Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.comHow to Use aSpectrum Anay!er"i-Spy #ersion $ast Up%ate 2011.0&.'01.'.01()*ecti+es$earn how to use a spectrum anay!erCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com2"hat is a Spectrum Anay!erSometimes we nee% to see the eectromagnetic wa+es use% )y wireess systems to sen% %ataSimiar to an oscioscope that is use% to e,amine an eectrica signa as it +aries o+er time- a spectrum anay!er is use% to capture an% %ispay the wa+e.orms o. ra%io .re/uency signasCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'"hat is a Spectrum Anay!er0his is a graphica representation o. the signa1s ampitu%e or signa energy as a .unction o. .re/uency- not time0he spectrum anay!er is to the .re/uency %omain as the oscioscope is to the time %omainCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com2"hat is a Spectrum Anay!er"ith an oscioscope when measuring in the time %omain- a .re/uency components o. the signa are summe% together an% %ispaye%3n the .re/uency %omain- compe, signas that are ma%e up o. more than one .re/uency are separate% into their .re/uency components- an% the signa e+e at each .re/uency is %ispaye%Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com4"hat is a Spectrum Anay!er0he spectrum anay!er is a passi+e %e+ice3t %oes not %o anything to the signa3t *ust %ispays itCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com50ypes o. Spectrum Anay!ers0here are two )asic types o. spectrum anay!ersStan%aone UnitsUS6 6ase%Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com7Stan%aone UnitCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com8Signa Patterns$et9s oo: at some common signa patterns as seen on a spectrum anay!erHere are the ;M ra%io stations in the D;" areaCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com&Signa PatternsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com10"i;i SignasUni:e the other signas the DSSS < Direct Se/uence Sprea% Spectrum signa use% )y "i;i systems is characteri!e% )y a ow e+e signa that is sprea% o+er a wi%e rangeAs such it oo:s +ery much i:e transient noiseCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com11"i;i Signas0o actuay see this type o. signa on the spectrum anay!er the pea: ho% .unction o. the spectrum anay!er must )e acti+ate%0his .unction :eeps each signa on the screen as ong as the pea: ho% .unction is acti+ate%6y %oing this a pattern o. the signa )egins to appearCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com12"i;i Signas0o see the entire 3SM &00 MH! span .rom &02 to &28 MH! set the center .re/uency to &14 MH!Set the span contro to pro%uce a span o. ' MH!0o use a spectrum anay!er in the 2.2=H! )an% .or 802.11) signas set the center .re/uency to 22'7 MH! an% a 4 MH! per %i+ision spanCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com1'"i;i Signas0he spectrum anay!er %ispay wi )e centere% on 802.11) channe 5>ach o. the .i+e +ertica gri% ines on either si%e o. the center one wi represent that respecti+e channes .rom channe 1 on the .ar e.t to channe 11 on the .ar right0o see the entire U?33 4.' =H! span .rom 4.240 to 4.'40 =H! set the center .re/uency to 4'00 =H!Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com12"i;i SignasSet the span contro to pro%uce a span o. 10 MH!0o see the entire U?33 4.8 =H! span .rom 4.724 to 4.824 =H! set the center .re/uency to 4774 =H!Set the span contro to pro%uce a span o. 10 MH!Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com14"i;i Signas0o see the entire U?33 4.' =H! span .rom 4.240 to 4.'40 =H! set the center .re/uency to 4'00 =H!Set the span contro to pro%uce a span o. 10 MH!Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com15Signa PatternHere is an e,ampe o. a DSSS signaCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com17Signa PatternCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com18Stan%aone Units0he main pro)em with stan%aone units is the cost0hey typicay range .rom @'-000 to @20-000Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com1&US6 Anay!erA ower cost option is the US6 spectrum anay!erA e,ampe o. these is the unit .rom Meta=ee:0hese cost .rom @200 to @500;or e,ampeCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com20US6 Anay!erCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com213nter.aceHere is the inter.aceCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com223nter.aceCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com2'0ime o. Capture0he mo+ing ine at the )ottom shows how ong the %ata has )een capture%0his time ine can )e oc:e% into a speci.ic amount o. time )y %ragging each o. the en%point coore% %ots inwar%0his aows a roing %ata coection where the %ata is o+erwritten with new %ata .or the time perio% seecte%Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com220ime o. CaptureCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com24Spectra #iew0he top thir% o. the inter.ace is the Spectra #iewCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com25Spectra #iewCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com27Coor 6ars0he coor )ar at the top o. the Spectra #iew shows the signa strength0he num)er on the e.t is the wea:est seen0he num)er on the right is the strongest seen0he coors in this +iew represent the signa strengthCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com28#ertica Stripes#ertica stripes in the top section in%icate a stea%y signa0he coor o. the stripes show how strong the signa is3n this case it shows a wea: )ut constant signaCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com2ertica StripeCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'00opographic #iew0he mi%%e section- the 0opographic #iew- shows the signa patterns again using a coor co%e(n the e.t is the signa strength in %6sCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'10opographic #iewCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'2Panar #iew0he )ottom pane is the Panar #iew3t shows theCurrent signa in yeowA+erage signa in greenMa,imum signa in )ue0he signa strength in %6s is shown on the e.tCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com''Panar #iewCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'23n%icators>ach o. these three can )e turne% o.."hen oo:ing .or inter.erence it is )est to turn o.. a e,cept the yeow current signa strength in%icatorCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'43n%icatorsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'5Signa SignaturesSome signa signatures can )e accesse% )y cic:ing on the Signatures ta) on the right si%e o. the inter.ace0hese can )e seecte%- then mo+e% o+er the signa shown to try to i%enti.y a patternCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'7Signa SignaturesCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'8Signature MatchingCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com'&?etwor:s (+erayAny wireess ?3C in the same unit can )e use% to o+eray the 802.11 wireess networ:s it sees o+er the spectrum %ispaySeect the "i;i ta)- then cic: Start Scanning(nce the networ: ist is compete- seect the ones to show on the spectrum %ispay )y cic:ing the )o,es6y ho+ering o+er the ist some %etais can )e seenCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com20?etwor:s (+erayCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com21?etwor:s (+erayCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com22?etwor:s (+erayCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com2'?oise0he ony in%ication o. the noise e+e in the area is the ow e+e signa shown at the )ottom o. the 0opographic #iewCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com22?oiseCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com24Sampe Aecor%ingsSome sampe recor%ings o. common networ: +iews can )e %ownoa%e% .or comparison purposeCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com25$ong 0erm Data Capture3n or%er to capture intermittent inter.erence Chanay!er may )e e.t running .or a perio% o. time0his wi re/uire a)out 40M6 o. %is: space per 10 hoursA speci.ic part o. the capture can )e +iewe% )y a%*usting the time ine )y %ragging each o. the en%point coore% %ots inwar%Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com27$ong 0erm Data Capture0he entire capture can )e e,amine% )y si%ing the section )etween the %ots )ac: an% .orth0he time ine can aso )e %ou)e cic:e% to *ump to that time perio%Copyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com28Chanay!er $ite0here is a secon% +ersion o. Chanay!er cae% Chanay!er $ite"hy is not cear0his +ersion shows the %ata in a 'D +iew;or e,ampeCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com2&Chanay!er $iteCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com40Chanay!er $ite0his +iew is +ery use.u when trac:ing %own %e+ices?otice in the screen shot a)o+e the re% pea:As you mo+e coser an% coser to the %e+ice the amount o. re% wi increaseAs you mo+e away .rom it- the re% wi %ecreaseCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com413nterpreting the Aesuts3n a Septem)er 2011 we)inar ;u:e using their AirMagnet spectrum anay!er pro+i%e% some e,ceent e,ampes o. how to interpret the resuts o. typica spectrum captures$et9s see what they ha% to sayCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com423nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com4'3nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com423nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com443nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com453nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com473nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com483nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com4&3nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com503nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com513nterpreting the AesutsCopyright 2010-2011 Kenneth M. Chipps Ph.D. www.chipps.com52