Study Group report 2005: frequency reassignment (Motorola)
This is the final report on frequency reassignment, brought to ESGI53 by Motorola. Click on the link at the bottom to download the full report as a pdf document.

Report authors
John Billingham (University of Nottingham)
Robert Leese (Smith Institute)
Hannu Rajaniemi (University of Edinburgh)

Introduction
Finding the optimal frequency assignment of a network of cellular phone base stations is known to be a hard – in fact, NP-hard – problem. The purpose of the Study Group report is to address a related question. During the operation of a cellular network service it often becomes necessary to implement a new frequency assignment plan in response to changes in traffic or perhaps after new hardware has been installed. Usually the switch to the new plan involves a global reset of the network which results in a break in the provided service. Hence, it is desirable to investigate the possibility of dynamic reassignment – i.e., a method which can be used to move over to the new plan while the network remains in operation. It turns out that this problem can be naturally formulated in terms of graph recolouring. The report presents a simple but effective algorithm for dynamic reassignment based on a straightforward approach of search and random colouring.

Download 'Motorola-report.pdf' (908 Kb).