US008098756B2 (12) United States Patent Yamamoto et a1. (10) Patent N0.: (45) Date of Patent: US 8,098,756 B2 Jan. 17, 2012 (54) (75) (73) ( * ) (21) (22) (86) (87) (65) (30) (51) (52) (58) MIMO ANTENNA APPARATUS CAPABLE OF DIVERSITY RECEPTION USING ONE RADIATING CONDUCTOR Inventors: Atsushi Yamamoto, Kyoto (JP); Hiroshi IWai, Osaka (JP); Satoru Amari, Osaka (JP); Tsutomu Sakata, Osaka (JP) Assignee: Panasonic Corporation, Osaka (JP) Notice: May 22, 2008 Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 192 days. Appl. No.: 12/670,200 PCT Filed: May 19, 2009 PCT No.: 371 (0X1) (2), (4) Date: PCT/JP2009/002199 Jan. 22, 2010 PCT Pub. No.: WO2009/142000 PCT Pub. Date: Nov. 26, 2009 Prior Publication Data US 2010/0195753 A1 Aug. 5,2010 Foreign Application Priority Data (JP)..... 2008-133939 Int. Cl. H04L 1/02 (2006.01) H04B 7/02 (2006.01) US. Cl...... 375/267; 375/316; 375/347; 370/334; 455/101; 343/770 Field of Classi?cation Search..... 375/267, 375/316, 347; 455/101; 370/334; 343/770 See application?le for complete search history. (56) References Cited U.S. PATENT DOCUMENTS 7,053,848 B2 * 5/2006 Shoji et al...... 343/770 7,778,147 B2 * 8/2010 ForenZa et al. 370/204 7,864,121 B2 * 1/2011 Suprunov et al...... 343/702 2004/0239575 A1 12/2004 Shoji et a1. FOREIGN PATENT DOCUMENTS JP 8-97760 4/1996 JP 2004-56421 2/2004 (Continued) OTHER PUBLICATIONS International Search Report issued Aug. 25, 2009 in International (PCT) Application No. PCT/JP2009/ 002199. (Continued) Primary Examiner * Ted Wang (74) Attorney, Agent, or Firm * Wenderoth, Lind & Ponack, L.L.P. (57) ABSTRACT A MIMO antenna apparatus is provided With: an upper hous ing having slits;?rst feed points through Which the upper housing itself is excited as?rst antennas; second feed points through Which the slits are excited as second antennas; switch, each of Which is connected to one of the?rst feed points and one of the second feed points, and connects one of the two feed points to an A/D converter circuit-; a signal level detector circuit detecting signal levels of received radio sig nals; and a controller that controls the switches to change a feed point connected to the A/D converter circuit, When the detected signal level is less than or equal to a predetermined threshold value. The slits are located between the?rst anten nas. 11 Claims, 21 Drawing Sheets MIMO ADAPTIVE CONTROL PROCESS CONTROL SWITCHING CIRCUIT 4T0 CONNECT ANTENNAS 15 AND 117 T0 AID CONVERTER CIRCUIT 5 S2 IS SIGNAL LEVEL OF ANTENNA 1b HIGHER THAN THRESHOLD VALUE 7 Y NO CONTROL SIMTCHING CIRCUIT 4 T0 CONNECT NI'I'ENNA 2 I: TU NO CONVERTER CIRCUIT 5
US 8,098,756 B2 Page 2 JP JP JP JP JP FOREIGN PATENT DOCUMENTS 2004-129234 2005-236884 2005-347958 2006-166261 2008-60907 4/2004 9/2005 12/2005 6/2006 3/2008 WO 2008/047441 4/2008 OTHER PUBLICATIONS International Preliminary Report on Patentability issued Jan. 20, 2011 in International (PCT) Application No. PCT/JP2009/002l99. * cited by examiner
US. Patent Jan. 17, 2012 Sheet 1 0f 21 US 8,098,756 B2.m gm mm 2 G... -- m!) P f O (\TM? EEm>z8 Q2 /\/m 35%; 526 Y 20:62:58 1853850 925 Sm P526 J B E 26%
US. Patent Jan. 17, 2012 Sheet 3 0f 21 US 8,098,756 B2 11% ELECTRIC FIELD A DISTRIBUTION FOR ANTENNA 1a \_/\ //_./// é A ELECTRIC FIELD / DISTRIBUTION FOR / ANTENNA 1b /\/ 4 / / // 113a /, - A7 /13b 13 / 7/ V13c 1a/ 10V /_ \-1b 12% k J
US. Patent Jan. 17, 2012 Sheet 4 0f 21 US 8,098,756 B2 Fig.4 ("\\\\\\\\\\\L\\ / 11%,/13a 13b 13 ;/ 130 10~/ 12%
US. Patent Jan. 17, 2012 Sheet 5 0f 21 Fig.5 @mvlo ADAPTIVE CONTROL PROCESS) US 8,098,756 B2 S1 CONTROL SWITCHING CIRCUIT 4T0 CONNECT ANTENNAS 1a AND 1b TO AID CONVERTER CIRCUIT 5 S2 IS SIGNAL LEVEL OF ANTENNA 1a HIGHER THAN THRESHOLD VALUE? S3 IS SIGNAL LEVEL OF ANTENNA 1b HIGHER THAN THRESHOLD VALUE? $4 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 2b TO A/D CONVERTER CIRCUIT 5 S9 CONTINUE DEMODULATION PROCESS S5 IS SIGNAL LEVEL OF ANTENNA 2b HIGHER THAN SIGNAL LEVEL OF ANTENNA 1b? S10 EXCEED PREDETERMINED NUMBER OF DEMODULATIONS? S6 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 1b TO AID CONVERTER CIRCUIT 5 S7 CONTINUE DEMODULATION PROCESS EXCEED PREDETERMINED NUMBER OF DEMODULATIONS?
US. Patent Jan. 17, 2012 Sheet 6 0f 21 US 8,098,756 B2 Fig. 6 S11 IS SIGNAL LEVEL OF ANTENNA 1b HIGHER THAN THRESHOLD VALUE? CONTROL SWITCHING CIRCUIT 4 TO 312 CONNECT ANTENNA 2a TO AID CONVERTER CIRCUIT 5 S13 IS SIGNAL LEVEL OF ANTENNA 2a HIGHER THAN SIGNAL LEVEL OF ANTENNA 1a? S14 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 1a TO AID CONVERTER CIRCUIT 5 4 S15 CONTINUE DEMODULATION PROCESS S16 NO EXCEED PREDETERMINED NUMBER OF DEMODULATIONS?
US. Patent Fig. 7 Jan. 17, 2012 Sheet 7 0f 21 US 8,098,756 B2 S17 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNAS 2a AND 2b TO A/D CONVERTER CIRCUIT 5 S18 IS SIGNAL LEVEL OF ANTENNA 2a HIGHER THAN THRESHOLD VALUE? S19 IS SIGNAL LEVEL OF ANTENNA 2b HIGHER THAN THRESHOLD VALUE? S20 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 1b TO AID CONVERTER CIRCUIT 5 S25 CONTINUE DEMODULATION PROCESS S21 IS SIGNAL LEVEL OF ANTENNA 1b HIGHER THAN SIGNAL LEVEL OF ANTENNA 2b? S26 EXCEED PREDETERMINED NUMBER OF DEMODULATIONS? S22 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 2b TO AID CONVERTER CIRCUIT 5 S23 CONTINUE DEMODULATION PROCESS 524 NO EXCEED PREDETERMINED NUMBER OF DEMODULATIONS?
US. Patent Jan. 17, 2012 Sheet 8 0f 21 US 8,098,756 B2 Fig. 8 S27 IS SIGNAL LEVEL OF ANTENNA 2b HIGHER THAN THRESHOLD VALUE? CONTROL SWITCHING CIRCUIT 4 S28 T0 CONNECT ANTENNA 1a TO A/D CONVERTER CIRCUIT 5 S29 IS SIGNAL LEVEL OF ANTENNA 1a HIGHER THAN SIGNAL LEVEL OF ANTENNA S33 ARE SIGNAL LEVELS OF ANTENNAS 2a AND 2b HIGHER THAN SIGNAL LEVELS OF ANTENNAS 1a AND 1b? s34 CONTROL SWITCHING CIRCUIT 4 CONTROL SWITCHING CIRCUIT 4 530 TO CONNECT ANTENNA 2a T0 T0 CONNECT ANTENNAS 1a AND A/D CONVERTER CIRCUIT 5 1b TO A/D CONVERTER CIRCUIT 5 s35 < ~ *~ S31 CONTINUE DEMODULATION CONTINUE DEMODULATION PROCESS PROCESS EXCEED S36 EXCEED PREDETERMINED PREDETERMINED NUMBER OF NUMBER OF DEMODULATIONS? NO DEMODULATIONS '2
US. Patent Jan. 17, 2012 Sheet 9 0f 21 US 8,098,756 B2 m w 5 \IAHICIL.2205 $54 )JIUL 292528; 9.850 Al 156528 E05: 5.26 I lg? m... LIN? U7 _ 2... mwemszoo 02 gm 526 EESDSEQ 022 Sm F585 A @.mt
US. Patent Jan. 17 2012 Sheet 11 0121 US 8,098,756 B2 10%
US. Patent Jan. 17, 2012 Sheet 12 0f 21 US 8,098,756 B2 w i wézoa w 2w WEE; ms? _ P5016 EOE: it\/ m l Qv/m... Q2 mwew>z8 N <w <@ Sm Y zw?o?pw?wo x8850 205522; Alv 156528 K28 ézwa P5016 2928c @ m MN mm? QM aw 56% o_> >_ EESDQOEQ Sm 5E6.mt 2
US. Patent Jan. 17, 2012 Sheet 13 0f 21 US 8,098,756 B2 Fig. 13 (\NMC ADAPTIVE CONTROL PROCESS) >I< CONTROL SWITCHING CIRCUIT 4 TO 341 CONNECT ANTENNAS 1a AND 1b TO AID CONVERTER CIRCUIT 5 (F) S42 IS SIGNAL LEVEL OF ANTENNA 1a HIGHER THAN THRESHOLD VALUE? S43 IS SIGNAL LEVEL OF ANTENNA 1b HIGHER THAN THRESHOLD VALUE? s49 CONTROL SWITCHING CIRCUIT 4 TO CONTINUE s44 CONNECT ANTENNA 2b T0 DEMODULATION PROCESS AID CONVERTER CIRCUIT 5 I S50 IS SIGNAL EXCEED S45 QUALITY OF ANTENNA 2b PREDETERMINED BE'I'I' R AN IGNAL LITY NUMBER OF E OF TH ANTENNA S 1b? QUA DEMODULATIONS? CONTROL SWITCHING CIRCUIT 4 TO 846 CONNECT ANTENNA 1b TO AID CONVERTER CIRCUIT 5 K.. 847 CONTINUE DEMODULATION PROCESS S48 NO EXCEED PREDETERMINED NUMBER OF DEMODULATIONS?
I US. Patent Jan. 17, 2012 Sheet 14 0f 21 US 8,098,756 B2 Fig. 1 4 S51 IS SIGNAL LEVEL OF ANTENNA 1b HIGHER THAN THRESHOLD VALUE? S52 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 2a TO A/D CONVERTER CIRCUIT 5 IS SIGNAL QUALITY OF ANTENNA 2a BETTER THAN SIGNAL QUALITY OF ANTENNA 1a? s53 CONTROL SWITCHING CIRCUIT 4 TO S54 CONNECT ANTENNA 1a TO AID CONVERTER CIRCUIT 5 ( S55 CONTINUE DEMODULATION PROCESS S56 NO EXCEED PREDETERMINED NUMBER OF DEMODULATIONS?
US. Patent Jan. 17, 2012 Sheet 15 0f 21 US 8,098,756 B2 Fig. 1 5 S57 @ CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNAS 2a AND 2b TO AID CONVERTER CIRCUIT 5 S58 IS SIGNAL LEVEL OF ANTENNA 2a HIGHER THAN THRESHOLD VALUE? S59 IS SIGNAL LEVEL OF ANTENNA 2b HIGHER THAN THRESHOLD VALUE? S60 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 1b TO AID CONVERTER CIRCUIT 5 S65 CONTINUE DEMODULATION PROCESS S61 r IS SIGNAL QUALITY OF ANTENNA 1b OF ANTENNA 2b? S66 EXCEED PREDETERMINED NUMBER OF DEMODULATIONS? S62 CONTROL SWITCHING CIRCUIT 4 TO CONNECT ANTENNA 2b TO A/D CONVERTER CIRCUIT 5 S63 CONTINUE DEMODULATION PROCESS S64 NO EXCEED PREDETERMINED NUMBER OF DEMODULATIONS?
US. Patent Jan. 17, 2012 Sheet 16 0f 21 US 8,098,756 B2 Fig. 16 S67 IS SIGNAL LEVEL OF ANTENNA 2b HIGHER THAN THRESHOLD VALUE.7 CONTROL SWITCHING CIRCUIT 4 S68 T0 CONNECT ANTENNA 1a TO I A/D CONVERTER CIRCUIT 5 V S69 IS SIGNAL S73 ARE SIGNAL QUALITY OF LEVELS OF ANTENNAS ANTENNA 1a BETTER 2a AND 2b HIGHER THAN THAN SIGNAL QUALITY S GNAL LEVELS OF 0F ANTENNA ANTENNAS 1a 2a? AND 1b? S74 N0 CONTROL SWITCHING CIRCUIT 4 S70 T0 CONNECT ANTENNA 2a T0 CONTROL SWITCHING CIRCUIT 4 T0 CONNECT ANTENNAS 1a AND AID CONVERTER CIRCUIT 5 1b TO A/D CONVERTER CIRCUIT 5 * T 875 < 871 CONTINUE DEMODULATION CONTINUE DEMODULATION PROCESS PROCESS EXCEED PREDETERMINED NUMBER OF DEMODULATIONS? S76 EXCEED PREDETERMINED NUMBER OF NO DEMODULATIONS?
US. Patent Jan. 17, 2012 Sheet 17 0f 21 US 8,098,756 B2 <@ E zo:<_>_~_o _z_ Iv $83.50 Al @6528 Alf E95: 595 All. é?ww wézwa {jrjwllf \ ma: A e ink/v m... >550 ézwa mm 22% QESDQOEQ J _ 6:... zoaama P586 J QM mm W (\Tmw 1 mat/1:850 oz: Q6 5516 V?Emszoo Q2 222222228 /\/m P525 02 P5016 2.mt wwwmmé
US. Patent Jan. 17, 2012 Sheet 18 0f 21 US 8,098,756 B2 é/z/afm f/é/évz mm m % b B 4&7 // q i, 12%