Fuzzy Vertical Handover Method Based on Sojourn Time Prediction in Vehicle Heterogeneous Networks

Abstract

The invention requests for protecting a type-II fuzzy vertical handoff method based on sojourn time prediction in a vehicle heterogeneous network. In the vehicle heterogeneous network, aiming at the problem that the handoff performance is reduced due to the facts that the sojourn time of a vehicle terminal is too short and the fuzziness and the randomness simultaneously exist in judgment parameters, influence of the sojourn time on the handoff performance is considered. When handoff judgement is carried out, the sojourn time of the terminal in various candidate networks is predicted at first;then, a corresponding type-II subordinating degree function is designed according to fuzziness and randomness factors in the sojourn time, the available bandwidth and the user access fee; furthermore,a type-II fuzzy inference system is constructed; and finally, an optimal handoff network is selected according to the system output. Experimental results show that: due to the fuzzy vertical handoffmethod disclosed by the invention, the average handoff time, the handoff failure rate and the ping-pong handoff time can be effectively reduced; and the system throughput is improved.

Description

technical field [0001] The invention belongs to a vertical switching method in a vehicle heterogeneous wireless network and belongs to the field of mobile communication. In particular, it concerns a method for vertical switching using dwell time prediction and type-2 fuzzy reasoning. Background technique [0002] With the development of intelligent transportation systems and the integration of heterogeneous wireless network technologies, high-speed mobile vehicle terminals are increasingly dependent on the network, and vehicle users hope to obtain the best network services anytime, anywhere, including stronger stability , higher bandwidth and lower costs, etc. In the vehicle heterogeneous wireless network, the vertical handover technology is the key technology to meet the user's network requirements. However, due to the high-speed mobility of vehicle terminals and the complexity and diversity of network environments, how to ensure the efficiency and stability of vehicle te...

AI Technical Summary

Problems solved by technology

However, in the sojourn time prediction model, the author simply regards the movement law of the terminal as a uniform linear motion, ignoring the influence of the change of speed and direction on the sojourn time after switching, and does not really reflect the movement law of the terminal

In addition, the above methods all use a type-one fuzzy system to deal with the ambiguity of the decision parameters, but in the actual decision-making process, there are not only fuzziness in the input parameters, but also randomness, such as measurement noise during measurement and time-varying nature of the network The randomness caused by , while the type-one fuzzy system cannot well describe the randomness of parameters

Therefore, the decision method based on the type I fuzzy system cannot effectively improve the quality of service after the terminal accesses the network

Images