针对UWB_PPM多径信号的加权非相干接收机性能分析

针对UWB_PPM多径信号的加权非相干接收机性能分析 针对 UWB-PPM 多径信号的加权非相干接收机性能分析 吴建军, 梁庆林, 项海格 Cfl?$? fl%?ƒ??,,,,??,fl? 1008713 摘 要:fl? UWB-PPM fi?,?f????$???%????$?fiþ??%??fi?‰??,f‰?? , fl??L????????????$???%$,??,f??,?Ç??:??%þ ?%??%?%?,f????o??$?,????$????????f?$K? 3dB ?L%??% TN914.4 文献标识码A 文章编号1000-436X(2006)10-0001-06 中图分类号::: ?%?%?$~?%?%???}oƒ,Q?Ç??:?þ?%? 关键词:??y:????:????$???:???‰???? Performance analysis of weighted non-coherent receiver for UWB-PPM signal in multipath channels WU Jian-jun, LIANG Qing-lin, XIANG Hai-ge (Satellite and Wireless Communications Lab, Peking University, Beijing 100871, China) Abstract: The BER performance expressions and weighting coefficients of the weighted non-coherent receiver for the UWB-PPM signal were analytically derived. Subsequently, the analytical results were validated via Monte-Carlo simula- tion, and the impacts of the sub-interval width and the timing error were also numerical analyzed. It is illustrated that the weighted receiver is at least 3dB superior to the conventional non-coherent receiver, and is robust to the variations of sub-integration width and the timing error. Key words: UWB; energy detection; weighted non-coherent receiver; optimal and suboptimal weighting ???$$?????, 3 1 引言 ?,,, Rake ? ?,%?$ ?fi??{,??}??{fi?þ?ƒ?IR, impulse %?ƒ??C ?%??$radio? 3%??$L[2]??{fi 3 ??fi$,o,,?{?ƒUWB, ultra-wideband%??yC3?$,h%???% ??????$???%h?%ƒ??y??%???‰{fi?,??%ƒ {fi,? , ‰,,,?%??,??{fi????х??,,‰??,f%~‰??%????%?? 20 Q?% ???$? 50~60 ?fio? ƒ,?y}‰?%?%?,,???pьƒ? ,??$,,,???,,???,?,,,? ofi ?fl?~:$?%ƒ %%,??$???,,,?%??}$??A, ?? ???{,?‰?收稿日期:2005-12-31:修回日期:2006-09-05 基金项目:?С?$????????C2005JL10253?‰? ???,,,? Foundation Item:Fund for Fundamental Military Technology Research (2005JL1025)??,???%?,?$$?%?fi?%???%f%?,,ƒ??%?A% ,,? ? fl??%?,Øfi???%?%???? ? ,,~:@?%$f}??K??{ ?????$o ?~?$??$,?flKh??$??? DS ????%?,?$???%????%% ???????? UWB ?‰[3][4]?,fi:?????Q ?o ?,???:?%?K? ,?%??}?,?Q?? @?[4]$}ƒ????$??? ?%fi??$???%??????o ?? K2.2 接收机模型 ?%?fl? UWB-OOK ,?,?ƒ,?$?? UWB-PPM ??,??????fl?L?%,H 0 T/2 T f f2 2 ?? Z = Z ? Z= r (t )dt ? r (t )dt ? 0 Q?ƒ?????0 1 ?? ?0T / 2 ? f ? ? H1 ?,%???% ??K??,, ?%??????fi?þ‰? (2) ‰$,Z ? Z??$?????ø? ?%??$????? ?%о fi $?fi $?fl ?o$@?A0 1 PPM ,?? UWB-PPM ,??fi?,‰? ??????‡???????%??$‰?(2) ofi????~,,,??????$??? WNC, weighted non-Cf% ?fi%?,,? ?% %coherent receiver3?,??, ????%? H??þ‰??%??fi ?‰????‰?, 0 Tf2 0 (3) Z = ω(t)r (t )dt ? 0 Q???:??%þ?%??%?% H 1 ???,2 系统模型 ?,f??o ω(t ) = rect(t; T/ 2) ? rect(t ? T/ 2; T/ 2) ‰$,f f f $@?ø 2 ;?Pffi?%?,ø 3 ;‰2.1 接收信号模型 ,~ ?PPM $@K?$$???? ?f r ect(t; %?,?%?,?%?,??,??%????????%?W ????$???%?????{fi,Q T ) ? U(t ) ? ? ‰$,?,U(t ? T) U(t),T,f ?,????, W ???%????W UWB %????þ% ?%,?,?%? fi?,Q%$f??%‰????fi?,ø ???хfi?%~???flfi?,? 4 ;?%?%o?$?fi?fl? }R%$??f?Kfi ????‰??%??$????,f??%? ??o?? ???,??%?$?o?‰ 1 ?p(t)$????~K%Q??y?%? N?1? s ?????,‰$%???øK??‰?r(t ) = E h(t ? jT? iT? bδ ? τ ) + ? ? p s f j ƒ%?,P,?fl,,,?????$??%????w(t ) (1) y(t)=x(t)+n(t) ‰?$?,??$?,o E ,,??h(t) UWB fi?,‰ ‰$,%,$?j =?? i =0 p $?P,??? ?Q?y?% p(t)%%?,w(t)%?? ‰ 1 ?$???? ?%?%?,?%??$??????‰ ,, N/2 ??,‰$?ø,T$??%???0f 3 加权非相干接收机 %?%?%?%,j $?ø j ?????, 3.1 接收机结构及性能 ?, {b} , j ,?K??,?$?????????fifi,Ns ? ?ø%?,,Q?,???%?%??,fδ, PPM ø,???? W ??ø%???yy??? ƒ~‰????%,??o?},?%ISI ??,???ƒ?UWB B?10dB y?%,?%??y?C? ?? ???????~??%?,% ????$?% y?3,$%o ?N=1 ,?%?%s???fi???? ?$,?p??%fl?$,??????,,???‰ffi N>1 ?,flK? T?2(T+τ )%o?$,UWBs fi? fpdmax ??ø$ ???‰$ T?τ%y%??%?,?,, ??$?%,%???,‰??%?p % IEEE 802.15.3a ?$%fl?dmax ,?$%,‰% y(t)?s(t)+n(t)? ,f?? 2??ƒ??,%,$ Saleh- σ=NWø??,o0 $???%???~???,%??‡? T ?? ? ?E (a h )µ ?????$?,S ?%??%~?%o{?$z ?????fi?%,??%????? P = Q = Q ? ? e 2TT ??σ N WT (a Ta ) + 2N E (a Ha ) ? z 0 f 0 S ?? ? ??ø?t +T ? i Wk2 ?T T ?? ?? Z??= y(t )dt a h ah $%fl‰‰?%???$?, 0,k ? t? ?i ? = Q = Q ? ? (6) T (4) , k = 1, 2,, KT 2L?? ? a [DC T + 2CH ]a aΣ a T/2+t+T? f k Wk?? 2 ? Z= y (t )dt 1,k ? T /2+t ? f k ? D=WT‰$,?ƒ??,??,%%?—f ??$? ‰$ t%ø k ?Ç??:?%?%%?,f k ?Ç%~T% Wk 2 C=N/E%?P,?fl%??,?ƒ 0S ??%??%??%o?Σ=DC T+2CH?$?,%??%~?$?? ‡, PPM $?,?f?,%?$fl?,???????Ç??:?%?$$L~???fi E=E: ?bS??o??? aQ?,???k ?fi6????%%,C3$,??}K ? a $L~?K?%p??Ç??Z = Z ? Z= a(Z ? (5) Q,???%?,? ?$???%???0 1 k 0,k Z)1,k k =1%??o??%???? ?? [4]??? K @?$????$?%?3.2 最佳加权系数 ?Q,? ?????‰?%?‰,????fi? $???ø???Ç:???????,??? ?%‰?o?ƒfi(6)$%????$??????,a = arg max J (a) ?J (a) / ?a = 0 ???$o?, opt ?Q%,,,?fiL?a ?o%$Ç??:?%??? Q%????????fi,??????????,‰ 1 P? Q(?) fl???%~???f%%??,???e fi?}? ?K ???%?????? $?,??,W (t ) = arect(t ? t; T) $fi?k k Wk k =1 T T T ?????%?%??fi??a Σa ???, J (a) = (ah) / a= β h(7) h a=Σ Σ opt T o??????,???$??%?,,?,?%?ah 1 Σa ,f??%????fi ?1 T T ? ??????????$??%,,,?f‰$,β = (a Σ a)/(a h) %~??}? aopt ??%,?, ω(t ) = W (t ) ? W (t ? T/ 2) ,‰$?$??$%?$yf t +TT /2 +t +T Wkk f k Wk%?$2 ø,%?,~???ø,f%??ø%????? E = x(t )dt ? E?1定义 = S, k S,k ???% a = Σ h fi?? tT /2 +topt f k k ~??%????$?}?,oo??,?????fi?}?f%?? 2 β ?%p??Ç,?L???????x(t )dt ,,??? x(t)?ø k ??$???%??? K ?Ç??:?$%??,=1, T ?? f?%????$?, E= Eoah?S S,k k =1 ???K?, opt T ?1 ?? P h Σ h (8) = Q= Q ) e,opt ( T ? ? aΣa opt opt ? ? K ?}~‰?,%$T/2 = T,?? E??ƒS ?f Wk ??AÇ ,??:???‰k =13.3 准最佳加权系数 ??%?????:?,$?fi????fi??ØÇ??:?%, a , a ,, a ? L{1 2 K ?? %? o?~, ?$???P??,??T ????þ?P,?fl$},??%?fi?}? ,, E = E / E ,?þ??ƒ‡????a ?,ØÇ??:?%?~K???}k S, k S T = 2T / K%??:??%, ???$~k Wk f ???,?~T T ,????$??% } ? ? ? ? ? $ fi,h ? E , E ,L, E{} ??fl?,,,?fi???$??%??%, 1 2 K T H ? diag{h} t ? T ,T ,,T T ? diag{t} ?þL,o{}p$??? 1 2 K T ? a = h ? E , E ,, E L{}1 1 2 K?[6]?????? ??@%,{Ç??:%? ~:?,??%??fi?‰?o??p?(9) ? T 1/ 2 1/ 2 1/ 2 Tfl??,?$‰?? K ?fØÇWk a= h? E, E,L, E?}{ 2 1/ 2 1 2 K ? ?fl?$%,??$???:???????fl‰??fi??????????? ? ????,Z??K??,‰?$o 2 ? ØÇ??:?%'0'?'1'?Q????$?% ?%?%,?%???????,?????,Qх‰????fi?‰?, ?fl???Kfi???o fl‰??fi?‰???%??? $?fi? ??, T T ?? ?? a h hh 1 ?? P = Q = Q (10) ? ? e,a 1T T ?1?? a Σ Σ h h? 1 1 ?? a ? T T ???? h hh a 2 1/ 2 ??? ?= Q = Q P (11) e,a 2T T ????? a Σ Σ h1/ 2 2 2 1/ 2 ???? 1ah ?,,,??????$???fi, ?fl‰? (a) CM1-52 ?fi?%??? ????? fi?%??? 4 性能分析及讨论 ???????p??,?fl%$,%‰ ,f???‰????,????????fi?o ? Monte-Carlo $@? {??fl, ,f?????,Q?~, ??%??? ????fÇ????$:??%?????? 4.1 分析条件设置 ?%?%o ???????(b) CM4-51 ‰ 2 T=10ns þ????$?????? wUWB %?y?%??? ?fi?f% 1ns ‰,y?%?,:,‰%???%?,$,????? ?fl?CM1 52 ?,,,?? ??? %?%ø?‰ 2 $???$,???%??~ CM4 51 ?,,, %?%ø?,Q%???%??,?????????%???$L%? 1ns %%??я???:,‰,,,? ‰ ? 3 ??,??fi?‰?ƒ?,f??? ?%?o??????ƒ? ?K,??y?%?$fi?%??f,????, 114ns ? 360ns PPM ,?f???%??,?fl???????%?? {?‰,??%?? ƒ‰????%f?o??? T????, 230ns ? 722ns?? o??$??f ???$???%? ???ø%y???, P=1×,,????,eW=5.0GHzoflK,??? ?5 ???%?%????, N=1o 10%,}?????$? s ???????,??????????f%????,? ?%??$,K?$???fÇ??:??% TW ?%??????ƒfl?,‰,????,=10ns %,,,??,,? ? 2 ?,‰,,,???? 3.6dB ? 3.3dB ,?fl?$K?? ,,,?f%Ç??:??? K ??, 12 ? ?Lo 36:fl?Ç??:??% T%?%,??W ?‰ 2 CM4-$h???$,,‰,,,?? f 3ns ? 10ns 2 ???%????? 51 %?$ ? ? ??? ? ??? ? %???%??fl:ffl?? 4.4 定时误差的影响 K,?fl 2 ?‰fl $%???;????$,? ????$????%? ?fi?‰? a?,,?fl?fl??fi?‰? a2 1 ???????fi?%??:f????:??A??%??L,~‰?%?% ,??Çfl?, ?%??fi?‰? a1 ??Ç??:? fl??fi?‰? a???? ,?2 ?%?$,???%Ç??:??A?? ???fi?%??ofl ?fio 4.3 子积分区间宽度的影响 T=10ns E/N= 20 ?%???,??,?W b0 Ç??:??%?%%???????dB % 3 ?‰,?fl? ,f,???$????þ???,‰$(a)?(b)?ƒ,‰,,,? CM1-52 ??? 2?% ?? 2 ?Ç??:????A,?ƒ?CM4-51 fl??,o?‰$???$,2 0.5 dB CM4-51 ,‰f?$%??o%%? ??Afl?‰? ?Ç??: 2 ?,‰?? ,?? ,?fl,？?,?%???%%??o???,??%f%??????Q%????$????????f??‰ 4 ??,‰(a)?(b)??‰$??ƒ,,f? ?,,,,? CM1-52 ? CM4-51 fl??,o?‰?5 ? 3 dB ????$???$??%??%%$,???P=1×10%???, 0.5 e???$, ?ƒ?%? $dB????? ,???$ ?%ƒo??Ç??:??%%??$~?%?%?}????????~ ???}:?~ %??,? CM1-52 ,‰f?, 1.0 dB ,f???????{,Ç:???%?fi,?h??? ?f%?T=1ns %??? ,f???%?W ?%??%o(a) CM1-52 (a) CM1-52 (b) CM4-51 ‰ 3 ????$??????Ç:??% T=3, wCM4-51 (b) 10ns %??fl?‰ 4 ?%???????$?????? ?~?$‰%??%,?Ç??:??%?%?? ?ƒ??,$@?%fl? 2 ?,‰?%?? ,,,??,f?$%,3 ???fi?‰?%??? ????,,,,?L,?ƒ‰?,‰????%? ?????o?h?? ?%??h? ??fi,,,?%??o ???f‰????fi?? ,,, signals[A]. Proceedings of IEEE 6th Workshop on Signal Processing 5 结束语 Advances in Wireless Communications[C]. New York, USA, 2005. 158-162. $@fl? UWB-PPM fi?,?? FOERSTER J. Channel Modeling Sub-committee Report (Final) [R]. [5] ?f????$ Technical Report IEEE P802.15-02/368r5-SG3a, 2002. ???%????,‰?f??%???[6] WU J, XIANG H, TIAN Z. Weighted noncoherent receivers for UWB Q?~,‰??$?fi, PPM signals [J]. IEEE Communications Letters, 2006,10(9): 655-657. ?????$???%????fi? f 作者简介:‰?,%$f 2 ???,,,?%‰ ????fi?‰?o吴建军(1968-3,?,ff? $@??????????$,?T,fl?$??Ç?fifl%? ? ?,???$???%??‰???? ?????fi?%$,??,f,,,?????,K???{ƒ? /? ， ?,Q?Ç??:??%þ?%??%?% ?,?? ?,,fl%?,,??y?,?o 参考文献:???????o??$?,$@??%?$?,f梁庆林C1941-? 3,?,?flø}$, [1] WEISENHORN M, HIRT W. Robust noncoherent receiver exploiting ???????f?$K? 3dB ?L%??%fl?$??fifl%?Ç?ƒUWB channel properties[A]. Proceedings of International Workshop ??,,,,?? on Ultra Wideband Systems, Joint with Conference on Ultrawideband ??,?TR?ƒ,QSystems and Technologies, Joint (UWBST & IWUWBS 2004)[C]. ??Ç??:?þ?%??%?%$~/ Kyoto, Japan, 2004.156-160. ? ?‰?}of?%$%?,K???{?,?? ? ，?,,fl%?,,,?‰??oDURISI G, BENEDETTO S. Performance of coherent and noncoherent [2] ????fi??,,,? ‰?,?%?% receivers for UWB communications[A]. Proceedings of IEEE International fi???fh?$??%???oConference on Communications[C]P. aris, France, 2004. 3429-3433. 项海格1941-C 3,?,p???$,SAHIN M E, GUVENC I, ARSLAN H. Optimization of energy de- [3] fl?$??Ç?fifl%?ƒtector receivers for UWB systems[A]. Proceedings of IEEE 61st Ve- ??,,,,??hicular Technology Conference (VTC 2005-Spring)[C]. Stockholm, ??,?TR?Sweden, 2005. 1386-1390. ??,‰ ?{?,[4] TIAN Z, SADLER B M. Weighted energy detection of ultra-wideband ?,Kщ?,???,,fl%?,?o