APPLICATIONMONITORING AND CONTROL3. Power down all unused sectors in the base station.4. Maintain status monitoring to receive comm<strong>and</strong> statusupdates.5. Power up when minimal load activity session activitylapses.This type of flexibility is likely to be implemented in a stagedapproach in a real network, as one wireless base station afteranother is powered down (or removed from the network in therental model) as the traffic load decreases, until a minimal configurationis reached. As an example, suppose that in the networkshown in Figure 1 that 18 out of the 26 base stations can be powereddown or removed from this network. This leads to a newnetwork with the remaining base stations covering an exp<strong>and</strong>edarea as shown in Figure 2.Figure 2Powering down (or removing) these 18 base stations can providea power savings in the network, helping lower the operator’soperating expenses. To accurately estimate the power savings,one needs to note that the base stations remaining in the networkwill experience an increase in power due to base stations beingremoved from the network. The additional range needed to supportgeographical coverage for h<strong>and</strong>sets formerly supported bybase stations that have been removed from the network requiresextra transmission power. Using an industry st<strong>and</strong>ard model presentedin Wireless Communications: Principles <strong>and</strong> Practices [1](<strong>and</strong> assuming an environmental factor of 2), the signal powerrequired to travel across a distance d from a transmitter to receiveris described by Equation 1.p ij~ (d ij) 2 (1)Equation 1The significance of this model is that if the transmission distanceis doubled by a factor of two, the power increases by a factorof four. However, this power increase is limited to the radiomodule of the wireless base station, which accounts for roughly30 percent of the wireless base station power consumption. Aquick power savings calculation reveals that the power consumptionof the minimal network shown in Figure 2 will be a littleunder 60 percent of the peak load network shown in Figure 1,which allows for an over 40 percent power savings during theoff-peak times.Summary3G will generate new data service requirements that will enablewireless operators to stem their ARPU decline. Given the constantlyevolving wireless st<strong>and</strong>ards <strong>and</strong> the recognized need forgeographic customization, programmable technologies are rapidlyreplacing traditional ASICs. This trend will continue as basestation designs offer additional flexibility to address more <strong>and</strong>more complex technical requirements for delivering next generationdata services. At the same time, base stations must maintainthe versatility to avoid obsolescence or limited deploymentby adapting to st<strong>and</strong>ards changes <strong>and</strong> geographic variations. Inaddition, these programmable technologies also offer operatorsan opportunity for cost savings by using the programmable flexibilityto manage their networks through the service periods.David Gamba is senior marketing manager for the StrategicSolutions Marketing Group at Xilinx. In this role, David isresponsible for outbound marketing for all vertical marketssupported by Xilinx solutions. David joined Xilinx in 2004 <strong>and</strong>brings more than eight years of experience in the semiconductorindustry, where he served in a variety of marketing <strong>and</strong> salesroles including technical sales, product definition, <strong>and</strong> technicalmarketing. Prior to Xilinx, David held various positions atAeluros, Conexant, <strong>and</strong> Altera. He holds a bachelor’s degreein electrical engineering from UCLA, a master’s degree inelectrical engineering <strong>and</strong> computer science from UCBerkeley, <strong>and</strong> an MBA degree from Stanford University.References[1] Dr. Ted Rappaport, Wireless Communications:Principles <strong>and</strong> Practices, 1996, Prentice HallFor further information, contact David at:Xilinx2100 Logic Dr. • San Jose, CA 95124Tel: 408-879-6146 • Fax: 408-371-4926E-mail: david.gamba@xilinx.comWebsite: www.xilinx.com46 / <strong>CompactPCI</strong> <strong>and</strong> <strong>AdvancedTCA</strong> <strong>Systems</strong> / June 2005
RSC# 47 @www.compactpci-systems.com/rsc<strong>CompactPCI</strong> <strong>and</strong> <strong>AdvancedTCA</strong> <strong>Systems</strong> / June 2005 / 47RSC# 47 @www.compactpci-systems.com/rsc