Departmental Papers (ESE)


Improved channel assignment algorithms for cellular networks were designed by modeling the interference constraints in terms of a hypergraph [1]. However, these algorithms only considered cochannel reuse constraints. Receiver filter responses impose restrictions on simultaneous adjacent channel usage in the same cell or in neighboring cells. We first present some heuristics for designing fixed channel assignment algorithms with a minimum number of channels satisfying both cochannel and adjacent channel reuse constraints. An asymptotically tight upper bound for the traffic carried by the system in the presence of arbitrary cochannel and adjacent channel use constraints was developed in [2]. However, this bound is computationally intractable even for small systems like a regular hexagonal cellular system of 19 cells. We have obtained approximations to this bound using the optimal solutions for cochannel reuse constraints only and a further graph theoretic approach. Our approximations are computationally much more efficient and have turned out to track very closely the exact performance bounds in most cases of interest.

Document Type

Journal Article

Date of this Version

September 2002


Copyright 2002 IEEE. Reprinted from IEEE Transactions on Vehicular Technology, Volume 51, Issue 5, September 2002, pages 954-967.
Publisher URL: sNumber=24316&puNumber=25

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Adjacent channel interference, cellular systems, channel assignment algorithms, cochannel interference, graph models, hypergraph models



Date Posted: 15 November 2004

This document has been peer reviewed.