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The tremendous growth of the mobile users’ population coupled with the bandwidth requirements of new cellular services is in contrast to the limited spectrum resources that have been allocated for mobile communications. The objective of channel allocation is to assign a required number of channels to each cell such that efficient frequency spectrum utilization is provided and interference effects are minimized. | Handbook of Wireless Networks and Mobile Computing Edited by Ivan Stojmenovic Copyright 2002 John Wiley Sons Inc. ISBNs 0-471-41902-8 Paper 0-471-22456-1 Electronic CHAPTERS Heuristics for Solving Fixed-Channel Assignment Problems HARILAOS G. SANDALIDIS and PETER STAVROULAKIS Telecommunication Systems Institute Chania Crete Greece a i RomenN The tremendous growth of the mobile users population coupled with the bandwidth requirements of newcellrCar servicesis inconhasttothe limited spectrum resources that havebeenallocatedfor mobilecommumcations.Theobjective of channel allocation is to assign a required number of channels to each cell such that efficient frequency spectrum utilization is provided and interference effects are minimized. A fixed-channel assignment problem models the task of assigning radio spectrum to a set of transmitters on a permanent basis. The formulation of this problem as a combinatorial one in the beginning of the 1980s ledanmnberofcomputer scientists and operations research scientists to try and find optimal solutions. Heuristic techniques can give near-optimal solutions at a reasonable computational costfor algorithmically I tnplaxaaUma-conouming problemssnch as chaimelassignment.An overviewofthu ocostbasic heurirtic fixmP-chamoeP as-l-mmcnt tchama amthc liSnmarueu éctheoubjectof-Osa study Pt2 REROURCE MANAGEMENTTASKP CellularfaOie-cstnmcrelb cm asuO-equenOaitocutinncneoeuonoUcha-anuSa tlnonaaontf rovfrumecegtoni tiueX celllsallocalc U cgio-inoC fndiochamiRo. Neiahbol mgcePlsut p n n -cmitac i ge nt i sdt ite nmbn completpUymitemntchannuls.helimtting theooverago utea vit onihuepundariea of e neU 1i p x of chaIme-smpybeneuPtocovuc diU 10100 0x11. SPpU areoeppralepfrom pneAnptherho some distance. Cellular mobile communication systems are characterized by their high degree of capacity. Consequently they have to serve the maximum possible number of calls though the nrmiber onaeennelseercell isCimited.On the other hand cells in the same cluster .