Full-duplex antenna system and method

• US 7,184,727 B2
• Filed: 07/26/2004
• Issued: 02/27/2007
• Est. Priority Date: 02/12/2002
• Status: Expired due to Term

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Wireless Corporation (Kyocera Corporation)
• Inventors: Fabrega-Sanchez, Jorge, Poilasne, Gregory, Toncich, Stanley S., Tran, Allen
• Primary Examiner(s): NGUYEN, THUAN T
• Application Number:
  US10/899,285
• Publication Number:
  US 20050085204A1
• Time in Patent Office: 946 Days
• Field of Search: 455179- 1, 455/188.1, 455/269, 455/82, 455/562.1, 455/575.7, 343/700, 343/702, 343/745, 343/909, 343/860
• US Class Current: 455/179.1
• CPC Class Codes: G01R 27/2694 Measuring dielectric loss, e.g. loss angle, loss factor or power factor
• CPC Class Codes: H01G 7/06 having a dielectric selected for the variation of its permittivity with applied voltage, i.e. ferroelectric capacitors electrets H01G7/02
• CPC Class Codes: H01L 27/0808 Varactor diodes
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength
• CPC Class Codes: H03B 5/04 Modifications of generator to compensate for variations in physical values, e.g. power supply, load, temperature
• CPC Class Codes: H03B 5/1841 the frequency-determining element being a strip line resonator H03B5/1805, H03B5/1817, H03B5/1864 and H03B5/1882 take precedence
• CPC Class Codes: H03B 5/362 the amplifier being a single transistor H03B5/364 - H03B5/368 take precedence
• CPC Class Codes: H03F 1/56 Modifications of input or output impedances, not otherwise provided for
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/372 Noise reduction and elimination in amplifier
• CPC Class Codes: H03F 3/191 Tuned amplifiers H03F3/193, H03F3/195 take precedence
• CPC Class Codes: H03H 7/0123 comprising distributed impedance elements together with lumped impedance elements
• CPC Class Codes: H03H 7/12 Bandpass or bandstop filters with adjustable bandwidth and fixed centre frequency H03H7/09 takes precedence; automatic control of bandwidth in amplifiers H03G5/16
• CPC Class Codes: H03H 7/20 Two-port phase shifters providing an adjustable phase shift
• CPC Class Codes: H03H 7/40 Automatic matching of load impedance to source impedance
• CPC Class Codes: H03J 5/246 using electronic means H03J5/244 takes precedence
• CPC Class Codes: H03L 1/022 by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature H03L1/021 takes precedence
• CPC Class Codes: H03L 7/18 using a frequency divider or counter in the loop H03L7/20, H03L7/22 take precedence
• CPC Class Codes: H04B 1/0053 with common antenna for more than one band
• CPC Class Codes: H04B 1/0458 : Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 1/18 : Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: H04B 1/30 : for homodyne or synchrodyne receivers demodulator circuits H03D1/22

Abstract

A system and method is provided for full-duplex antenna impedance matching. The method comprises: effectively resonating a first antenna at a frequency selectable first channel in a first frequency band; generating a first antenna impedance at the first channel frequency; effectively resonating a second antenna at a frequency selectable second channel in the first frequency band; generating a second antenna impedance at the second channel frequency; supplying a first conjugate impedance match at the first channel frequency; and, supplying a second conjugate impedance match at the second channel frequency. For example, the first antenna may be used for transmission, while the second antenna is used for received communications. The antennas effectively resonant in response to: supplying frequency selectable conjugate impedance matches to the antennas; generating frequency selectable antenna impedances; and/or selecting the frequency of antenna resonance.

Claims

1. A full-duplex antenna system for selectively tuning communication channels, the system comprising:

a first antenna effectively resonant at a frequency selectable first channel in an first frequency band, having an interface port with a first impedance at the first channel frequency;

a second antenna effectively resonant at a frequency selectable second channel in the first frequency band, having an interface with a second impedance at the second channel frequency;

a first matching circuit including a port connected to the first antenna interface port having a first conjugate impedance at the first channel frequency; and

,

a second matching circuit including a port connected to the second antenna interface port having a second conjugate impedance at the second channel frequency.

2. The system of claim 1 wherein first matching circuit has a frequency selectable first conjugate impedance in the first frequency band;

and,

wherein the second matching circuit has a frequency selectable second conjugate impedance in the first frequency band.

3. The system of claim 2 wherein the first matching circuit includes:

a first tuning circuit; and

,

a second tuning circuit; and

,

wherein the second matching circuit includes;

a third tuning circuit; and

,

a fourth tuning circuit.

4. The system of claim 3 wherein the first tuning circuit includes:

a first inductor with a fixed inductance value;

a fifth variable capacitor with a selectable capacitance value; and

,

wherein the second tuning circuit includes;

a second inductor with a fixed inductance value;

a sixth variable capacitor with a selectable capacitance value.

wherein the third tuning circuit includes;

a third inductor with a fixed inductance value;

a seventh variable capacitor with a selectable capacitance value; and

,

wherein the fourth tuning circuit includes;

a fourth inductor with a fixed inductance value;

an eighth variable capacitor with a selectable capacitance value.

5. The system of claim 4 wherein the fifth, sixth, seventh, and eighth variable capacitors include:

a ferroelectric dielectric with a dielectric constant responsive to a control voltage; and

,

an interface to accept the control voltage.

6. The system of claim 5 wherein the ferroelectric variable capacitors are selected from the group including interdigital, gap, and overlay capacitors.

7. The system of claim 3 wherein the first and second matching circuits are a matching topology selected from the group including a tunable series element, a tunable shunt element, “

L”

, π

, “

T”

, and combinations of the above-mentioned topologies.

8. The system of claim 1 wherein first antenna has a selectable first impendance;

and,

wherein the second antenna has a selectable second impendance.

9. The system of claim 8 wherein the first antenna is an inverted-F antenna and further includes a third variable capacitor, connected in series with the matching circuit to vary the first impedance;

and,

wherein the second antenna is an inverted-F antenna and further includes a fourth variable capacitor, connected in series with the second matching circuit to vary the second impedance.

10. The system of claim 9 wherein the third and fourth variable capacitors include:

a ferroelectric dielectric with a dielectric constant responsive to a control voltage; and

,

an interface to accept the control voltage.

11. The system of claim 10 wherein the ferroelectric variable capacitors are selected from the group including interdigital, gap, and overlay capacitors.

12. The system of claim 8 wherein the first antenna is an inverted-F antenna and further includes a ninth variable capacitor, connected in series in a leg of a grounded resonator section, to vary the first impedance;

wherein the second antenna is an inverted-F antenna and further includes a tenth variable capacitor, connected in series in a leg of a grounded resonator section, to vary the second impedance.

13. The system of claim 12 wherein the ninth and tenth variable capacitors include:

a ferroelectric dielectric with a dielectric constant responsive to a control voltage; and

,

an interface to accept the control voltage.

14. The system of claim 1 wherein first antenna resonance is frequency selectable;

and,

wherein the second antenna resonance is frequency selectable.

15. The system of claim 14 wherein the first antenna is an inverted-F antenna and further includes a first variable capacitor, connected in shunt between an antenna radiator and a reference voltage to vary the frequency of resonance;

and,

wherein the second antenna is an inverted-F antenna and further includes a second variable capacitor, connected in shunt between an antenna radiator and the reference voltage to vary the frequency of resonance.

16. The system of claim 15 wherein the first and second variable capacitors include:

a ferroelectric dielectric with a dielectric constant responsive to a control voltage; and

,

an interface to accept the control voltage.

17. The system of claim 16 wherein the ferroelectric variable capacitors are selected from the group including interdigital, gap, and overlay capacitors.

18. The system of claim 1 wherein the first antenna effectively resonates at a frequency selectable third channel in a second frequency band, with a corresponding third impedance at the third channel frequency supplied at the interface;

wherein the second antenna effectively resonates a frequency selectable fourth channel in the second frequency band, with a corresponding fourth impedance at the fourth channel frequency supplied at the interface;

wherein the first matching circuit has a third conjugate impedance at the third channel frequency; and

,

wherein the second matching circuit has a fourth conjugate impedance at the fourth channel frequency.

19. The system of claim 18 wherein the first and second antennas resonate simultaneously in the first frequency band;

and,

wherein the first and second antennas resonate simultaneously in the second frequency band.

20. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 824 and 894 megahertz (MHz).

21. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 1850 and 1990 MHz.

22. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 880 and 960 MHz.

23. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 1710 and 1880 MHz.

24. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 1900 and 2100 MHz.

25. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 410 and 450 MHz.

26. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 2400 and 2480 MHz.

27. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 4900 and 5900 MHz.

28. The system of claim 1 wherein the first and second antennas resonate at first and second channels, respectively, for a first frequency band in the range between 1565 and 1585 MHz.

29. The system of claim 1 wherein the first antenna effectively resonates with an antenna efficiency of greater than 30%, respective to each channel in the first frequency band;

and,

wherein the second antenna effectively resonates with an antenna efficiency of greater than 30%, respective to each channel in the first frequency band.

30. The system of claim 29 wherein the first antenna has a first channel frequency span that is a fractional bandwidth of 0.0025, or greater, with respect to the first frequency band center frequency;

and,

wherein the second antenna has a second channel frequency span that is a fractional bandwidth of 0.0025, or greater, with respect to the first frequency band center frequency.

31. The system of claim 1 wherein the first and second antennas are antennas selected from the group including inverted-F, monopole, dipole, horn, loop, helix, traveling wave, quadrifilar helix, balanced, unbalanced antennas, electric dipole, magnetic dipole, and capacitively-loaded magnetic dipole antennas.

32. The system of claim 1 wherein the first antenna receives radiated communications;

and,

wherein the second antenna transmits radiated communications.

33. The system of claim 1 further comprising:

a plurality of antennas, each effectively resonant at a frequency selectable channel in a frequency band, and having an interface port with a impedance at the selected channel frequency; and

,

a plurality of matching circuits, each having a port connected to a corresponding antenna interface port having a conjugate impedance at the selected channel frequency.

34. The system of claim 33 wherein the plurality of antennas simultaneously effectively resonate at a different channel.

35. The system of claim 33 wherein the plurality of antennas simultaneously effectively resonate at the same channel.

36. A wireless telephone with a full-duplex antenna matching system, the telephone comprising:

a transceiver having a transmit port and a receiver port to process antenna communications in a first frequency band;

a first antenna effectively resonant at a frequency selectable first channel in an first frequency band, having an interface port with a first impedance at the first channel frequency;

a second antenna effectively resonant at a frequency selectable second channel in the first frequency band, having an interface with a second impedance responsive at the second channel frequency;

a first matching circuit having an output port connected to the first antenna interface port with a first conjugate impedance at the first channel frequency, and an input port connected to the transceiver transmit port; and

,

a second matching circuit having an input port connected to the second antenna interface port with a second conjugate impedance at the second channel frequency, and an output port connected to the transceiver receive port.

37. The telephone of claim 36 wherein first matching circuit has a frequency selectable first conjugate impedance in the first frequency band;

and,

wherein the second matching circuit has a frequency selectable second conjugate impedance in the first frequency band.

38. The telephone of claim 36 wherein first antenna has a selectable first impedance;

and,

wherein the second antenna has a selectable second impedance.

39. The telephone of claim 36 wherein first antenna resonance is frequency selectable;

and,

wherein the second antenna resonance is frequency selectable.

40. The telephone of claim 36 wherein the transceiver additionally processes antenna communications is a second frequency band;

wherein the first antenna effectively resonates at a frequency selectable third channel in the second frequency band, with a corresponding third impedance at the third channel frequency;

wherein the second antenna effectively resonates at a frequency selectable fourth channel in the second frequency band, with a corresponding fourth impedance at the fourth channel frequency;

wherein the first matching circuit has a third conjugate impedance at the third channel frequency; and

,

wherein the second matching circuit has a fourth conjugate impedance at the fourth channel frequency.

41. The telephone of claim 40 wherein the first and second antennas resonate simultaneously in the first frequency band;

and,

wherein the first and second antennas resonate simultaneously in the second frequency band.

42. A method for full-duplex antenna impedance matching, the method comprising:

effectively resonating a first antenna at a frequency selectable first channel in a first frequency band;

generating a first antenna impedance at the first channel frequency;

effectively resonating a second antenna at a frequency selectable second channel in the first frequency band;

generating a second antenna impedance at the second channel frequency;

supplying a first conjugate impedance match at the first channel frequency; and

,

supplying a second conjugate impedance match at the second channel frequency.

43. The method of claim 42 wherein supplying a first conjugate impedance match at the first channel frequency includes supplying a frequency selectable first conjugate impedance;

and,

wherein supplying a second conjugate impedance match at the second channel frequency includes supplying a frequency selectable second conjugate impedance.

44. The method of claim 42 wherein generating a first antenna impedance at the first channel frequency includes generating a frequency selectable first impedance;

and,

wherein generating a second antenna impedance at the second channel frequency includes generating a frequency selectable second impedance.

45. The method of claim 42 wherein effectively resonating a first antenna at a frequency selectable first channel in a first frequency band includes selecting the frequency of resonance;

and,

wherein effectively resonating a second antenna at a frequency selectable second channel in a first frequency band includes selecting the frequency of resonance.

46. The method of claim 42 further comprising:

effectively resonating the first antenna at a frequency selectable third channel in a second frequency band;

generating a third antenna impedance at the third channel frequency;

effectively resonating the second antenna at a frequency selectable fourth channel in the second frequency band;

generating a fourth antenna impedance at the fourth channel frequency;

supplying a third conjugate impedance match at the third channel frequency; and

,

supplying a fourth conjugate impedance match at the fourth channel frequency.

47. The method of claim 46 wherein the first and second antennas resonate simultaneously at the first and second channels, respectively;

and,

wherein the first and second antennas resonate simultaneously at the third and fourth channels, respectively.

48. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 824 and 894 megahertz (MHz).

49. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 1850 and 1990 MHz.

50. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 880 and 960 MHz.

51. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 1710 and 1880 MHz.

52. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 1900 and 2100 MHz.

53. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 410 and 450 MHz.

54. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 2400 and 2480 MHz.

55. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 4900 and 5900 MHz.

56. The method of claim 42 wherein the first and second channels are resonate in a first frequency band in the range between 1565 and 1585 MHz.

57. The method of claim 42 wherein effectively resonating a first antenna at a frequency selectable first channel in a first frequency band includes transmitting information via the first channel;

and,

wherein effectively resonating a second antenna at a frequency selectable second channel in a first frequency band includes receiving information via the second channel.

58. The method of claim 42 further comprising:

effectively resonating a plurality of antennas at a frequency selectable channel in the first frequency band;

generating an impedance at each channel frequency; and

,

supplying a conjugate impedance match at each channel frequency.

59. The method of claim 42 wherein effectively resonating a first antenna at a frequency selectable first channel in a first frequency band includes resonating with an efficiency of greater than 30% at every channel in the first frequency band;

and,

wherein effectively resonating a second antenna at a frequency selectable second channel in a first frequency band includes resonating with an efficiency of greater than 30% at every channel in the first frequency band.