Pojc Til D Submid IEEE 80.6 Bodbnd Wilss Accss Woking Goup <hp://i80.og/6> Closd Loop MIMO Codbook fo Mix A nd B STC 005-03-09 Souc(s) R: Mis Wnnsöm, Bnislv Popovic, Huwi Tchnologis, PO Box 54, Kis, Swdn IEEE 80.6-REV Voic: +46-73900803 Fx: +46-84770800 mis.wnnsom@huwi.com Absc Pupos Noic Rls Pn Policy nd Pocdus Fo 3 o 4 BS nnn sysms whn STC mix A nd B wih nnn gouping usd ogh wih closd loop MIMO pcoding h is no opimizd codbook dfind in h sndd. A poposl fo h cosponding codbook is hus psnd in his conibuion ogh wih simulion suls. Adopion of h poposd x ino P80.6 This documn hs bn ppd o ssis IEEE 80.6. I is offd s bsis fo discussion nd is no binding on h conibuing individul(s) o ognizion(s). Th mil in his documn is subjc o chng in fom nd conn f fuh sudy. Th conibuo(s) sv(s) h igh o dd, mnd o wihdw mil conind hin. Th conibuo gns f, ivocbl licns o h IEEE o incopo mil conind in his conibuion, nd ny modificions hof, in h cion of n IEEE Sndds publicion; o copyigh in h IEEE s nm ny IEEE Sndds publicion vn hough i my includ poions of his conibuion; nd h IEEE s sol discion o pmi ohs o poduc in whol o in p h suling IEEE Sndds publicion. Th conibuo lso cknowldgs nd ccps h his conibuion my b md public by IEEE 80.6. Th conibuo is fmili wih h IEEE 80.6 Pn Policy nd Pocdus <hp://i80.og/6/ip/pns/policy.hml>, including h smn "IEEE sndds my includ h known us of pn(s), including pn pplicions, povidd h IEEE civs ssunc fom h pn hold o pplicn wih spc o pns ssnil fo complinc wih boh mndoy nd opionl poions of h sndd." Ely disclosu o h Woking Goup of pn infomion h migh b lvn o h sndd is ssnil o duc h possibiliy fo dlys in h dvlopmn pocss nd incs h liklihood h h df publicion will b ppovd fo publicion. Pls noify h Chi <milo:chi@wilssmn.og> s ly s possibl, in win o lconic fom, if pnd chnology (o chnology und pn pplicion) migh b incopod ino df sndd bing dvlopd wihin h IEEE 80.6 Woking Goup. Th Chi will disclos his noificion vi h IEEE 80.6 wb si <hp://i80.og/6/ip/pns/noics>. 0
Closd Loop MIMO Codbook fo STC Mix A nd B Mis Wnnsöm, Bnislv Popovic Huwi Tchnologis Swdn Inoducion In 80.6/D6 [] h ls wo disinc nsmi sucus fo poviding closd loop MIMO ncoding. Ths h spil muliplxing wih nnn slcion o codbook pcoding, which cn povid spil s up o fou nd h Almoui ncoding ogh wih nnn gouping which cn povid spil of on o wo. Th closd loop MIMO pcoding codbooks in 80.6/D6 [] dsignd nd opimizd fo h us wih spil muliplxing. Howv, closd loop MIMO pcoding cn lso b usd ogh wih Almoui ncoding wih nnn gouping []. In his cs, h pcoding opion is pplid f h nnn gouping opion. Th poblm is h h is no codbook dfind in 80.6/D6 fo his mod of opion lhough h spil muliplxing codbook cn in pincipl b usd. Howv, s is shown in his conibuion, h xising codbooks which opimizd fo spil muliplxing (STC mix C), givs only smll o no gin whn usd ogh wih STC mix A o B plus nnn gouping. This cn b xplind by h fc h h cun codbooks "bmfoming codbooks", which suibl fo spil muliplxing sysms bu do no k ino ccoun h spc-im divsiy sucu of h Almoui ncods in is dsign. In his conibuion w popos codbook, compc in is dscipion nd dsignd o b usd wih 3 o 4 BS nnn sysms whn STC mix A nd B plus nnn gouping is usd. This codbook is opimizd fo his yp of opion nd whn compd using h xising codbook in 80.6/D6 i shows significn gins. Th nw codbook nd is us W popos wo codbooks, on fo h 4 BS nnn sysms nd on fo 3 BS nnn sysms. Hnc, h sm codbook is usd indpndnly if mix A o mix B STC ncods usd. Howv, h MSS slcion cii will dpnd on which STC mix is usd fo h nsmission bu no h h slcion cii no p of h sndd. Sinc h numb of STC oupu sms is qul o h numb of nsmi nnns, h pcoding mics will b squ. Th suggsd pcoding mics digonl nd cn hus b compcly dscibd nd sod in mmoy. Also, h pcoding opion bcoms simpl scl muliplicion p nnn signl. Th opion of h nw codbook is h sm s fo h codbook bsd on spil muliplxing fo closd loop MIMO. Th MSS slcs pfd mix fom h codbook nd signls h cosponding codbook indx o h BS. Th nnn gouping (AG) slcion nd pcoding (PRC) mix slcion my o my no b don joinly, which llows h flxibiliy o hv diffn poing piods fo h AG slcion nd h PRC slcion. Whn boh AG nd PRC slcd in h MIMO Compc DL-MAP IE, i is implicily ssumd h boh BS nd MSS us h codbook poposd in his conibuion.. Codbook fo 4 nnn, STC mix B Th spil fo his ncod is wo nd hnc h wo goups of Almoui spc im ncodd signls will inf wih ch oh in h civ. Th oupu fom h nnn gouping opion is 4 sms nd h 4 nsmi nnns, so ll h lmns in h poposd codbook s 4 by 4 mics. Accoding o [], i is sufficin o consid h following pcoding mix sucu
c jθ 0 0 0 0 c 0 0 () 0 0 c3 0 0 0 0 c4 wh c i i =,,3, 4 l vlud nd θ is phs which is slcd o mk h infnc bwn h wo subspcs cosponding o h wo Almoui ncodd signl goups s smll s possibl. I ws shown in [] h i is sufficin if on of h fou digonl lmns of h pcoding mix is complx vlud, nohing is gind by dding mo complx vlud cofficins. Th lmns c i i =,,3, 4 nd θ in () slcd using 6 bi CQICH. Th vibls c i i =,,3, 4 cn k h vlus, 7 0. 343 o 3 7. 37 nd h phs ngl θ is slcd fom h s 0, ±0 nd ±60. No h hs phss do no smpl h whol 360 ngl spc. Th son is du o h pcding nnn o gouping, which hs ffcivly ducd h usful ngl spc (in oh wods, ngls θ > 90 obsol sinc hy would duc h SNR in h civ nd cn hus b movd, hby incsing h soluion in h usful ng of ngls). No ll possibl combinions of c i i =,,3, 4 cn b usd in h codbook, sinc h ol did pow should b invin o h slcion, hnc c + c + c3 + c4 = 4 mus hold fo ll mics in h codbook. Th poposd codbook cn b sn in dil in Scion 5. A h MSS, h slcion of codbook mix cn b dmind bsd on ny dsid cii such s minimum BER, minimum mn squ o o minimizd coss infnc bwn h wo Almoui ncodd signl goups. Th slcion cn b md joinly wih h nnn gouping slcion o sply, h is, nnn gouping slcion is pfomd fis nd hn h bs possibl pcoding mix is slcd givn h nnn gouping slcion. This llows us of diffn CQICH poing piods fo h pcod nd h nnn gouping, if dsid. Fuhmo, mo dvncd slcion mhods (filing, pdicion ) cn lso b usd o duc h ffcs of fdbck dly.. Codbook fo 4 nnn, STC mix A Fo his mod, w us h sm codbook s in h STC mix B cs in Scion.. Howv, in his mod, h spil is on nd hfo, h is no coss-infnc bwn h wo goups of nnn signls o consid in h civ. Thfo h vlu of h phs ngl θ hs no impc on h pfomnc nd nd no b kn ino ccoun in h slcion cii. Also, h slcion of h pcoding fo nnn nd cn b md indpndnly of h pcoding slcion fo nnn 3 nd 4. To mk h schm mo obus o fdbck dly, h following slcion cii cn b dopd. A h MSS, h indx of h nsmission mix cn b dmind bsd s follows; if Wh i ws ssumd h nnn nd goupd o on Almoui ncodd signl nd 3 nd 4 o h oh. This is of cous dpndn on h slcion in h pcding nnn gouping opion.
h h > T > T h h ohwis choos c choos c choos c = = =, c 3 /7, c /7, c = = = /7 3 /7 wh T> is hshold pm nd h, h h chnnls fom BS nnn nd spcivly (wh hs wo nnns nsmi on Almoui ncodd signl goup. Hnc hy my no cospond o h physicl nnn nd du o h pcding nnn gouping opion). A simil slcion is md fo nnn 3 nd 4 indpndnly of h slcion fo nnn nd. This schm is obus o fdbck dlys sinc whn h opn loop ( =, c ) nsmission is usd. So, in ffc, whn h is lg unciny bou h h c = od lion bwn h wo chnnls in h fuu (i.. h.3 Codbook fo 3 nnn, STC mix B h ), h opn loop schm is slcd. In his mod, h spil is wo, so h is coss-infnc o consid in h civ. Howv, i cn b sn fom h discussion in [] h complx nnn wighs hs no impc on h pfomnc nd w popos h mix sucu c 0 0 c 0 0 0 0 c 3 () wh c i, i =,, 3 l vlud. Th vibls c i i =,, 3 cn k h vlus 7 0. 343, 3 7. 37 o und h consin c + c + c3 = 3, hnc 3 bis ndd o slc pcoding mix fom h codbook. A h MSS, h indx of h nsmission mix cn b dmind bsd on fo xmpl minimizing BER, minimum squ o o mximizing SNR.4 Codbook fo 3 nnn, STC mix A Fo his mod, w us h codbook fo 3 nnn STC mix B in Scion.3. 3 Simulion suls Th codbook pfomnc is vlud by simulions. To mk compisons, w comp wih h cs wihou pcoding (nnn gouping only). W lso comp wih using h xising codbook fo spil muliplxing, o giv infomion bou h bs possibl pfomnc wih h only codbook cunly vilbl in h sndd. Th chnnl modl is ITU pdsin A, 3 km/h, wih nsmi colion of 0. nd civ colion of 0. Th fdbck dly fo boh h nnn gouping fdbck nd h pcoding mix fdbck is fms, i.. 0 ms. Th sysm bndwidh is 0 MHz nd h pck siz is 64 by mppd o singl AMC bnd wih -by-6 block. Th fdbck o pobbiliy is %. Whn h numb of spil sms is wo, h MMSE civ is usd; ohwis h ML civ is usd. 3. 4 nnn mix B Figu shows h pck o compison fo diffn modulion nd cod s. Clly h nw codbook impovs h pfomnc ov using nnn gouping only. Fuhmo, h spil muliplxing codbook in [] shows only smll gin ov nnn gouping. Th pfomnc gin of h nw codbook 3
compd o nnn gouping only 0% PER vis bwn 0.4 db fo QPSK, R _ o 0.7 db fo 64QAM, _. R o E 0 0 A B C D Nw codbook Exising codbook No pcoding (Only AG) k c P 0-4 6 8 0 4 6 8 0 SNR [db] Figu Simulion suls fo 4x MIMO sysm wih nnn gouping only nd wih nnn gouping plus codbook pcoding. Th "Exising codbook" is h 4-by-4 mix codbook in [] using 6 bi fdbck. Th lbls snd fo A: QPSK, R _, B: 6QAM, R _, C: 64QAM, R _ nd finlly D: 64QAM, R _. 3. 4 nnn mix A Th simulion suls fo h 4x MISO sysm wih mix A STC ncod is shown in Figu blow. Th gin of h nw codbook ov no pcoding (nnn gouping only) is bou 0.7 db PER 0% fo h _ nsmissions. 4
R o E 0 0 A C B Nw codbook Exising codbook No pcoding (Only AG) D k c P 0-0 4 6 8 0 4 6 SNR [db] Figu Simulion suls fo 4x MISO sysm wih nnn gouping only nd wih nnn gouping plus codbook pcoding. Th "Exising codbook" is h 4-by-4 mix codbook in [] using 6 bi fdbck. Th lbls snd fo A: QPSK, R _, B: 6QAM, R _, C: 64QAM, R _ nd finlly D: 64QAM, R _. 3.3 3 nnn mix B Fo h 3x MIMO sysm wih STC mix B h pfomnc impovmn fo h poposd codbook ov h spil muliplxing codbook ngs bwn.5 db nd 0.9 db PER 0% fo h picul modulion nd coding sings in Figu 3. 5
R o E 0 0 A B C D Nw codbook Exising codbook No pcoding (Only AG) k c P 0-5 0 5 0 5 30 SNR [db] Figu 3 Simulion suls fo 3x MIMO sysm wih nnn gouping only nd wih nnn gouping plus codbook pcoding. Th "Exising codbook" is h 3-by-3 mix codbook in [] using 3 bi fdbck. Th lbls snd fo A: QPSK, R _, B: 6QAM, R _, C: 64QAM, R _ nd finlly D: 64QAM, R _. 6
3.4 3 nnn mix A Fo h 3x MISO sysm wih STC mix A w s h simulion suls in Figu 4 wh h gin fo h poposd codbook ov h spil muliplxing codbook vis bwn.5 db nd. db PER 0%. B C D Nw codbook Exising codbook No pcoding (Only AG) A A Figu 4 Simulion suls fo 3x MISO sysm wih nnn gouping only nd wih nnn gouping plus codbook pcoding. Th "Exising codbook" is h 3-by-3 mix codbook in [] using 3 bi fdbck. Th lbls snd fo A: QPSK, R _, B: 6QAM, R _, C: 64QAM, R _ nd finlly D: 64QAM, R _. No h h xising codbook shows wos pfomnc hn wihou pcoding ll. 4 Summy Th poposd codbooks dsignd fo 3 nd 4 TX nnn BS using STC mix A nd B givs fo h simuld modulion nd coding sings up o.5 db gin ov nnn gouping (no pcoding) PER 0%. Th codbooks cn b compcly dscibd nd sod sinc h pcoding mics digonl, which lso simpl scl muliplicion in h pcoding opion. 5 Spcific x chngs 7
[Modify h x in h bginning of 8.4.5.4. s suggsd in h following] 8.4.5.4. MIMO ffdbck fo nsmi bmfomingmimo codbook pcoding Codbooks dfind fo h fdbck of MIMO nsmi bmfoming pcodin g wih STC mix A nd B wih nnn gouping o STC mix C. Ths, whos codwod cod wods my b mployd s h bmfoming pcoding mix in MIMO pcoding in 8.4.8.3.6. Th codbook fo 4 nnn nd 3 nnn BS using nnn gouping nd wh n h numb of STC oupu sms quls h numb of BS nsmi nnns consiss of digonl mics. T h digonl lmns lisd in Tbl NNN nd Tbl NN Nb spcivly. An ll oh css, h codbooks lisd in Tbl s 98g o 98d. Th vco codbooks fo x, 3x, nd 4x wih 3 bi fdbck indx lisd in Tbl 99, Tbl 99b, nd Tbl 99c, [End of "Modify h x in h bginning of 8.4.5.4. s suggsd in h following"] [Add h following bls in scion 8.4.5.4. ] Tbl NNN 6 bi cod-book fo 4 TX nnn BS using nnn gouping Indx W W W33 W44 w w 7 3 7 w3 3 7 7 w4 7 3 w5 3 7 w6 3 7 w7 3 7 w8 3 w9 3 w0 7 3 w 3 7 w 3 7 w7 7 w8 3 7 3 w9 jπ / 8 3 7 w0 jπ / 8 3 7 w 7 w 3 b w3 jπ / 8 7 3 w4 jπ / 8 3 7 w5 7 w6 3 7 3 7 7 w7 jπ / 8 w8 jπ / 8 7 3 7 w3 3 7 w4 jπ / 8 w5 jπ / 8 7 3 7 w6 jπ / 8 3 7 7 w9 jπ / 8 3 7 7 w30 7 w3 3 7 /8 jπ 3
w3 jπ / 8 3 7 w57 3 7 w33 jπ / 8 3 7 w34 7 w35 3 7 /8 jπ 3 w36 jπ / 8 7 3 w37 jπ / 8 3 7 w38 7 w39 3 7 /8 jπ 3 7 7 w40 w4 7 3 7 / 3 jπ w58 3 7 w59 3 7 w60 7 w6 3 7 / 3 jπ 3 w6 7 3 w63 3 7 w64 7 jπ / 3 3 7 w4 3 7 7 w43 7 w44 3 7 3 w45 3 7 w46 3 7 w47 7 w48 3 7 3 w49 7 3 w50 3 7 w5 7 jπ / 3 3 7 w5 3 7 jπ / 3 7 w53 w54 7 3 7 w55 3 7 7 w56 7 3
Tbl NNNb Inpion of codwod 0b00-0b00 in Tbl 9 8 in h cs of 3 nnn BS pcoding using nnn gouping Vlu W W W33 0b00 0b0 7 3 7 0b0000 3 7 7 0b000 3 7 0b000 3 7 0b00 7 3 0b000 3 7 0b00 Rsvd 0b00 Rsvd [End of "Add h following bls in scion 8.4.5.4. "] 6 Rfncs [] IEEE P80.6/D6 "Ai infc fo Fixd nd Mobil Bodbnd Wilss Accss Sysms- Amndmn fo Physicl nd Mdium Accss Conol Lys fo Combind Fixd nd Mobil Opions in Licnsd Bnds", 004. [] M.Wnnsöm, B. Popovic, "Closd Loop Pcoding fo STC", IEEE C80.6-04/45. 0