Resource Management in WCDMA - Multiobjective Optimization Methodology: A Jumping Gene Approach - page 148

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Resource M anagement in WCDMA

7.1 Introduction
Due.to.the.recent.tremendous.demand.for.Internet.and.multimedia.services,.
third-generation. (3G). mobile. communication. systems. are. being. widely.
adopted..3G.systems.provide.wireless.Internet.services,.including.informa-
tion.and.Web.browsing,.mobile.banking,.mobile.shopping,.and.multimedia.
services.with.voice,.data,.and.video..Better.system.capacity.and.service.qual-
ity. are. now. available. due. to. the. high. data. transmission. rate. of. the. system.
owing.to.the.wide.bandwidth.allocated.[8,15,16,19].
The.transmission.speed.of.3G.systems.varies.with.different.situations..It.
is. 144. kbps. for. high-speed. movement. (e.g.,. users. in. vehicles);. 384. kbps. for.
low-speed. movement. (e.g.,. pedestrians);. and. 2. Mbps. for. stationary. status.
(e.g.,.users.sitting.in.an.office).[1,18,24],.supporting.both.packet-switched.and.
circuit-switched.services.
Many. different. proposals. have. been. suggested. by. different. orga-
nizations. [3,4,7,17,21],. and. they. are. summarized. in. Table 7.1 .. The. four.
radio. transmission. technologies—cdma2000,. WCDMA-FDD. (wide-
band. code. division. multiple. access. frequency. division. duplex). (UTRA-
FDD);.WCDMA-time.division.duplex.(WCDMA-TDD).(UTRA-TDD),.and.
Enhanced. Data. Rates. for. GSM. Evolution. (EDGE)—that. could. fulfill. 3G.
system. requirements. were. considered. [9,13,14,25].. However,. their. radio.
parameters. and. the. protocol. stack. with. respect. to. the. requirement. for.
global.roaming.were.incompatible.[18].
In.this.chapter,.the.WCDMA.system.is.the.focus..For.any.wireless.mobile.
communication. system,. the. interests. of. users. and. operators. are. somehow.
contradictory..From.the.users'.point.of.view,.they.hope.to.obtain.good.qual-
ity.of.service.(QoS)..The.QoS.reflects.the.signal.quality.of.connecting.users.
and. can. be. represented. in. a. number. of. ways,. such. as. bit. error. rate. (BER),.
received. bit. energy-to-noise. density. ratio. / 0

E N
b

,. and. so. on.. In. our. study,.

E b .was.considered.since.it.is.more.commonly.used.[10-12].
For. different. services,. such. as. voice,. data,. or. video. services,. a. minimum.
value. of. / 0

/ 0

E N
b

. (denoted. γ). is. to. be. speciied. for. each. type. of. service.. If. the.

E N
b

/ 0 .value.of.a.user.is.equal.to.or.greater.than.that.of.the.requested.service,.

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