tailieunhanh - Acoustic Waves From Microdevices to Helioseismology Part 13

Tham khảo tài liệu 'acoustic waves from microdevices to helioseismology part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 468 Acoustic Waves - From Microdevices to Helioseismology Applying circuit theory definitions of y matrix elements are presented 11 e1 2 0 1 V12 T- e2 Appendix. 4 1 V13 e3 1 0 2 0 3 y 3 1 0 2 0 And using trigonometric functions as follows 2 tga- - cot ga sin 2a 11 . .X tga tga- cot ga sin 2a 2 3 cos 2a 1 - tga sin 4a - tga sin 2a tga sin 4a tga sin 2a - cos 2a Appendix. 5 tg 4a The y matrix can be obtained for 2 models as follows - for the crossed-field model 11 - jG0cot g 4a jGo y12 . 0 sin 4a 13 -jG0tga y33 j 2fiCo 4Gotga Appendix. 6 for the in-line field model G I G . 11 -jG0cotga cotg 2a C Go cotga -0- _ . I oCo sin 2a y12 JG0 TG 2127 - cot ga -G - cot g 2a I oco JiaCo tga 13 - jG0--2G----- 1 - 2G- tga oCo s j2aCo y33 J2G. 1 - tga oCo s 2 11 sin 2a 2 G 12 1 G cot g 2a I C0 2 1 1 Appendix. 7 SAW Parameters Analysis and Equivalent Circuit of SAW Device 469 In IDT including N periodic sections the N periodic sections are connected acoustically in cascade and electrically in parallel as Figure . Fig. . IDT including the N periodic sections connected acoustically in cascade and electrically in parallel Because the symmetric properties of the IDT including N section like these of one periodic section and from Figure and Figure the Y matrices of N-section IDT are represented as follows J11 Yn J12 - 1 13 13 13 13 a M Yn . 3 12 13 13 - 3 b corresponds to model corresponds to model Fig. . The Y matrices and the model corresponsive models Since the periodic sections are identical the recursion relation as follows can be obtained e1 m e2 m-1 Appendix. 8 e3 N e3 N-1 e3 N-2 . e3 2 e3 1 Eg i1 m i2 m-1 With m is integer number m 1 2 . N-1 N The total transducer current is the sum of currents flowing into the N sections. I3 i3 1 i3 2 . i3N- 1 i3N y13e11 - y13e21 y33e31 y13e12 - y13e22 y33e32 . y13e1 N-1 y13e2 N-1 y33e3 N-1 y13e1 N y13e2 N y33e3 N