Adaptive impedance matching apparatus, system and method

• US 20080106349A1
• Filed: 11/08/2006
• Published: 05/08/2008
• Est. Priority Date: 11/08/2006
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Paratek Microwave Incorporated (Blackberry Limited)
• Inventors: McKinzie, William E.
• Granted Patent: US 7,714,676 B2
• Time in Patent Office: Days
• US Class Current: 333/17.3
• CPC Class Codes: H01Q 1/50 Structural association of antennas with earthing switches, lead-in devices or lightning protectors
• CPC Class Codes: H03H 11/30 Automatic matching of source impedance to load impedance
• CPC Class Codes: H03H 7/38 Impedance-matching networks
• CPC Class Codes: H03H 7/40 Automatic matching of load impedance to source impedance
• CPC Class Codes: H04B 1/44 Transmit/receive switching
• CPC Class Codes: H04L 25/0278 Arrangements for impedance matching
• CPC Class Codes: H04W 52/18 TPC being performed according to specific parameters

Abstract

An embodiment of the present invention provides an apparatus, comprising an RF matching network connected to at least one RF input port and at least one RF output port and including one or more voltage or current controlled variable reactive elements and wherein the RF matching network is adapted to maximize RF power transferred from the at least one RF input port to the at least one RF output port by varying the voltage or current to the voltage or current controlled variable reactive elements to maximize the RF voltage at the at least one RF output port. The variable reactive elements may be variable capacitances, variable inductances, or both.

Claims

1. An apparatus, comprising:

an RF matching network connected to at least one RF input port and at least one RF output port and including one or more voltage or current controlled variable reactive elements; and

wherein said RF matching network is adapted to maximize RF power transferred from said at least one RF input port to said at least one RF output port by varying the voltage or current to said voltage or current controlled variable reactive elements to maximize the RF voltage at said at least one RF output port.

2. The apparatus of claim 1, wherein said variable reactive elements are variable capacitances, variable inductances, or both.

3. The apparatus of claim 1, wherein said variable reactive elements include variable capacitors or variable inductors. (how does this differ claim 2?)

4. The apparatus of claim 3, wherein said variable capacitors are selected from the group consisting of:

semiconductor varactors;

MEMS varactors;

MEMS switched capacitors;

ferroelectric capacitors.

5. The apparatus of claim 3, wherein said variable inductors are switched inductors using various types of RF switches including MEMS-based switches.

6. The apparatus of claim 3, wherein said variable capacitors are at least one voltage tunable dielectric capacitors.

7. The apparatus of claim 6, wherein said at least one voltage tunable dielectric capacitor is a series network of voltage tunable dielectric capacitors which are all tuned using a common tuning voltage.

8. The apparatus of claim 1, further comprising a voltage detector connected to said at least one RF output port to determine the voltage at said at least one RF output port and provide voltage information to a controller that controls a bias driving circuit which provides voltage or current bias to said RF matching network.

9. The apparatus of claim 1, wherein said at least one RF input port is a plurality of RF input ports.

10. The apparatus of claim 1, wherein a load impedance associated with said at least one RF output port is from a multi-band antenna in a mobile wireless device and said RF matching network is a diplexer whose function is to direct the signal between two paths by virtue of the signal frequency.

11. An adaptive impedance matching system, comprising:

an RF matching network connected to at least one RF input port and at least one RF output port and including one or more voltage or current controlled variable reactive elements;

a voltage detector connected to said at least one RF output port to determine the voltage at said at least one RF output port and provide voltage information to a controller that controls a bias driving circuit which provides voltage or current bias to said RF matching network; and

wherein said RF matching network is adapted to maximize RF power transferred from said at least one RF input port to said at least one RF output port by varying the voltage or current to said voltage or current controlled variable reactive elements to maximize the RF voltage at said at least one RF output port.

12. The system of claim 11, wherein said variable reactive elements are variable capacitances, variable inductances, or both.

13. The system of claim 11, wherein said variable reactive elements include variable capacitors or variable inductors. (different from claim 12?)

14. The system of claim 13, wherein said variable capacitors are selected from the group consisting of:

semiconductor varactors;

MEMS varactors;

MEMS switched capacitors;

ferroelectric capacitors.

15. The system of claim 13, wherein said variable inductors are switched inductors using various types of RF switches including MEMS-based switches.

16. The system of claim 13, wherein said variable capacitors are at least one voltage tunable dielectric capacitors.

17. The system of claim 16, wherein said at least one voltage tunable dielectric capacitor is a series network of voltage tunable dielectric capacitors which are all tuned using a common tuning voltage.

18. A method of adaptive impedance matching, comprising:

connecting an RF matching network including one or more voltage or current controlled variable reactive elements to at least one RF input port and at least one RF output port; and

adapting said RF matching network to maximize RF power transferred from said at least one RF input port to said at least one RF output port by varying the voltage or current to said voltage or current controlled variable reactive elements to maximize the RF voltage at said at least one RF output port.

19. The method of claim 18, wherein said variable reactive elements are variable capacitances, variable inductances, or both.

20. The method of claim 18, including variable capacitors or variable inductors as said variable reactive elements. (??)

21. The method of claim 20, further comprising using variable capacitors selected from the group consisting of:

semiconductor varactors;

MEMS varactors;

MEMS switched capacitors;

ferroelectric capacitors.

22. The method of claim 20, wherein said variable inductors are switched inductors using various types of RF switches including MEMS-based switches.

23. The apparatus of claim 20, wherein said variable capacitors are at least one voltage tunable dielectric capacitors.

24. The apparatus of claim 23, further comprising tuning, using a common tuning voltage, a series network of voltage tunable dielectric capacitors as said at least one voltage tunable dielectric capacitor.

25. The apparatus of claim 18, further comprising using a voltage detector connected to said at least one RF output port to determine the voltage at said at least one RF output port and to provide voltage information to a controller that controls a bias driving circuit which provides voltage or current bias to said RF matching network.

26. A machine-accessible medium that provides instructions, which when accessed, cause a machine to perform operations comprising:

adapting an RF matching network to maximize RF power transferred from at least one RF input port to at least one RF output port by controlling the variation of the voltage or current to voltage or current controlled variable reactive elements in said RF matching network to maximize the RF voltage at said at least one RF output port.

27. The machine-accessible medium of claim 26, further comprising said instructions causing said machine to perform operations further comprising receiving information from a voltage detector connected to said at least one RF output port which determines the voltage at said at least one RF output port.

28. The machine-accessible medium of claim 26, further comprising said instructions causing said machine to perform operations further comprising providing voltage information to a controller that controls a bias driving circuit which provides voltage or current bias to said RF matching network.