Cognitive pilot channel: A radio enabler for spectrum awareness and optimized radio resource management

ICT-MobileSummi 2009 Con e ence P oceedings Paul Cunningham and Mi iam Cunningham (Eds) IIMC In e na ional In o ma ion Managemen Co po a ion, 2009 ISBN: 978-1-905824-12-0 Cogni i e Pilo Channel: A Radio Enable o Spec um Awa eness and Op imized Radio Resou ce Managemen O iol SALLENT1, Jo di PÉREZ-ROMERO1, Paolo GORIA2, En ico BURACCHINI2, Alessand o TROGOLO2 , Kos as TSAGKARIS3, Panagio is DEMESTICHAS3 1Uni e si a Poli ecnica de Ca alunya (UPC), c/ Jo di Gi ona, 1-3, 08034,Ba celona, Spain, Email: [email p o ec ed], [email p o ec ed] 2Telecom I alia, Via G.Reiss Romoli, 274, I-101248, Tu in, I aly, Email: [email p o ec ed], en ico.bu acchini@ elecomi alia.i , [email p o ec ed] 3Uni e si y o Pi aeus,80 Ka aoli & Dimi iou s .,Pi aeus, 18534, G eece Coun y Tel: +30 210 4142772, Fax: + 30 210 4142744, Email: [email p o ec ed] Abs ac : Today’s wi eless communica ions landscape is cha ac e ized by he coexis ence o a ple ho a o dispa a e adio access echnologies (RATs), which exhibi a ying ea u es in e ms o capaci y and co e age capabili ies, mobili y suppo e c. and also o e a g ea numbe o applica ions and se ices o di e en ypes o de ices. In such a miscellaneous en i onmen , mobile e minals a e p o ided wi h a g ea se o op ions while se ing up he pa ame e s o hei ope a ion including among o he s he RAT, ca ie equency, and mus also ake in o accoun he la es end owa ds a lexible spec um amewo k in he e ogeneous adio access ne wo ks (RANs). As a esul , in o de o implemen he op imal ac ion, a mobile e minal needs o be enabled o acqui e knowledge o i s en i onmen and es ablished policies. Apa om mobilizing a a he ime- and powe -consuming ope a ion such as spec um sensing, he Cogni i e Pilo Channel (CPC) concep has been p oposed as a solu ion o p o iding he e minal wi h he necessa y adio awa eness a a gi en ime and place, in a possible lexible spec um managemen con ex . F amed wi hin he abo e, his pape , de eloped wi hin he E3 p ojec , aims a desc ibing he CPC concep by showcasing i s wo old ole. Fi s , as an enable o he swi ch-on p ocess o assis ing he mobile e minal o camp on o he ne wo k side and second, as an enable o an e icien decen alized and ne wo k-assis ed adio esou ce managemen du ing he on-going communica ion phase. Keywo ds: Radio enable , Cogni i e Pilo Channel, Spec um Awa eness, Decen alized adio esou ce managemen 1. In oduc ion Nowadays wi eless scena ios a e cha ac e ized by he coexis ence o a a ie y o wi eless access echnologies, wi h di e en p o ocol s acks and suppo ing a numbe o applica ions and se ices wi h di e en Quali y o Se ice (QoS) demands o be p o ided o e minals wi h di e en deg ees o mul i-mode capabili ies o access he a ailable ne wo ks. In p inciple, each mobile and wi eless Radio Access Ne wo k (RAN) di e s om he o he s by he speci ic ai in e ace echnology, suppo ed se ices, bi a e capabili ies, co e age, mobili y suppo , e c. On one side, he a ie y o RANs and QoS le els o he se ices p o ided o e a g ea oppo uni y o he use s, who ha e mo e op ions o be e i hei expec a ions and Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 1 o 9 cons ain s. On he o he side, he he e ogeneous cha ac e is ics o e ed by hese ne wo ks make i possible o exploi he unking gain esul ing om he join conside a ion o all he ne wo ks as a whole. As a esul , he addi ional dimensions in oduced by he mul iplici y o a ailable Radio Access Technologies (RATs) p o ide u he lexibili y in he way ha adio esou ces can be managed and, consequen ly, o e all imp o emen s may ollow wi h espec o he pe o mances o he s and-alone sys ems. This challenge calls o he in oduc ion o new Radio Resou ce Managemen (RRM) algo i hms ope a ing om a join pe spec i e ha conside he o e all amoun o esou ces o e ed by he a ailable RANs. In his he e ogeneous wi eless ne wo ks con ex , he end owa ds mo e lexible spec um managemen mechanisms is being in es iga ed. Spec um e a ming, which allows a speci ied equency band becoming a ailable o a di e en kind o usage o echnology (e.g. e a ming o GSM spec um o UMTS/HSxPA), can be seen as he simples use case o lexible spec um managemen . Spec um sha ing be ween sma adio echnologies, by e.g. allowing unlicensed adios o ope a e in he TV b oadcas bands i no ha m ul in e e ence is caused o incumben se ices, is a mo e ad anced o m o lexible spec um managemen . Conside ing a lexible spec um managemen amewo k in he e ogeneous RANs scena ios, spec um awa eness a ises as a basic challenge, whe e a numbe o anscei e s wi h lexible ime- a ying assignmen o ope a ing equency and/o RAT a e deployed. Spec um awa eness om he mobile’s pe spec i e e e s o he mechanisms allowing he e minal o be awa e o he communica ion means a ailable a a gi en ime and place. In his espec , in o de o ge knowledge o i s adio en i onmen , he mobile e minal may sense some pa s o he spec um, bu his may esul in a e y ime- and powe -consuming ope a ion i he spec um bands o be sensed a e oo la ge. As an al e na i e, ollowing a simila app oach o he Spec um In o ma ion Channel in [1] and he Common Spec um Coo dina ion Channel (CSCC) in [2], he Cogni i e Pilo Channel (CPC) concep was concei ed as a solu ion o con eying he necessa y in o ma ion om he ne wo k side o le he e minal know e.g. he a ailable equency bands, RATs, ope a o s, e c. a a gi en ime and place [3][4][5]. The concep o he CPC is ela ed o a speci ic phase o he cogni ion cycle [6], consis ing in obse ing he en i onmen . T adi ionally, adio esou ce managemen has been mainly cen alized, based on he p esump ion ha a cen al ne wo k node may ha e a mo e comple e pic u e o he adio access s a us han a pa icula node, so ha decisions can be made wi h mo e inpu s. Howe e , a cen alized implemen a ion could ha e some d awbacks in e ms o inc eased signalling load o ans e delay o he adio esou ce managemen algo i hm’s inpu s o he cen al node. This p e en s an e icien implemen a ion o sho - e m unc ions such as packe scheduling and explains why wi eless cellula echnology e olu ion (e.g. HSDPA) exhibi s he end owa ds implemen ing such unc ions on he adio access ne wo k edge nodes (e.g. base s a ions). Beyond ha , a end owa ds decen alized adio esou ce managemen unc ions in he mobile de ices is cu en ly unde in es iga ion. This app oach has been claimed o be ine icien in he pas because o he limi ed in o ma ion a ailable a he mobile de ice side. Ne e heless, his could be o e come i he ne wo k would be able o p o ide guidelines and policies o he mobile de ice d i ing i s ac ions, while s ill keeping he con ol o he whole ope a ion. In his way, while a mobile-assis ed cen alized decision making p ocess equi es he inpu s om many mobile de ices o a single node, he ne wo k-assis ed decen alized decision making p ocess equi es he inpu om a single node o he mobile de ices, which could be mo e e icien om a signalling poin o iew. The CPC could, he e o e, enable such a ne wo k-assis ed decen alized adio esou ce managemen . This pape p esen s esul s ob ained in he amewo k o he E3 (End- o-End E iciency) p ojec , and in ends o de elop he CPC concep in wo di e en and complemen a y Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 2 o 9 missions. Fi s ly, as an enable o he swi ch-on p ocess ha allows he mobile e minal o ge in ouch wi h he ne wo k side. Secondly, as an enable o an e icien decen alized managemen along he on-going communica ion phase. Acco dingly, he es o he pape is o ganized as ollows. Sec ion 2 desc ibes he ision o a CPC as an enable o he swi ch- on p ocess. The ole o CPC in acili a ing he adio esou ce managemen p ocess, bo h a e camping on and while in ope a ion, is desc ibed in Sec ion 3. Finally conclusions a e summa ized in Sec ion 4. 2. CPC as enable o swi ch-on Le us conside he illus a i e scena io depic ed in Figu e 1, whe e a numbe o ansmi e s, wi h possibly ime- a ying assignmen o RATs and ope a ing equencies, a e deployed. Fu he mo e, in i s mo e gene al iew, a s and-alone CPC ansmi e sepa a ed om he es o ansmi e s in he scena io is deployed. The CPC ansmi e , which is physically ealized on a gi en RAT, ope a ing equency and associa ed bandwid h, is in cha ge o con ey spec um awa eness in o ma ion ela ed o i s co e age a ea. [RAT 2 ( ), 2 ( )] ?? [RAT 1 ( ), 1 ( )] [RAT 3 ( ), 3 ( )] [RAT, , BW] CPC TRx Figu e 1: Illus a i e scena io. 2.1 – CPC design and deploymen The di e en aspec s o be conside ed when mo ing om CPC concep o implemen a ion, ega ding he adio pa , can be iden i ied as: • CPC physical and link laye speci ica ion. This includes e.g. he de ini ion o he app op ia e RAT o ca y CPC in o ma ion, ei he a new one o he adap a ion o a legacy one, he equi ed bandwid h o ansmi he in o ma ion o be con eyed and conside a ions on he ope a ing equency. • CPC deploymen . This includes he de ini ion o he numbe o CPC anscei e s (TRx) wi h hei co esponding con igu a ion (e.g. powe le els, e c.) necessa y o p o ide he CPC in o ma ion o he mobile e minals on a ce ain geog aphical egion. I is wo h no ing ha , al hough business model conside a ions a e ou o he scope o his pape , he pe spec i e p o ided he e is gene ic enough o be applied o di e en business models ega ding he CPC ope a ion and exploi a ion (e.g. CPC can be deployed by a CPC-ope a o wi h i s own deployed in as uc u e o con ey in o ma ion om di e en access p o ide s; CPC can be ope a ed by a legacy cellula ope a o who exploi s al eady exis ing si es o con ey in o ma ion o an associa ion o ope a o s; e c.). As o he RAT used o CPC, in he swi ch-on con ex he CPC in o ma ion needs o be con eyed using a CPC-speci ic adio access echnology, in p inciple sepa a e om ha used o use da a ansmission. This app oach is commonly named "Ou -band CPC" (see Figu e 2), opposing o he "In-band CPC", whe e he CPC in o ma ion is con eyed using logical channels o he same adio access echnologies ha a e used o he use da a ansmission, and ha is mo e sui able o op imized Radio Resou ce Managemen ope a ions (see sec ion 3). Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 3 o 9 MHz RAT2RAT2 RAT1 RAT1 CC PP CC Ou Ou - -Band Band CPC CPC Te minal Te minal CPC CPC In as uc u e In as uc u e CPC In o Physical Aspec s 2.2 – A easible CPC solu ion Figu e 2: "Ou -Band CPC" app oach As o he CPC ope a ing equency, a numbe o al e na i es can be en isaged. Some possibili ies a e: • I is ixed and ha monized a global/ egional basis, conso ium o access p o ide s basis o only a in e nal le el wi hin a gi en access p o ide domain. • I is nei he ha monized no ixed (i.e. CPC ope a ing equency may change). No e ha in his case he CPC does no suppo he swi ch on use case (i.e. swi ch on elies on scanning). As o he in o ma ion deli e y mode, wo main op ions a e iden i ied [5]: • B oadcas CPC. This s a egy only uses a downlink b oadcas channel, whe e he in o ma ion is pe iodically and con inuously ansmi ed. • On-demand CPC. In his case, he in o ma ion is ansmi ed only when needed and eques ed by a e minal. The e o e, he on-demand CPC equi es bo h he uplink and downlink componen s. As o he in o ma ion o be con eyed by he CPC, he amoun o in o ma ion will depend on he complexi y o he scena io (on he basis o he deploymen o a ailable RATs in he conside ed a ea) wi hin he CPC ansmi e co e age ange. As a consequence o he way o con ey he in o ma ion, he equi ed bandwid h could be de e mined. A his s age, i is wo h ema king ha knowing he posi ion o he mobile e minal is no a s ic equi emen o he CPC ope a ion bu a capabili y ha enables highe e iciency in gaining spec um awa eness: • In he e en ha posi ioning is no a ailable, as long as he mobile e minal is able o de ec ( o he B oadcas CPC deli e y mode) o con ac ( o he On-demand CPC deli e y mode) he CPC anscei e , he in o ma ion abou he di e en egions in ha a ea a e a ailable. • In he e en ha posi ioning is a ailable, a subse o he in o ma ion o RATs and equencies a he ac ual posi ion could be iden i ied. The mobile e minal could hen y o connec using ha in o ma ion. Fo bo h cases abo e, in he wo s case he mobile e minal has o make a scanning o e he possibili ies indica ed by CPC o ind ou wha RATs and equencies a e a ailable a i s ac ual posi ion. In he ollowing, a possible Ou -band CPC solu ion is p esen ed, acing he di e en aspec s ela ed o he implemen a ion o he CPC o he swi ch-on case. As o he RAT o be used, he solu ion assumes o e-use he al eady exis ing RATs, conside ing he GSM sys em as bea e . The app oach is based on he ollowing poin s, aking in o accoun he a chi ec u e and main ea u e o GSM sys em: Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 4 o 9 • he L1-L2 a e en i ely GSM-based, hus no equi ing any modi ica ion • he CPC messages a e RR-laye signalling, concep ually analogous o he Sys em In o ma ion messages • he CPC messages a e ansmi ed o e he BCH. The p esen solu ion assumes o dedica e a single GSM ca ie equency o he CPC, possibly loca ed in a band ha monized, and no necessa ily inside he band ypically assigned o GSM. The e o e, he bandwid h equi emen is abou 200 kHz plus gua d bands. Since he GSM sys em is TDMA/FDMA based and o each ca ie 8 ime-slo s a e a ailable, each one wi h a minimum bi - a e o 9.6 kbps using he lowes GSM coding (highe bi - a e pe ime-slo could be a ailable using newe coding schemes, such as (E)GPRS encoding), in heo y one GSM ca ie could o e a minimum bi - a e o 8x9.6 kbps = 76.8 kbps. As o he in o ma ion deli e y mode, he B oadcas CPC app oach is conside ed, equi ing only a downlink channel and hus simpli ying he solu ion and he deploymen . On his basis, a speci ic RR-laye signaling message is con inuously epea ed o e he BCH channel, ins ead o he Sys em In o ma ion messages. The s uc u e o he speci ic RR-laye CPC message is epo ed in Figu e 3. OPERATOR_INFO RAT_TYPE = GSM, UMTS, WiMAX, LTE… Figu e 3: CPC B oadcas message s uc u e. The ollowing ields a e conside ed in he CPC b oadcas message s uc u e: • Ope a o in o ma ion: ope a o iden i ie . This in o ma ion is epea ed o each Ope a o o be ad e ised by he CPC. • RAT lis : o each ope a o , p o ide in o ma ion on a ailable RATs. This in o ma ion is epea ed o each RAT o i- h Ope a o . o RAT ype: could be “GSM”, “UMTS”, “CDMA2000”, “WiMAX”, “LTE”… o Co e age ex ension: could be GLOBAL (i.e. whe e e he CPC is ecei ed) o LOCAL (i.e. in an a ea smalle han CPC co e age) o Co e age a ea: o be p o ided in case o LOCAL co e age (e.g. e e ence geog aphical poin ). o F equency in o ma ion: p o ide he lis o equencies used by he RAT. 2.2.1 – Assessmen o p oposed CPC solu ion In o de o e i y i he p oposed solu ion is sel -consis en and he equi ed bandwid h is su icien o he bi - a e needs o he CPC message s uc u e, in he ollowings a p elimina y analy ical e alua ion is p esen ed. Simila assump ions al eady conside ed in he dimensioning exe cise o p e ious CPC b oadcas solu ion ha e been used [5]. The scena io conside ed in he e alua ion is he one de ined in [5] as he uppe bound COVERAGE_EXTENSION = LOCAL/GLOBAL RAT_LIST COVERAGE_AREA (op ional) FREQ_LIST Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 5 o 9 o p ac ical deploymen s, whe e 5 ope a o s a e a ailable, each one wi h 5 di e en RATs, each RAT wi h 10 ad e ised equencies: • NOP = 5 (i.e. numbe o ope a o s) • NRAT = 5 (i.e. numbe o RATs o each ope a o ) • N eq = 10 (i.e. numbe o ad e ised equencies o each RAT o each ope a o ) The CPC in o ma ion o be p o ided is supposed o be bi -encoded using he same app oach o [5]: • Ope a o in o ma ion BOP: 20 bi s (co esponding o OPERATOR_INFO ield in Figu e 3) • RAT in o ma ion BRAT: 4 bi s (co esponding o RAT_TYPE ield in Figu e 3) • Co e age ex ension B COV: 1 bi , 0 = GLOBAL and 1 = LOCAL (co esponding o COVERAGE_EXTENSION ield in Figu e 3) • Geog aphical coo dina es B GEO: 41 bi s (co esponding o CENTER_LAT and CENTER_LONG ields in Figu e 3) • Co e age a ea B adius: 12 bi s • F equency in o ma ion B eq: 16 bi s (co esponding o each i em o FREQ_LIST ield in Figu e 3) Addi ional assump ions compa ed o [5] ha e been also conside ed: • CPC in as uc u e is based on a cellula app oach: in p inciple, in each cell a di e en CPC con en is b oadcas • P elimina y e alua ions a e on a pe -cell basis • Co e age ex ensions o each RAT a e supposed o be LOCAL (i.e. no GLOBAL co e age) • Each RAT o each Ope a o is supposed o be a ailable only in one local a ea in he ecep ion a ea o he b oadcas CPC message On his basis, he numbe o equi ed bi s o be ansmi ed by he CPC o each cell a e: ( ) ( ) ( ) ( ) eqFREQ adiusGEOCOVRATRATOPOPTOT BN B B B BN BNB ⋅ + + + + ⋅ + ⋅ = In he conside ed example: BTOT = 5 ⋅ (20 + (5 ⋅ (4 + 1 + 41 + 12 + (10 ⋅ 16) ) ) ) = 5550 bi s Assuming ha each use should be able o gain knowledge o b oadcas in o ma ion in maximum TDelay = 0.5 seconds, he ne bi - a e ha should be a ailable o he CPC is: 5550 11.1 0.5 TOT b Delay B R kbps T === As a conclusion, he assessmen pe o med on he p oposed app oach o CPC b oadcas message ope a ions esul ed in a ela i ely low bi - a e equi emen s in he conside ed scena io. In pa icula , wi h he p oposed app oach he equi ed bi - a e is e y low compa ed o he esul s ob ained o p e ious CPC b oadcas app oaches [5] and i can i well wi h he assump ion o using GSM as bea e . The eason o his lowe bi a e equi emen in he solu ion p oposed he e wi h espec o [5] elays on he way how he in o ma ion signalled by CPC is ansmi ed. In pa icula , while in [5] he scena io is di ided in o homogeneous a eas (deno ed as meshes) and o each mesh he combina ion o RATs and equencies a ailable is explici ly ansmi ed, in he p oposal he e i is no needed o conside he meshes. Ins ead, he in o ma ion ansmi ed includes he co e age ex ension o each RAT, which allows he e minal o de e mine whe he i is in he co e age a ea o a gi en RAT o no . Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 6 o 9 3. CPC as enable o decen alised esou ce selec ion op imiza ion As desc ibed in he p e ious sec ion, in bo h a quali a i e and quan i a i e way, he CPC can e icien ly play he ole o assis ing he swi ch-on p ocess a he mobile e minal. In addi ion, a e swi ching on and while he mobile e minal is in an ope a ional s a e, he CPC could also be used o p o ide an op imized, decen alized adio esou ce managemen ope a ion. This sec ion aims a p o iding such a ision o he CPC. T adi ionally, adio esou ce managemen has been mainly cen alized, based on he ac ha a cen al ne wo k node has a mo e comple e pic u e o he adio access s a us han a pa icula node, so ha decisions can be made wi h mo e inpu s. Ne e heless, newly appea ed ac o s like he in oduc ion o no el se ices, equen ly changing en i onmen subjec o use s’ a ic o mobili y luc ua ions, and also space- ime a ying spec um and ca ie usage ende ope a o s’ legacy adio esou ce managemen unc ionali y no always able o ensu e bes o e ed connec i i y and se ice p o ision. In such si ua ions, he use o a cen alized manage would impose la ge communica ion signalling o e head due o as con ex changes. On he con a y, he complexi y can be elaxed by mo ing pa o he adio esou ce managemen unc ionali y in o mo e decen alized solu ions. CPC appea s as an appealing possible u u e solu ion o enabling such a ne wo k-assis ed decen alized adio esou ce managemen . As o he RAT used o CPC in case o adio esou ce managemen ope a ions, he "In- band CPC" app oach seems o be he mos con enien (see Figu e 4), con eying CPC in o ma ion using logical channels o he same adio access echnologies ha a e used o he use da a ansmission, and allowing o bea in o ma ion o bo h uplink and downlink. Time In In- -Band Band CPC CPC Te minalTe minal RATx RATx In as uc u e In as uc u e CPC In o Logical mapping o e RATx RATxRATx da ada a RATx RATx da a da a RATx RATx da a da a RATx RATx da a da a CPC CPC da a da a CPC CPC da a da a CPC CPC da a da a Figu e 4 : "In-Band CPC" app oach Indeed, in his case, wo mains eam ca ego ies a e iden i ied o bo h e e se and o wa d links, namely: con ex in o ma ion and policies. • Con ex in o ma ion: Con ex in o ma ion can ha e ei he he ne wo k o he mobile e minal as i s sou ce. In he o me case, he mobile e minal collec s om i s ne wo k con ex in o ma ion such as adio esou ce op imiza ion objec i es, ne wo k adio capabili ies, ne wo k measu emen s e c. In he la e case, he mobile e minal may send con ex in o ma ion o he ne wo k like de ice capabili ies, use p e e ences, equi ed applica ions and QoS le els, locally conduc ed measu emen s, geo-loca ion in o ma ion e c. Fu he mo e, in his case an ins ance o he CPC mus be also p esen in he uplink. • Policies: An e icien way o an ope a o o allow a decen alized ype o adio esou ce managemen , while keeping a he same ime he con ol o i s ne wo k’s mobile e minals could be consis ing in mobilizing policies. Policies a e de i ed in he ne wo k1 side and sen o he e minal ia CPC o se e as di ec i es ha mus be aken in o accoun du ing each indi idual e minal’s adio esou ce usage op imiza ion p ocess. In o de no o con use his ype o policies wi h o he ypes like high le el 1 Mo e p ecisely, by he special managemen so wa e wi hin he ne wo k side Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 7 o 9 ules pe inen o ope a o s and/o spec um egula o gene al goals and policies, i is e e ed o as Radio Resou ce Sec ion policies (RRS policies) The e minal2, d i en by hose RRS policies oge he wi h ne wo k con ex in o ma ion and o he ypes o policies as s a ed abo e, as well as p o ile in o ma ion being kep in he e minal and co esponding o e minal capabili ies and use p e e ences, can implemen he ac ion(s) o he op imiza ion o i s ope a ion e.g. o he ( e-)con igu a ion o i s ope a ing pa ame e s like RAT, equency, modula ion ype e c. Such a ype o decen alized adio esou ce managemen and op imiza ion is a eally challenging and complex p oblem. While solu ions based on p op ie a y p o ocols migh empo a ily sol e he p oblem, his could be done o a small se o e minals and also would complica e he asks o lea ning and using di e en managemen sys ems and managemen p o ocols o each di e en e minal ype. The e o e, he need o a common, s anda dized in e ace appea s o be o high signi icance o ge ing o e hose hind ances. CPC could play a pi o al ole o his in e ace. I should also be no ed ha such app oaches ha use ei he policy based e icien , decen alized managemen o adio enable s simila o CPC, o bo h, ha e been unde s udy by wo king g oups wi hin majo s anda diza ion bodies such as IEEE [6]. 4. Conclusions This pape has p esen ed he de elopmen o he CPC concep o he e ogeneous wi eless ne wo k scena ios wi h lexible spec um capabili ies. In his con ex , CPC can add ess wo di e en and complemen a y missions. Fi s ly, as an enable o he swi ch-on p ocess ha allows he mobile e minal o ge in ouch wi h he ne wo k side. In his espec , his pape has de ailed a easible CPC solu ion based on a b oadcas app oach, ob aining ha he equi ed bi - a e is e y low (11 kbps in he conside ed example) and can i well wi h he assump ion o using e.g. GSM as bea e . Secondly, CPC can ac as an enable o an e icien decen alized managemen along he on-going communica ion phase. In his espec , his pape has p esen ed he ca ego isa ion o he in o ma ion ha could be ansmi ed. Fu u e esea ch on CPC equi es he analysis o he di e en al e na i es men ioned in a ious scena ios wi h espec o he CPC ope a ing equency, CPC deploymen , CPC deli e y, e c. Simila ly, o he on-going phase u u e esea ch in ol es he de elopmen o he app op ia e decen alised RRM s a egies. Acknowledgemen s This wo k was pe o med in p ojec E3 which has ecei ed esea ch unding om he Communi y's Se en h F amewo k p og am. This pape e lec s only he au ho s' iews and he Communi y is no liable o any use ha may be made o he in o ma ion con ained he ein. The con ibu ions o colleagues om E3 conso ium a e he eby acknowledged. Re e ences [1] M. Buddhiko , P. Kolodzy, S. Mille , K. Ryan, J. E ans “ DIMSUMNe : New Di ec ions in Wi eless Ne wo king Using Coo dina ed Dynamic Spec um Access”, IEEE In . Symp, on a Wo ld o Wi eless, Mobile and Mul imedia Ne wo ks (IEEE WoWMoM), Tao mina/Gia dini Naxos, I aly, June, 2005. [2] D. Raychaudhu i, X. Jing “A Spec um E ique e P o ocol o E icien Coo dina ion o Radio De ices in Unlicensed Bands”, 14 h IEEE 2003 In e na ional Symposium on Pe sona1,lndoo and Mobile Radio Communica ion P oceedings (PIMRC), Beijing, Sep embe , 2003. [3] P. Houzé, S. Ben Jemaa, P. Co die “Common Pilo Channel o Ne wo k Selec ion”, IEEE VTC in Sp ing Con e ence, Melbou ne, May, 2006. [4] P. Co die e al., “E2R Cogni i e Pilo Channel concep ”, IST Summi , Mykonos, June, 2006. 2 Mo e p ecisely, he special managemen so wa e wi hin he e minal Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 8 o 9 [5] J. Pé ez-Rome o, O. Sallen , R. Agus í, L. Giupponi, “A No el On-Demand Cogni i e Pilo Channel enabling Dynamic Spec um Alloca ion”, DySPAN ‘07, Dublin, Ap il, 2007. [6] S. Haykin, “Cogni i e adio: b ain-empowe ed wi eless communica ions”, IEEE Jou nal on Selec ed A eas In Communica ions, Vol. 23, No. 2, pp. 201-220, Feb. 2005 [7] IEEE S d P1900.4/D2.0, IEEE D a S anda d o A chi ec u al Building Blocks Enabling Ne wo k- De ice Dis ibu ed Decision Making o Op imized Radio Resou ce Usage in He e ogeneous Wi eless Access Ne wo ks, No embe 2008 Copy igh © 2009 The au ho s www.ICT-MobileSummi .eu/2009 Page 9 o 9