Base Station Placement in WLANs - Multiobjective Optimization Methodology: A Jumping Gene Approach - page 178

8
Base Station Placement in WLANs
8.1 Introduction
Nowadays,. wireless. technology. has. penetrated. most. local-area. networks.
(LANs)..Wireless.local-area.networks.(WLANs).have.become.common.and.
popular..They.are.one.of.the.most.deployed.wireless.networks.in.the.world.
and.are.widely.installed.in.venues.such.as.homes,.schools,.enterprises,.hos-
pitals,. airports,. retail. outlets,. manufacturing,. corporate. environments,. and.
hot.spot.environments.[1,6,12,13].
There.are.many.reasons.why.WLANs.have.become.so.popular.[3-5,13,14],.
and.some.are.listed.next:
User mobility :.WLANs.offer.free.movement.to.users.who.do.not.want.
to. or. even. cannot. access. the. network. at. ixed. locations. (e.g.,. class-
rooms,.libraries,.offices,.shopping.centers,.factories,.etc.)..Thus,.they.
can.bring.convenience.to.users.
Flexibility and scalability :. WLANs. can. be. flexibly. adjusted. to. differ-
ent.network.topologies.to.fulfill.specific.applications.and.installations..
Unlike. wired. LANs,. the. topology. of. WLANs. can. be. easily. modiied.
if. necessary.. Furthermore,. only. authorizations,. but. not. cables,. are.
required.for.adding.users.to.WLANs..If.WLANs.are.to.be.expanded,.
only.additional.access.points.and.extension.points.are.required.
Wiring dificulty :.Floors.in.some.buildings.(e.g.,.factories,.places.con-
taining. hazardous. materials). or. locations. outdoors. are. not. suitable.
for. installing. wires. for. wired. LANs.. In. contrast,. there. are. many.
fewer.constraints.for.WLANs.
Low overall cost of operation :.The.wiring.cost.in.a.wired.LAN.depends.
on.the.total.number.of.stations.that.it.can.support.and.the.distances.
between.the.stations.and.the.hub..In.contrast,.there.is.no.wiring.cost.
for. WLANs. regardless. of. the. total. number. and. location. of. stations..
Furthermore,. their. installation. and. maintenance. costs. are. cheaper.
compared. to. those. incurred. by. traditional. additions,. deletions,. and.
changes.of.wired.LANs.
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