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View U.S. Patent No. 10765477 in PDF I 1111111111111111 1111111111 111111111111111 IIIII IIIII IIIII IIIIII IIII IIII IIII USO 107 654 77B2 c12) United States Patent (IO) Patent No.: US 10,765,477 B2 Behdad et al. (45) Date of Patent: Sep.8,2020 (54) MICROWAVE ABLATION ANTENNA (56) References Cited SYSTEM U.S. PATENT DOCUMENTS (71) Applicant: Wisconsin Alumni Research 5,246,438 A * 9/1993 Langberg . A61B 18/08 Foundation, Madison, WI (US) 600/374 5,300,099 A 4/1994 Rudie (72) Inventors: Nader Behdad, Madison, WI (US); (Continued) Susan C. Hagness, Madison, WI (US); Hung Thanh Luyen, Madison, WI FOREIGN PATENT DOCUMENTS (US) JP 2004-311334 11/2004 (73) Assignee: Wisconsin Alumni Research JP 2008-142467 6/2008 Foundation, Madison, WI (US) OTHER PUBLICATIONS ( *) Notice: Subject to any disclaimer, the term ofthis J Reinholm, The Characteristic Impedance of Coaxial Cables. Jun. patent is extended or adjusted under 35 14, 2012. Electronics-lab.com, accessed Sep. 18, 2015. http://www. U.S.C. 154(b) by 98 days. electronics-lab .c om/the-characteristic-impedance-of-coaxial­ cables/. * (21) Appl. No.: 14/202,786 (Continued) (22) Filed: Mar. 10, 2014 Primary Examiner - Linda C Dvorak Assistant Examiner - Bo Ouyang (65) Prior Publication Data (74) Attorney, Agent, or Firm - Bell & Manning, LLC US 2015/0250540 Al Sep. 10, 2015 (57) ABSTRACT An antenna system is provided. The antenna system includes (51) Int. Cl. a coaxial cable, an antenna, and an impedance matching A61B 18118 (2006.01) structure. The coaxial cable includes a center conductor HOlQ 9/42 (2006.01) extending a length of the coaxial cable, a dielectric material A61B 18/00 (2006.01) surrounding the center conductor along the length of the (52) U.S. Cl. coaxial cable, and a conductive shield surrounding the CPC ........... A61B 1811815 (2013.01); HOlQ 9/42 dielectric material along the length of the coaxial cable. The (2013.01); A61B 2018/00529 (2013.01); A61B antenna includes a conductor having an electrical length of 2018/00577 (2013.01); A61B 2018/1846 half a wavelength at a selected operating frequency. The (2013.01); A61B 2018/1853 (2013.01); A61B impedance matching structure includes a second center 2018/1892 (2013.01) conductor mounted between an end of the center conductor ( 58) Field of Classification Search of the coaxial cable and a feed end of the antenna. The CPC .......... A61B 18/1815; A61B 2018/183; A61B impedance matching structure is configured to match an 2018/1823; A61B 2018/1853; A61B impedance of the coaxial cable to an impedance of the 2018/1876 antenna. See application file for complete search history. 20 Claims, 16 Drawing Sheets 100a 206 2 4 \ 104a \ I 200 202 I 220 I 222 106a 226 228 US 10,765,477 B2 Page 2 (56) References Cited 2010/0168727 Al* 7/2010 Hancock. A61B 18/18 606/33 U.S. PATENT DOCUMENTS 2010/0185192 Al* 7/2010 Muller A61B 18/18 606/33 5,683,382 A 11/1997 Lenihan 2010/0217252 Al 8/2010 Rossetto et al. 6,051,018 A 4/2000 Larsen 2010/0228244 Al * 9/2010 Hancock. A61B 18/1815 7,118,590 Bl* 10/2006 Cronin . A61B 18/14 606/33 606/33 2010/0305561 Al 12/2010 Prakash et al. 7,194,297 B2 3/2007 Talpade et al. 2011/0034917 Al * 2/2011 Brannan A61B 18/00 7,226,446 Bl 6/2007 Mody et al. 606/41 7,826,904 B2 * 11/2010 Appling . A61B 18/18 2011/0208177 Al * 8/2011 Brannan A61B 18/1815 606/33 606/33 8,059,059 B2 * 11/2011 Bonn A61B 18/18 2011/0238060 Al 9/2011 Lee, Jr. et al. 343/793 2014/0358140 Al 1/2014 Emmons 8,280,525 B2 * 10/2012 Rusin. A61B 18/18 607/101 OTHER PUBLICATIONS 8,414,570 B2 4/2013 Turner et al. 2006/0189973 Al 8/2006 van der Weide International Search Report and Written Opinion for Intl. Patent 2009/0076492 Al* 3/2009 Behnke . A61B 18/18 606/33 Appl. No. PCT/US2015/012615, dated May 1, 2015, 10 pp. 2010/0057070 Al* 3/2010 Behnke . A61B 18/18 International Search Report and Written Opinion for PCT/US2018/ 606/33 067469, dated Apr. 18, 2019. 2010/0097284 Al 4/2010 Brannan et al. 2010/0125269 Al 5/2010 Emmons et al. * cited by examiner e• 00 • 100 ~ ~ ~ \ ~ =~ Coaxial cable 102 Impedance matching structure 104 Antenna 106 rJJ ('D '? QO ~ N 0 Fig. 1 N 0 100a rJJ ('D=- ('D..... 219 212 .... 1Q4a I ?10 /ft;-.._ ?~? \ 0 .... 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C"') ~~C"') . ~ e• 304 r:J)_ • 104a ~ 100a ~ ~ ~ 306 314 \ =~ .l .... rJJ ('D ..·············1 340 '? '"CIO N 0 N r I .... ;❖:·<,;• ❖: •x· X• »·»X· » :❖: ❖: ❖: •X•X• ❖l •X· X• » :❖:» » :❖: ❖: ;❖: ;❖:•❖: ., .,. X• ,.-v,,. ,.,., ., 0 312 ,. * ·~ 1219 i" t t t rc----""-------, rJJ ('D=­ • - •••• ,,,,,, •• - I· ('D .· '* ;&. ' .. :,::.~- . :❖::··si.~ . «·.• . : ..... {l *~, ,t•··,~•!f::,,,.,. /:❖::·\ ,. .i;... *' :~: :jj 0 \t f: « :*; :o;• Antenna 106c .... ·M: i- i :~· « :jj~· .... '*· «· O'I "'~: 326 ~- :{ii « *' ~ "",,, 322 « « :O·"' i:jj• ., -~ ':!Ii "' ® ~- s: ~­ :? t',.. ·t: 324 !<: ·:f:: . ... :~· 328 . • «: :,,:s I'I• ,~:... d •·:~ $J r.,;_ :;.; :9: : ·• .j:: ~ : ..~ ·lj: ·:S: ·«·";i-:._..:. : ·•· ~ "' 320 -..="'""' ....... ., ~ -....l ;,@, ~ 0--, UI ~ -....l Fig. 3c -....l =N e• 00 • 100b ~----1q4b ........)ll• f04: ·:t::!:i:;···· r ~ 210 106a ~ 204 318 ~ 354 302 \:, .. ~ 206 \ ,::(:::::35~:t:::::: .. :···············································:;:;:;:;::•:•· ~ I = ;t: ·~: ·~· ~: « !<'. )f ~ ::=: rJJ 300 ('D '? '"CIO N 0 N 312 0 350 *· -~­ ~ ~- ~ ~ • • rJJ ('D=­ ('D..... :···~·»'*'S!--X-:X-. 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U.S. Patent Sep. s, 2020 Sheet 8 of 16 US 10,765,477 B2 ..-0) N ... ,. ................ <:;j"' co0 .......... , .......... 0 0 N (.C) co 0co . 0) LL g/ ..-0 0 0 N N ..-0 U.S. Patent Sep.8,2020 Sheet 9 of 16 US 10,765,477 B2 LI) r--1 I I I I I I I 0~ r- l? ■ ~ 0) ■- LL g If I gag ,ij g I , I !ll Iii I I l "II g If g If g I g Ji I g ~ ~ 0 0 0 r- N 1 I U.S. Patent Sep.8,2020 Sheet 10 of 16 US 10,765,477 B2 0 . Lt") 0 0 .....0 co co co co0 co F·········l co ■ 0co E 0) ■- E LL t....-.l N ~ ~ I I I I I I I I II 1..,1 II I II II II II I I I I Ji II I I II I I I I II II 0 M 1 ~ 1111111111 0 0 LO 0 11,,r;l'I ·'°"'· .J 0N ~ I ~ [ww] /4 I U.S. Patent Sep.8,2020 Sheet 11 of 16 US 10,765,477 B2 - ~I C'v C C .....CD C: <( CD L.. :::, CD t, (.) :::, C '-- "Oro u50) "-ti0 0 CD C ...-- 0 Cl.·- ...-- - E .c - .....u ro E ~I 0) CD ..0 . C'v 0) (.) LL ·xro ro 0 (.) - ~I L.. .....0 (.) CD C C 0 (.) 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