through the 3G or 4G network for voice communication, you can also watch the video through the WLAN network, to experience a wide range of services. Communication services are no longer limited to a single network environment, which is the benefits of network convergence.For the network itself the integration of the network can not only expand the capacity of the network, but also can improve the comprehensive utilization of resources; for users,you can be free to switch between multiple networks, you can also enjoy more services. The convergence of wireless networks forms heterogeneous wireless networks. The choice of network access in heterogeneous wireless network environment is an important direction of research in the field. Different access selection strategies, network resource utilization and user service experience are different. Therefore, the development of network access options to select the specific strategy is essential.So far the network access selection algorithm of the heterogeneous wireless has its advantages and disadvantages. Among them, Fuzzy logic will imitate the manner of human brains, and hence it can make fuzzy comprehensive judgments. As a benefit, it can solve the fuzzy information problem which is unsolvable to conventional reasoning method. When the versatile of different requirements from users and the variability of the heterogeneous wireless network itself, it is complicated to establish a model analysis of heterogeneous networks due to the dynamic changes of their environmental parameters. The fuzzy logic algorithm can be applied to the above situation. In this paper, based on a careful analysis of previous existed access-technology selection algorithms for heterogeneous wireless network,a further improved algorithm with the aid of both the entropy weighting strategy and fuzzy logic is proposed. First, in the design process of the fuzzy controller, it is necessary to formulate the corresponding fuzzy reasoning rules according to the expert experience, and form the fuzzy rule base. However, When the number of concerned parameters increases, the size of the fuzzy reasoning rule base will rapidly increase. For the problem, this paper uses the analytic hierarchy process to solve the network attribute weight, according to the network attribute weight to select the network attribute as the input variable, the establishment of the new fuzzy rule base. Due to the decrease of the network decision attribute, the number of rules in the fuzzy rule base will be reduced to achieve the purpose of optimizing the fuzzy rule base. Secondly, in the process of using the fuzzy logic algorithm, the fuzzy rule reasoning and the fuzzy rule reasoning according to the expert experience. The algorithm has strong subjectivity. In order to solve the problem, the fuzzy logic algorithm is combined with the entropy method, and the entropy weight method is an objective weighting method. When the two algorithms are combined and selected, the subjective and objective methods are combined to evaluate the alternative networks, and the optimal network is selected. Finally,we implement a range of simulations for the verification.