Tunable microwave devices with auto-adjusting matching circuit

• US 7,865,154 B2
• Filed: 10/08/2005
• Issued: 01/04/2011
• Est. Priority Date: 07/20/2000
• Status: Expired due to Term

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Paratek Microwave Incorporated (Blackberry Limited)
• Inventors: du Toit, Cornelis Frederik, Khayo, Izz, McKinzie, William, Bachmann, Heinz, Martin, James Andrew III, Mendolia, Greg
• Primary Examiner(s): Le; Thanh C
• Application Number:
  US11/245,898
• Publication Number:
  US 20060160501A1
• Time in Patent Office: 1,914 Days
• Field of Search: 455/91, 455/121, 455/123, 455/124, 455/125, 455/129, 333/134, 333/133, 333/175, 333/178
• US Class Current: 455/125
• CPC Class Codes: H01P 5/04 with variable factor of coupling
• CPC Class Codes: H01Q 1/242 specially adapted for hand-held use
• CPC Class Codes: H03F 1/56 Modifications of input or output impedances, not otherwise provided for
• CPC Class Codes: H03F 3/60 Amplifiers in which coupling networks have distributed constants, e.g. with waveguide resonators H03F3/54 takes precedence
• CPC Class Codes: H03H 7/40 Automatic matching of load impedance to source impedance
• 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

Abstract

An embodiment of the present invention provides an apparatus, comprising an input port and a dynamic impedance matching network capable of determining a mismatch at the input port and dynamically changing the RF match by using at least one matching element that includes at least one voltage tunable dielectric capacitor. The matching network may be a “Pi”, a “T”, or “ladder” type network and the apparatus may further comprise at least one directional coupler capable of signal collection by sampling a portion of an incident signal, a reflected signal or both. In an embodiment of the present invention, the apparatus may also include a control and power control & logic unit (PC LU) to convert input analog signals into digital signals and sensing VSWR phase and magnitude and processing the digital signals using an algorithm to give it a voltage value and wherein the voltage values may be compared to values coming from the coupler and once compared and matched, the values may be passed to a Hi Voltage Application Specific Integrated Circuit (HV ASIC) to transfer and distribute compensatory voltages to the matching network elements.

Claims

1. An apparatus, comprising:

an input port;

a dynamic impedance matching network capable of determining a mismatch at said input port and dynamically changing the RF match by using at least one matching element that includes at least one voltage tunable dielectric capacitor;

at least one directional coupler capable of signal collection by sampling a portion of an incident signal, a reflected signal or both; and

a control and power control &

logic unit (PC LU) to convert input analog signals into digital signals and sensing VSWR phase and magnitude and processing said digital signals using an algorithm that produces voltage values and wherein said voltage values are determined from a comparison of values coming from said coupler and once compared, said voltage values are passed to a high voltage circuit to transfer and distribute compensatory voltages to said matching network elements.

2. The apparatus of claim 1, wherein said matching network is a “

Pi”

type network, and wherein the high voltage circuit comprises an Application Specific Integrated Circuit (ASIC).

3. The apparatus of claim 1, wherein the compared values are VSWR values.

4. The apparatus of claim 3, wherein the VSWR values comprise at least current and previous VSWR values.

5. The apparatus of claim 1, wherein said sampling is accomplished by at least one low impedance capacitor sampling element.

6. The apparatus of claim 5, wherein said sampling element is an interdigital capacitor or metal-insulator-metal (MIM) capacitor.

7. The apparatus of claim 1, wherein said matching network is a “

T”

type network.

8. The apparatus of claim 1, wherein said matching network is a “

ladder”

type network.

9. The apparatus of claim 8, wherein said “

ladder”

type network comprises at four inductors in series and includes three grounded matching capacitors in parallel connected to said inductors.

10. The apparatus of claim 1, wherein said dynamic impedance matching network is mounted onto a low-cost thermally conductive dielectric substrate with components surface mounted on one side, then over-molded as a Multi-Chip-Module (MCM), which is itself surface mountable on to a printed wiring board of an RF device.

11. The apparatus of claim 1, wherein said dynamic impedance matching network system is positioned between a Power Amplifier (PA) unit and a frequency filter unit in said apparatus.

12. The apparatus of claim 1, wherein said apparatus is a mobile phone and further comprises an external digital signal processor to convert input analog signals into digital signals and sensing VSWR phase and magnitude and processing said digital signals using an algorithm to give it a voltage value and wherein said voltage values are compared to values coming from said coupler and once compared and matched, compensatory voltages are transferred and distributed to said matching network elements.

13. The apparatus of claim 1, wherein said apparatus is a mobile phone and said dynamic impedance matching network system is positioned between a frequency filter unit and a switch unit in said mobile phone.

14. The apparatus of claim 1, wherein said dynamic impedance matching network is a single stand-alone component that is placed in the transmit chain of a mobile phone radio.

15. The apparatus of claim 1, wherein said apparatus is a mobile phone and said dynamic impedance matching network is self-contained thereby requiring only a fixed DC bias 3V from said mobile phone.

16. The apparatus of claim 15, wherein said same self-contained dynamic impedance matching network system enables impedance matching and therefore operation in a GSM, EDGE, CDMA or WCDMA or multi-mode mobile phone, and at least capable of a single band operation that includes 800, 900, 1800, 1900 MHz bands and the 2.1 GHz band.

17. A method, comprising:

matching an impedance presented to an RF signal received by an input port of a dynamic impedance matching network capable of determining a mismatch at said input port and dynamically changing the RF match by using at least one matching element that includes at least one voltage tunable dielectric capacitor,

wherein the dynamic matching network determines said mismatch according to signals collected by at least one directional coupler that samples a portion of an incident signal, a reflected signal or both, and

wherein the dynamic matching network adjusts the impedance presented to the RF signal responsive to a voltage control and power control &

logic unit (PC LU) that converts the collected-signals into digital signals, VSWR and processes said digital signals using an algorithm to produce one or more voltage values and wherein said one or more voltage values are determined from a comparison of digital values and once compared, said one or more voltage values are passed to a high voltage circuit to transfer and distribute one or move compensatory voltages to said at least one matching element.

18. The method of claim 17, wherein said matching network is a “

Pi”

type network, and wherein the high voltage circuit comprises an Application Specific Integrated Circuit (ASIC).

19. The method of claim 17. wherein the compared digital values are VSWR values.

20. The method of claim 17, wherein the VSWR values comprise at least current and previous VSWR values.

21. The method of claim 17, wherein said sampling is accomplished by at least one low impedance capacitor sampling element.

22. The method of claim 21, wherein said sampling element is an interdigital capacitor or metal-insulator-metal (MIM) capacitor.

23. The method of claim 17, wherein said at least one matching element comprise at least one micromachined tunable capacitor.

24. The method of claim 17, wherein said matching network is a “

ladder”

type network.

25. The method of claim 24, wherein said “

ladder”

type network comprises at four inductors in series and includes three grounded matching capacitors in parallel connected to said inductors.

26. The method of claim 17, further comprising mounting said dynamic impedance matching network onto a low-cost thermally conductive dielectric substrate such with components surface mounted on one side, then over-molded as a Multi-Chip-Module (MCM), which is itself surface mountable on to a printed wiring board of an RF device.

27. The method of claim 17, further comprising positioning said dynamic impedance matching network system between a Power Amplifier (PA) unit and a frequency filter unit in said apparatus.

28. The method of claim 17, further comprising using an external digital signal processor to convert input analog signals into digital signals and sensing VSWR phase and magnitude and processing said digital signals using an algorithm to give it a voltage value and wherein said voltage value is compared to values coming from said coupler and once compared and matched, compensatory voltages are transferred and distributed to said matching network elements.

29. The method of claim 17, further comprising positioning said dynamic impedance matching network system between a frequency filter unit and a switch unit in a mobile phone.

30. The method of claim 17, further comprising making said dynamic impedance matching network a single stand-alone component that is placed in the transmit chain of a mobile phone radio.

31. The method of claim 17, further comprising self containing said dynamic impedance matching network thereby requiring only a fixed DC bias 3V from said mobile phone.

32. The method of claim 31, wherein said same self contained dynamic impedance matching network system enables impedance matching and therefore operation in a GSM, EDGE, CDMA or WCDMA or multi-mode mobile phone, and at least capable of a single band operation that includes 800, 900, 1800, 1900 MHz bands and the 2.1 GHz band.

33. An auto-adjusting matching circuit, comprising:

a matching network to receive an incoming signal at an input port of the matching network, wherein the matching network includes a plurality of matching network elements comprising voltage tunable dielectric capacitors, wherein said matching network is capable of automatically adjusting an impedance presented to said incoming signal,

wherein a coupler samples a portion of an incident signal, a reflected signal or both at the input port; and

wherein said impedance is adjusted by a power control &

logic unit adapted to convert input analog signals into digital signals, sense VSWR phase and magnitude, and process said digital signals using an algorithm that produces voltage values, and wherein said voltage values are determined from a comparison of values coming from said coupler and once compared, said voltage values are passed to a voltage circuit to transfer and distribute one or more compensatory voltages to said plurality of matching network elements.

34. The auto-adjusting matching circuit of claim 33, wherein the VSWR values comprise at least current and previous VSWR values.

35. The auto-adjusting matching circuit of claim 33, wherein said voltage tunable dielectric capacitors correspond and to at least one of a micromachined tunable capacitors, capacitors with a variable dielectric, and semiconductor variable capacitors.