1、 l : 2006-01-19Te: (1971-), o, 2 , =, V,1V Y|) #0Z bcI|:1004-2474(2007) 03-0247-032V oJo :_M林智群1,刘久玲2,何世堂2(1. 2 jv , 2 410128; 2.S S 2 ,100080)K 1: h“ 2V o:_ T ro #Y)Z,4|:_ Tro 2V oJo M, Eb E# LTb LT EB, Z Vb1oM: 2V o;Jo ;:_ ro ms |:TN65 DS M : ASAW Notch Filter Coupledwith Longitudinally Coupled Re
2、sonatorLIN Zh-i qun1, LIU Jiu-ling2, HE Sh-i tang2(1 . College of Science , Hunan Agricultural University , Changsha 410128, China;2. Institute of Acoustics, the Chinese Academy of Sciences, Beijing 100080, China)Abstract: To suppress the / shoulder0 in theadjacent passband of longitudinally coupled
3、 resonator (LCR) filter,we propose to couplethe filter with aSAW notch filter. Results of theoretical simulation and experiment aregiven.The result of experiment is consistent with that of theoretical simulation, which verifies thefeaibility of the method.Key words:surface acoustic wave; notch filte
4、r; longitudinally coupled resonator filter“MY?Z, al8 2V o(SAW) ro m 1b7:_ ro ( LCRF) 1By (2 dB),M z z( 1% 7%),E(50 dB)+7Wb ? WQ Y7 3Y, #Y)BZ, P E z,7Y “ ,K aSb :_ T ro E2 ,| 2V oJo M, 2V oJo Y ,7+ ( LCRFZ)+3 , :_ T ro Y+b1 理论分析1.1 :_ ro Y+m1:_ ro b g Vw:_ gW , i1i2= Y11 Y12Y21 Y22u1u2 ( 1) , Vw Y 4S
5、12= - 2Y12 GinGout(Gin+ Y11 )(Gout+ Y22)- Y12 Y21 ( 2)sV UIL= - 20lg| S12| =20lg (Gin+ Y11)( Gout+ Y22) - Y12Y212Y12 GinGout(3)T Gout ,; Gin ,bm1 1-2 T:_36bYX-LiTaO3 , q352 MHz, ? 28, d45Ks,Q EEH 150; (Al)400 nm,m2 T(3) E1-2 T Y+bm2 1-2 T:_ Y+29 3 2 ;Vol. 29 No.32007 M6PIEZOELECTECTRICS RiE F; Rb1=
6、( RA MZd); Rb2= jXL+ Rb1; Rb3= Rb2 M( Zd2 ); Rb4= jXL+Rb3 ; Rb5= Rb4 MZd ; RA= 1/ Y11- Y12 Y21 / ( 1/ R0+Y22) b T(5) E Y m6 Ubm VA,F Y Jo :_ ro ,V7r4 :_ ro Z)bm6 F Y+3 实验结果 s E,36bYX-LiTaO3 TM L, LT m7a8 U, m7:_ L Y+,m8F L Y+b q Y+ ( 50 8“d/ k,F a bVLT A,m7:_ Y+*Zm8$ / , Y “ hl, (r40 dB, - sBbm7 :_
7、L Y248 2 ;2007 M m8 F L Y4 结束语:_ ro E z+,4| 2V oJo :_M, Jo + h“:_ T ro #Y)Z,V7 :_ ro Eb F ET,i LbTV Jo ,:_ ro Ev ,Zh“b ID:1 MORITA T, WATANABE Y, TANAKA M, et al.Wideband low loss doublemode SAW filtersC. Ar-izona :IEEE Ultras Sym Proc Tucson ,1992:95-104.2 BEAUDIN S, DAM PHOUSSE S, CAM ERON T .Shou
8、lder suppressing technique for dual mode saw re-sonators C . Nevada: IEEE Ultras Sym Proc LakeTahoe, 1999:389-393.3 GOPANI S, HORINE B A. SAW waveguide-coupledresonator notch filter C . Hawaii: IEEE Ultras SymProc Honolulu, 1990:1-5.4 HASHIMOTO K Y. Surface acoustic wave devices intelecommunications
9、 M . Berlin Heidelberg: Springer-Verlag, 2000. Yu 2;v S0 S/“v (0)= E B / 8 S/ ,S Z a S S/ , S , SuEIv oaS S oS = o l c b v16 7, , ,S = 7?bu 2;vS: 2V o/ ;8/ ;0(L/ ; 2;0/ ;. / ;/ , #MEMSNV;8abu 2;v hv S/Tg b h = iFcb1 pn gb lq, ,? cYbT l lY, Vydsg. ch-. _u 2;v: c| ca|f b q72 l Y,T V1) ,|b c = 7(? a a a/ aaZE), h Tk a? q, |5 ci4 -?Vb cT | zrm6rm, h# H|Q I ,Tq !b h7: i 2 2513Qu 2;vI : (023)62919570 I:400060. : (023)62805531,628052840Q: (E-mail) : ydsg sipat. com : http/ www. 3 : 2V oJo :_M249
