Interoperability Criteria and Mechanisms for Seamless Inter-working between UMTS-HSDPA and HIPERLAN/2 Networks Enhanced with MIMO Techniques

摘要

The concept 4G wireless communication systems is to provide a user with a rich range of services across different radio access technologies, while maintaining the service's minimum QoS requirement, independently on the coverage area, mobility conditions, and using a single mobile terminal. To achieve this goal the need for interoperable heterogeneous wireless networks emerges. In this article we identify the challenges that arise when enhancing interoperability functionality to two different radio access networks. Specifically we will focus on inter-working UTRA FDD HSDPA and WLANs networks, as two strong candidates for composing the 4G environment. We also propose an interoperable architecture to achieve seamless inter-working between the aforementioned networks. The article also introduces two interoperable criteria that triggers interoperability based on the use of Cost functions. Namely, these triggers are the initial user assignment to the optimal network and inter-system handover. Each of the two triggers initiates a respective interoperability algorithm. Finally, In order to characterize the interoperability mechanisms behaviour and address an accurate QoS performance analysis, a software simulation platform has been developed. The platform is enhanced with MIMO transceivers and takes into consideration: network configuration, propagation conditions, fast fading, and service requirements.