A NOVEL TECHNIQUE FOR INCREASING USER CAPACITY FOR MOBILE COMMUNICATION BASED ON SMART ANTENNA

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1 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology A NOE TECNIQUE FO INCEASING USE CAPACITY FO MOBIE COMMUNICATION BASED ON SMAT ANTENNA rish T.S Studet, M.Tech Deprtmet of E&C. U.B.D.T College of Egg, Dvgere, Krtk, Idi. Emil id: hrshujji@gmil.com. T.D. Shshikl Assistt Professor, Deprtmet of E&C. U.B.D.T College of Egg, Dvgere, Krtk, Idi. Emil id: itgppm77@gmil.com. Abstrct Smrt tes re widely used i wireless mobile commuictios s they c icrese the chel cpcity d coverge rge. I smrt te, to locte the desired sigl, vrious directio of rrivl (DOA) estimtio lgorithms re used. I this pper, ew Eige ector lgorithm for directio of rrivl (DOA) estimtio is developed, bsed o eige vlue decompositio d ormliztio of covrice mtrix. Ulike the clssicl Mximum ikelihood Method (MM) d Mximum Etropy Method (MEM) lgorithms the proposed method oly ivolves the determitio of oise subspce eige vectors which provides better resolutio d bis s compred to existig DOA lgorithms. I order to reduce hdover dely cused by hdover filure i cellulr etworks rdio resource is reserved for hdover users ot oly t trget cell, but lso t prepred cells. The discussed scheme reserves resource pool t prepred cells which is shred mog multiple users. The compriso of the probbility of successful hdover for both trditiol d proposed ovel scheme is discussed for both FDMA-TDMA d FDMA-SDMA bsed combied multiple ccess systems. cpcity d performce beefits th stdrd tes becuse they c be used to customize d fie-tue te coverge ptters to the chgig trffic or rdio frequecy (F), coditios[]. A smrt te system t the bse sttio of cellulr mobile system is depicted i Fig.. It cosists of uiform lier te rry for which the curret mplitudes re djusted by set of complex weights usig dptive bemformig lgorithm []. Idex Terms rry sigl processig, directio of rrivl, MUSIC, MM, MEM, hdover. M I. INTODUCTION OBIE COMMUNICATION etworks fce ever-chgig demds o their spectrum d ifrstructure resources. Icresed miutes of use, cpcity-itesive dt pplictios, d the stedy growth of worldwide wireless subscribers me crriers will hve to fid effective wys to ccommodte icresed wireless trffic i their etworks. owever, deployig ew cell sites is ot the most ecoomicl or efficiet mes of icresig cpcity. Wireless crriers hve begu to explore ew wys to mximize the spectrl efficiecy of their etworks. Smrt tes[] hve emerged s oe of the ledig iovtios for chievig highly efficiet etworks tht mximize cpcity d improve qulity d coverge. Smrt tes provide greter All ights eserved 0 IJACET Fig.. Smrt Ate System. The dptive bemformig lgorithm optimizes the rry output bem ptter such tht mximum rdited power is produced i the directios of desired mobile users d deep ulls re geerted i the directios of udesired sigls represetig cochel iterferece from mobile users i djcet cells. Prior to dptive bemformig, the directios of users d iterferes must be obtied usig directio-of rrivl estimtio lgorithm. There re severl types of directio of rrivl lgorithms like Clssicl (MM, MEM) d Subspce bsed (MUSIC) methods. These lgorithms re implemeted i DSP processor of smrt te for rel-time workig i prcticl wireless eviromet. 38

2 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology The pper is orgized s follows: Sectio II provides brief iterture survey for proposed reserch.sectio III describes the theory of smrt te systems Sectio I describes dely d sum (Mximum ikelihood) method. Sectio describes Mximum Etropy Method; Sectio I describes Multiple Sigl Clssifictio (MUSIC) method for Directio of rrivl. Sectio II describes esource reservtio scheme. Sectio III presets performce results for the smrt te Directio of Arrivl lgorithms, esource reservtio cpcity d results of successful probbility of hdover for trditiol d proposed methods. Filly, coclusios re give i sectio IX. II.ITEATUE SUEY. Smrt Ates This referece provides bsic iformtio bout Smrt tes d its chrcteristics. Smrt tes hve the property of sptil filterig, which mkes it possible to receive eergy from prticulr directio while simulteously blockig it from other directio. This property mkes smrt tes very effective tool i detectig d loctig uderwter source of soud such s submrie without usig ctive sor. The cpcity of smrt tes to direct trsmittig eergy towrd desired directio mkes them useful for medicl digostic purposes. This chrcteristic lso mkes them very useful i ccelig uwted jmmig sigl. I commuictios system, uwted jmmig sigl is produced by trsmitter i directio other th the directio of the desired sigl. For medicl doctor tryig to liste to the soud of pregt mother s hert, the jmmig sigl is the soud of the bby s hert. Processig sigls from differet sesors ivolves mplifyig ech sigl before combiig them. The mout of gi of ech mplifier dicttes the properties of the te rry. To obti the best possible ccelltio of uwted iterfereces, the gis of these mplifiers must be djusted. ow to go bout doig this depeds o my coditios icludig sigl type d overll objectives. For optiml processig, the typicl objective is mximizig the output sigl-to-oise rtio (SN). For rry with specified respose i the directio of the desired sigl, this is chieved by miimizig the me output power of the processor subject to specified costrits. I the bsece of errors, the bem ptter of the optimized rry hs the desired respose i the sigl directio d reduced respose i the directios of uwted iterferece. The smrt te field hs bee very ctive re of reserch for over four decdes. Durig this time, my types of processors for smrt tes hve bee proposed d their performce hs bee studied. Prcticl use of smrt tes ws limited due to excessive mouts of processig power required. This limittio hs ow bee overcome to some extet due to vilbility of powerful computers. Curretly, the use of smrt tes i mobile commuictios to icrese the cpcity of commuictio chels hs reigited reserch d developmet i this very excitig field.. Applictio of Ate rrys to wireless commuictio: Arry processig ivolves mipultio of sigls iduced o vrious te elemets. Its cpbilities of steerig ulls to reduce cochel iterfereces d poitig idepedet bems towrd vrious mobiles, s well s its bility to provide estimtes of directios of rditig sources, mke it ttrctive to mobile commuictios system desiger. Arry processig is expected to ply importt role i fulfillig the icresed demds of vrious mobile commuictios services. This referece provides comprehesive d detiled tretmet of differet bem-formig schemes, dptive lgorithms to djust the required weightig o tes, directio-of-rrivl estimtio methods icludig their performce compriso d effects of errors o the performce of rry system, s well s schemes to llevite them. This referece brigs together lmost ll spects of rry sigl processig. 3. Directio of rrivl lgorithms Directio of rrivl (DOA) is oe of the most importt prmeters tht eeds to be estimted i most pplictios. For rdr, DOA estimtio is the most importt fctor to loclize trgets. For commuictios, DOA estimtio c give sptil diversity to the receiver to eble multi-user scerios. There re lrge umber of lgorithms for DOA estimtio becuse of its importce i rry sigl processig. Clssicl methods of DOA iclude Mximum ikelihood estimtio derived from Miimum vrice distortioless respose lgorithm, Mximum Etropy method of estimtio. Sigl subspce methods re very well kow s DOA estimtio methods with high performce d reltively low computtiol cost. MUSIC (MUltiple Sigl Clssifictio) fll ito this ctegory. Most of these methods tke dvtge of the fct tht there is oly phse differece betwee sesor outputs, whe the sigls re rrowbd. Therefore, the subspce methods work exclusively with rrowbd sigls. 4. esource eservtio Techique: This referece gives compriso betwee trget cell bsed hdover d prepred cell bsed hdover. Provisio of fst d relible hdover d resource reservtio for ew hdover requests is of prime importce i tody s mobile wireless commuictios. A hdover procedure c typicl be divided ito three steps mesuremets, decisio d executio. Bse sttio mkes hdover decisio bsed o the chel mesuremets report from users, d iforms user its trget cell. dover executio is the process mde t the User Equipmet (UE) to All ights eserved 0 IJACET 39

3 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology chge its servig cell to the trget cell. My reserches hve bee focused to improve the hdover performce, icludig sufficiet mesuremets lgorithms, d hdover decisio d executio cosiderig UE s mobility, eighborig cells lod d user service type. I other spect, i order to reduce the hdover executio time d improve the hdover successful probbility, softer hdover, rchitecture for semless hdover d hdover preprtio were studied. Usully, hdover my fil i two cses. Oe is the dmissio cotrol filure i the preferred trget cell, the other is the rdom ccess filure i the trget cell. I order to void hdover filure resulted i by dmissio cotrol filure, hdover preprtio ws itroduced, which mes trget cell performs dmissio cotrol before hdover executio. But dmissio cotrol i preferred trget cell durig hdover preprtio mybe filed too. I this cse, source cell will sed hdover request to other eighborig cell (i.e prepred cell) with the secod strogest sigl stregth d hdover preprtio will be performed t cell to reestblish dio esource Cotrol (C) coectio. I dditio, there my be other resos tht result i hdover filure, e.g. rdio lik filure i source cell, so UE does ot receive hdover commd ; rdio lik filure i trget cell, so UE cot detect the trget cell or hdover complete cot be trsmitted successfully. esource reservtio t the trget cell is lso to be cosidered for hdover filure or dely. So efficiet resource reservtio scheme usig prepred cell cocept for users d employig dptive rry tes t the bsesttio is to be desiged. III. POBEM FOMUATION A. Sigl Model S e e id si id ( ) si () The combitio of ll possible steerig vectors forms mtrix A kow s the rry mifold mtrix[4]. ece, the received sigl vector x(t) of () c be expressed i terms of A s: x ( ) k M i i0 b ( ) ( ) B. Formtio of Arry Correltio Mtrix i () The sptil covrice mtrix of the te rry c be computed s follows. Assume tht b (sigl) d (oise) re ucorrelted, is vector of Gussi white oise smples with zero me. The sptil covrice mtrix is give by ) E[ x x ] E[( Ab )( Ab (3) The sptil covrice mtrix is divide ito sigl d oise subspces d hece we obti A A I (4) ss Fig.. Uiform ier Arry. Cosider uiform lier rry geometry with elemets umbered 0,,..., -. Cosider tht the rry elemets hve hlf--wvelegth spcig betwee them. Becuse the rry elemets re closely spced, we c ssume tht the sigls received by the differet elemets re correlted[3][4]. The Steerig vector is such mesure d for te elemets rry it is give by Where, is All ights eserved 0 IJACET Arry Correltio Mtrix or Sptil Correltio mtrix, A is Arry Mifold ector, hermiti trspose of A, is oise vrice. I. MAXIMUM IKEIOOD METOD The Cpo AOA estimte is kow s Miimum rice Distortioless espose (MD)[5]. It is lso ltertively mximum likelihood estimte of the power rrivig from oe directio while ll other sources re cosidered s iterferece. Thus the gol is to mximize the Sigl to Iterferece tio (SI) while pssig the sigl of iterest udistorted i phse d mplitude. The source correltio mtrix is ssumed to be digol. This ss mximized SI is ccomplished with set of rry weights give by A is 40

4 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology w MD xx ( ) ( ) (5) xx ( ) Where, mtrix xx xx is the iverse of u-weighted rry correltio d ( ) is the steerig vector for gle. The MM pseudo spectrum is give by P MM ( ) ( ) (6) iv Where, ( ) is the hermiti trspose of ( ) d iv is the iverse of Arry Correltio mtrix.. MAXIMUM ENTOPY METOD This method fids power spectrum such tht its Fourier trsform equls the mesured correltio subjected to the costrit tht its etropy is mximized[6]. The solutio to this problem requires ifiite dimesiol serch. The problem hs to be trsformed to fiite dimesiol serch. Oe of the lgorithms proposed by g d McClell hs power spectrum give by PME (7) [ S C C ] S Where, C is colum of - d S is the steerig vector[6]. ( P ME (θ) is bsed o selectig oe of th rry elemets s referece d ttemptig to fid weights to be pplied to the remiig - received sigls to permit their sum with miimum me squre error fit to the referece. Sice there re possible refereces, there re geerlly differet P ME (θ) obtied from the possible colum selectios of -. I. MUSIC METOD MUSIC Method promises to provide ubised estimtes of the umber of sigls, the gles of rrivl d the stregths of the wveforms[7]. E-method mkes the ssumptio tht the oise i ech chel is ucorrelted mkig the oise correltio mtrix digol. The icidet sigls my be correlted cretig o digol sigl correltio mtrix. owever, uder high Sigl correltio the trditiol MUSIC lgorithm breks dow d E Method must be implemeted to correct this problem. Fig. 3. MUSIC System. As show i Fig. 3 the E lgorithm estimtes the covrice mtrix d the performs Eige vector Decompositio to form the subspce. Eige vlues d eigevectors provide useful d importt iformtio bout mtrix. It is possible to determie whether mtrix is positive defiite, ivertible, idicte how sesitive determitio of iverse will be to umericl errors. The Eige vlues of x Arry Correltio mtrix obtied i equtio (3) is foud by solvig the chrcteristic equtio give by I 0 (8) The solutio to equtio (8) gives Eige vlues,...,,. The Eige ector for specific Eige vlue λ is foud by solvig the equtio give by Where (9) is x mtrix comprisig of ukow vribles. Expdig equtio (9) i mtrix ottio, oe c obti 0,0,0,0 0,,, 0,,, (0) Multiplyig the mtrices, set of simulteous equtios s defied i () re obtied 0,0,0,0 0,,, ,,, () Sice there re Ukows we hve simulteous equtios which c be solved to obti,...,,. 4 All ights eserved 0 IJACET

5 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology These vlues form Eige vector mtrix. The Noise subspce is the ormlized to obti better resolutio s compred to few previous DOA lgorithms. The Eige vlues d eigevectors for correltio mtrix is foud. M eigevectors ssocited with the sigls d M eigevectors ssocited with the oise re seprted. The eigevectors ssocited with the smllest Eige vlues re chose to clculte power spectrum. For ucorrelted sigls, the smllest Eige vlues re equl to the vrice of the oise. The ( M) dimesiol subspce sped by the oise eigevectors is give by 4. If hdover fils i trget cell, UE will select suitble cell to perform C coectio reestblishmet, which will ot succeed uless the suitble cell is prepred. ere the more the prepred cells, the higher the coectio successful probbility. 5. elese resources. E e e e... () N 3 e M Where, e i is the i th Eige lue. The oise subspce Eige vectors re orthogol to the rry,,.... steerig vectors t the gles of rrivl M. Becuse of this orthogolity coditio, oe c show tht the Euclide distce d ( ) E E ( ) 0 for ech d every gle of rrivl M.Plcig this distce expressio i the deomitor cretes shrp peks t the gles of rrivl. N N,,.... The MUSIC pseudo spectrum is give by PMUSIC (3) ( ) EN EN ( ) Where, ( ) is steerig vector for gle, E N is mtrix comprisig of oise Eige vectors d i is the i th eige vlue. Fig4. Trget cell bsed hdover. I the bove fig.4 if mobile is to be hdover to y of the 3 trget cells, fixed mout of resources re reserved to service hdover requests, if the user umber exceeds the vilble resource hdover filure occurs which results i hdover dely. So i order to solve this prepred cell bsed hdover techique is developed i which if the hdover fils i the trget cell the hdover request is set to the other prepred cells depedig o the secod lrgest sigl stregth received compred to the stregth of sigl received from the trget cell bsesttio [8][9]. II. ESOUCE ESEATION SCEME A. dover Preprtio Scheme Prepred cell is itroduced to recover the hdover filure. It mes more th oe eighborig cells perform hdover preprtio. The followig steps re followed for hdover:. Upo receivig the mesuremet report, source bsesttio mkes hdover decisio d seds hdover requests to multiple eighborig cells with better chel coditio.. dover preprtio is performed by those eighborig bsesttios. Ad fter tht, hdover request respose will be set to the source bsesttio. 3. Soure bsesttio selects trget cell from ccessible cells d leves others s prepred cells. Fig 5.Prepred cell bsed hdover. I the bove fig.5 two trget cells re cosidered for hdover bsed o the directio of movemet of mobile equipmet. I All ights eserved 0 IJACET 4

6 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology cse of hdover filure i T, hdover is preformed t either P or P prepred cells. Similrly for T cell P d P ct s prepred cells. B. Shrig esource Pool i Prepred Cell It ssumes tht cell # hs received - hdover requests d reserved resource Cho for them. The totl resource of the cell is C, d the preset i-use resource is Cused. The for the th hdover request, the vilble resource C c be clculted by usig C Where, C C used C ho C vilblecpcity C used cpcityiuse C ho hd over cpcity C totl cpcity The hdover cpcity is give by C i ho C ri Where, C is the resource reserved for ith user. ri (4) (5) Appretly, mog the - UEs, for exmple, m UEs wt to tke cell # s trget cell d others wt to tke cell # s prepred cell. owever, i trditiol, cell # will reserve dedicted resource for ech UE. ece the Cho c be geerlized s equtio C ) C (6) ho Where, ( C resource reserved for th user While i the proposl, cell # will ot reserve dedicted resource for UEs tht wt to tke it s prepred cell d provide them resource pool. ece the Cho c be geerlized s m Cho mc C (7) w Where w is shrig fctor which is o less th. The bigger the w, the smller the resource pool. With the Cho i theproposl, C for the th hdover request is icresed gretly. B. Successful dover Probbility Where, P pre P tr t rget probbility Prepred Probbility The trget probbility is give by P tr Where, Ad ( ( P dmi ) )( P rf P dmi isthe dmissio probbility P rf rdom ccess filure probbility P The probbility of the prepred cell is give by pre P dm P N rf 0 p q Where Probbility of UEs filig i rdom ccess. P q ) (9) (0) is the probbility of UE ccepted by the cell i the Cse of UEs selectig the cell s suitble cell fter Filig i the trget cell. P d q re clculted bsed upo by cosiderig probbility of rdom ccess filure s biomil rdom vrible[]. III. SIMUATION ESUTS ere the DOA lgorithms mely; MM, MEM, d ew Eige ector method re simulted usig MATAB. Assumptios. Distce betwee te elemets is to void grtig lobes.. Sigl d Noise is u-correlted. Cse: Widely spced source with less umber of te elemets Tble: Iput to MM, MEM d MUSIC Method Number of rry elemets Number of sources Directios of Sources Amplitude sources 8 [0 0, 50 0 ] [, ]v of dover will ot succeed util rdom ccess succeeds i trget cell or i prepred cell. Successful hdover probbility PO_ succ equls Ptr i trget cell plus Ppre i prepred cell. It c be geerlized s follows: P ho P tr P pre (8) All ights eserved 0 IJACET 43

7 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology Fig. 7. Comprisos of MM, MEM d MUSIC Method for closely spced sources with less te elemets. Give cse whe sources re closely spced d less umber of te elemets re used s show i Fig. 7 it is foud tht Brtlett d MEM perform bdly d ew E method yields better output. Cse3: Widely spced sources with more umber of te elemets Tble3: Iput to MM, MEM d MUSIC Method Number of Number Directios of Amplitude rry elemets of sources Sources sources 50 [0 0, 60 0 ] [, 3 ]v of Fig. 6. Comprisos of MM, MEM d MUSIC Method for widely spced sources with less te elemets. Give cse whe sources re widely prt d less umber of te elemets re used s show i Fig 6 it is foud tht, MM, MEM d E(Eige vector decompositio) method detect directio of sources d ll DOA lgorithms produces best output. Cse: Closely spced sources with less umber of te elemets Tble: Iput to MM, MEM d MUSIC Method Number of rry elemets Number of sources Directios of Sources Amplitude sources 8 [5 0,30 0 ] [, ]v of Fig. 8. Comprisos of MM, MEM d MUSIC Method for widely spced sources with less te elemets. Give cse whe sources re widely prt d more umber of te elemets re used s show i fig 8, it is foud tht performce of MM, MEM d E methods is good. Cse4: Closely spced sources with more umber of te elemets Tble4:Iput to MM, MEM d MUSIC Method Number of rry elemets Number of sources Directios of Sources Amplitude of sources 70 [30 0,33 0 ] [,]v All ights eserved 0 IJACET 44

8 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology Fig. 9. Comprisos of MM, MEM d MUSIC Method for closely spced sources with more te elemets. Give cse whe sources re closely spced d more umber of te elemets re used s show i fig 9, it is foud tht performce of D&S, MEM d E methods is good becuse EM wve strikes more umber of te elemets. Fig. Novel cpcity clcultio for FDMA-TDMA bsed system for cell. From Fig the first br idictes the totl cpcity, the secod idictes the used cpcity for coected users. The third idictes the vilble cpcity for curret hdover users d fourth idictes the vilble cpcity for future hdover requests for trditiol resource lloctio scheme for FDMA-TDMA system. Fig0. Trditiol Cpcity clcultio for FDMA- TDMA bsed system for cell. From Fig 0 the first br idictes the totl user cpcity, the secod idictes the used cpcity for coected users. The third idictes the vilble cpcity for curret hdover users d fourth idictes the vilble cpcity for future hdover requests for trditiol resource lloctio scheme for FDMA-TDMA system bsed o trget cell bsed hdover techique. I this GSM(Globl system for mobile) stdrd is tke s comprtive referece for performce clcultio of system combiig Prepred cell cocept for itercellulr hdover d SDMA to icrese user cpcity by usig sptil diversity. All ights eserved 0 IJACET Fig. Trditiol cpcity clcultio for FDMA-SDMA bsed system for cell. From Fig the first br idictes the totl cpcity, the secod idictes the used cpcity for coected users. The third idictes the vilble cpcity for curret hdover users d fourth idictes the vilble cpcity for future hdover requests for trditiol resource lloctio scheme for FDMA-SDMA system. As compred to FDMA-TDMA cpcity hs icresed by lrge mout for future hdover requests. I FDMA-SDMA bsed system cosidertio is 45

9 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology tke tht differet users t differet gulr loctios use sme frequecy chel [3]. equipmet is clculted for prticulr cell by tkig oly trget cell i the trditiol techique. But i the proposed ovel techique both trditiol d prepred cells re cosidered for hdover process. I trditiol techique oly successful hdover probbility Ptr is clculted, but i ovel techique the sum of Ptr d Ppre is clculted d thus it chieves icrese i successful hdover probbility th the trditiol techique. IX.CONCUSION Fig 3. Novel cpcity clcultio for FDMA-SDMA bsed system for cell. From Fig3 the first br idictes the totl cpcity, the secod idictes the used cpcity for coected users. The third idictes the vilble cpcity for curret hdover users d fourth idictes the vilble cpcity for future hdover requests for ovel resource lloctio scheme for FDMA-SDMA system. As compred to FDMA-TDMA cpcity hs icresed by lrge mout for future hdover requests. The Directio of Arrivl (DOA) block of smrt te systems bsed o clssicl d subspce methods re preseted. The ew MUSIC ector method is compred with existig MEM d MM method. From the simultio results of MATAB it my be cocluded tht whe the sources re widely spced d less umber te elemets re used, performce of MM, MEM d ew MUSIC method re good. Whe the sources re closely spced d less umber of te elemets re used performce of MM d MEM is worst d MUSIC lgorithm is best suited i this cse. Whe the sources re widely spced d more umber of te elemets re used ll lgorithms perform well. Whe the sources re closely spced d more umber of te elemets re used performce of MM, MEM d MUSIC lgorithms re improved. The cpcity grphs lso prove tht the vilble cpcities hve bee sigifictly improved s compred to trditiol scheme. The probbility of successful hdover grph lso shows tht the successful hdover is improved i ovel scheme. This ifers tht prepred cell bsed hdover will chieve better icrese i resource reservtio th trget cell bsed hdover. Ad lso with the Icresed computtiol efficiecy of DSP processors mde to chieve icresed resolutio of DOA estimtio lgorithms like MUSIC th MM d MEM methods, which improved d mde it possible to implemet SDMA(Sptil Dvisio Multiple Access) log with FDMA multiple ccess techique for Wireless mobile commuictios. Fig4: Compriso of trditiol d ovel successful hdover probbility. From the fig 4 oe c ifer tht the proposed method hs better hdover probbility s compred to trditiol scheme. ere successful hdover probbility of user EFEENCES All ights eserved 0 IJACET [] l Chd Godr, Smrt Ates CC press, 004. [].C. Godr, "Applictio of te rrys to mobile commuictios, Prt II: bemformig d directio-of-rrivl cosidertios," Proc. of IEEE, ol. 85, No. 8, pp , 997. [3] E.M.Al-Ardi,.M. Shubir, d M.E. Al-Mull, "Ivestigtio of high-resolutio DOA estimtio lgorithms for optiml performce of smrt te systems," Proc. of 4th IEE It. Cory': 3G Mobile Commuictios (3G'03), odo, UK, 5-7 Jue, 003, pp [4] E.M.Al-Ardi,.M. Shubir, d M. E. Al-Mull, "Computtiolly efficiet DOA estimtio i multipth eviromet usig covrice differecig d itertive sptil smoothig," Proc. of IEEE It. Symp. Circuits & Systems (ISCAS'05), Kobe, Jp, My 3-6, 005, pp [5].W.Che, J.W.Zho, " Widebd MD bemformig for coustic vector sesor lier rry, " Proc. of IEEE dr Sor 46

10 Itertiol Jourl of Advced eserch i Computer Egieerig & Techology Nvig., Jue 004, ol. 5, No. 3, pp [6] E. M. Al-Ardi,. M. Shubir, d M. E. Al-Mull, "Performce evlutio of directio fidig lgorithms for dptive te rrys,"proc. of 0th IEEE It. Coi Electroics, Circuits & Systems (ICECS'03),Shrjh, Uited Arb Emirtes, 4-7 December, 003, ol., pp [7] Spielm. D, Pulrj. A, Kilth. T, "Performce Alysis of the MUSIC Algorithm," Proc. of IEEE Itertiol coferece o ICASSP '86, April 986, pp [8] Migju i, Xiomig She, Che, iroyuki Otsuk, A Novel esource eservtio Scheme for Fst d Successful dover IEEE 009 Mohmmd As, Frcesco Dvide Clbrese, Performce lysis of hdover mesuremet d lyer 3 filterig for UTAN TE, IEEE 8th Itertiol Symposium o Persol, Idoor d Mobile dio Commuictios, 007. [9] S. F. Chie, uiyu iu, Ady. Y. ow, Smrt predictive trigger for effective hdover i wireless etworks, i Proceedig of IEEE Itertiol Coferece o Commuictios (ICC), pp. 75-8, Beijig, My 008. [0] Ki-Dog ee rible-trget dmissio cotrol for o-sttiory hdover trffic i EO stellite etworks, i Proceedig of IEEE ehiculr Techology Coferece (TC), pp. 7-35, J [] Frk Gross, Smrt tes for wireless commuictio," McGrw ill. New York, 005 [] ery Strk, Joh W.Woods, Probbility d dom processes with pplictios to Sigl processig, PEASON,0. [3] l Chd Godr, Applictios of Ate Arrys to Mobile Commuictios, Prt I: Performce Improvemet, Fesibility, d System Cosidertios, POCEEDINGS OF TE IEEE, O. 85, NO. 7, JUY 997. [4] AdresF.Molish, Wireless Commuictios,WIEY,0. rish T.S received his degree i Bchelor of Egieerig from isvesvry techologicl uiversity, Belgum, Krtk, Idi. Curretly he is chievig the Mster of Techology degree i Digitl Commuictio & etworkig from U.B.D.T College of Egg, Dvgere, Krtk, Idi. is res of reserch iterests iclude Wireless Commuictios, Ates d propgtio, Sigl Processig. T.D Shshikl received her degree i Mster of Techology degree i Digitl Commuictio from isvesvry techologicl uiversity, Belgum Idi. Curretly she is workig s Assistt Professor i the deprtmet of Electroics d Commuictio t U.B.D.T College of Egg, Dvgere, Krtk, Idi. er res of reserch d techig iterests iclude Digitl Commuictio systems, Ates d MIMO systems, Wireless Commuictios, hs preseted ppers i my tiol, itertiol cofereces d jourls. All ights eserved 0 IJACET 47