دانلود رایگان مقاله در پیکربندی منابع رادیویی در فرکانس فراکشنال مجازی استفاده مجدد از شبکه تلفن همراه

Abstract

Virtualization of wireless networks holds the promise of major gains in resource usage efficiency through spectrum/radio resources sharing. Unlike the case in wired networks, achieving high capacity, providing effective isolation, and customization of the network requires intelligent configuration of wireless resources due to the effects of interference. In this paper, we focus on how to configure the “over-the-air” part of virtual wireless networks to enable simultaneous use of radio resources that overlap geographically. A configuration framework is proposed based on an infrastructure cellular network that employs fractional frequency reuse (FFR) and Multiple-input Multiple-output (MIMO) to combat interference. Multiple scenarios are examined that include various network sizes and base station distances. Five radio resources configuration cases are developed and investigated with each of these scenarios for a number of parameter settings (e.g., transmit power, MIMO degree). From the analysis of capacity data obtained from simulations, we observe some general trends in the aggregate spectral efficiency, and more importantly, a variety of tradeoffs between service providers (SPs) or virtual network operators. Based on these tradeoffs, we create configuration maps using which, a network resource manager can select specific network configurations (transmit power, MIMO, etc.) to meet the demand and capabilities of SPs and their subscribers.

6. Conclusions

In this paper, we use simulations to examine the problem of radio resource configuration when wireless networks are virtualized. We evaluate several scenarios with several spectrum sharing cases that include FFR. The paper provides a framework for a resource manager to configure radio resources between two different SPs operating in the same geographical area. The configuration of a virtualized wireless network is unlikely to have a definite “closed form” single solution. Proper configuration depends on the network architecture, capabilities of the network/end-devices and demands of the players, and it changes dynamically. Reasonable configurations appear to be capable of leading virtualization towards higher efficiencies, better isolation across SPs, and customization of services. Configurations investigated are references for future cellular networks with similar advanced technologies.