Compensating for load pull in electromagentic signal propagation using adaptive impedance matching

• US 7,343,138 B2
• Filed: 12/08/2003
• Issued: 03/11/2008
• Est. Priority Date: 12/08/2003
• Status: Active Grant

• Current Assignee: NETGEAR, Inc.
• Original Assignee: M/A Com
• Inventors: Bengtson, David, Douglas, Dale Scott
• Primary Examiner(s): VO, NGUYEN THANH
• Application Number:
  US10/730,725
• Publication Number:
  US 20050124303A1
• Time in Patent Office: 1,555 Days
• Field of Search: 455/103, 455/110, 455/114.1, 455/114.2, 455/127.1, 455/127.2, 455/127.3, 333/32, 330/278, 330/295
• US Class Current: 455/103
• CPC Class Codes: H03F 1/56 Modifications of input or output impedances, not otherwise provided for
• CPC Class Codes: H03F 2200/331 Sigma delta modulation being used in an amplifying circuit
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/602 Combinations of several amplifiers

Abstract

The invention relates to for processing an electromagnetic input signal, wherein the signal is passed through an input to be modified across a plurality of modifying segments using a characteristic of the signal, and wherein the plurality of segments have a plurality of states controlled by a control signal, by determining a reference impedance for the input for one or more states of the plurality of segments; and adaptively adjusting impedance of the input toward the reference impedance. This may be accomplished for example, by using a matching circuit comprising one or more selected from the group consisting of a digital signal processor, a microprocessor, a logic circuit, an integrated circuit, a phase shifter, a resistor, a variable inductor, and a variable capacitor. The matching circuit determines shifts in impedance of the input after a change in state of the segments; and adaptively adjusts the impedance based upon the shift.

Claims

1. A method for the processing of an electromagnetic input signal, wherein said signal is passed through an input to be modified across a plurality of modifying segments to generate an output signal, wherein said plurality of segments have a plurality of states controlled by a control signal that is generated from a characteristic of the input signal, said method comprising the steps of:

determining a reference impedance for said input for one or more states of said plurality of segments; and

adaptively adjusting impedance of said input toward said reference impedance;

wherein said input signal is a carrier wave modulated by a phase portion of an information signal, and said control signal is comprised from the magnitude portion of said input signal.

2. A method as in claim 1, wherein said adaptive adjustment of said impedance is accomplished by adjusting the phase of said input signal and the resistance of said input based upon said reference.

3. A method as in claim 1, wherein said adaptive adjustment of said impedance of said input is based upon a shift in impedance of said input away from said reference impedance due to a change in said state of said plurality of segments.

4. A method as in claim 1, wherein one or more of said segments is independently controlled as a power amplifier by said characteristic of said input signal to contribute power to an output signal.

5. A method as in claim 4, wherein said combining of power is accomplished using one or more selected from the group consisting of power transformers, quarter-wave transmission lines, discrete LC components, and a Pi-networks.

6. A method as in claim 1, wherein one or more of said segments is independently controlled as a current source by said characteristic of said input signal to contribute current to an output signal.

7. A method for the processing of an electromagnetic input signal, wherein said signal is passed through an input to be amplified across a plurality of amplifying segments to generate an output signal, wherein said plurality of segments have a plurality of states controlled by a control signal that is generated from a characteristic of the input signal, said method comprising the steps of:

determining any shift in impedance of said input to said plurality of segments after a change in said state of said segments; and

adaptively adjusting said impedance of said input based upon said shift;

wherein said input signal is a carrier wave modulated by a phase portion of an information signal, and said control signal is comprised from the magnitude portion of said input signal.

8. A method as in claim 7, wherein said adaptive adjustment of said impedance of said input is accomplished by determining a reference state input impedance for said input, and adjusting the phase of said input signal and the resistance of said input after each change in state back toward said reference state input impedance.

9. An apparatus for processing an electromagnetic input signal, wherein said signal is passed through an input to be modified across a plurality of modifying segments to generate an output signal, wherein said plurality of segments have a plurality of states controlled by a control signal that is generated from a characteristic of the input signal, said apparatus comprising:

a matching circuit to determine a reference impedance for said input for one or more states of said plurality of segments; and

adaptively adjust impedance of said input toward said reference impedance; and

a source of a carrier wave modulated by the phase portion of an information signal that is said electromagnetic input signal inputted into said plurality of segments, and a source for generating said control signal from a magnitude portion of said input signal.

10. The apparatus of claim 9, wherein said matching circuit comprises one or more selected from the group consisting of a digital signal processor, a microprocessor, a logic circuit, an integrated circuit, a phase shifter, a resistor, a variable inductor, and a variable capacitor.

11. The apparatus of claim 10, wherein said phase shifter comprises one or more selected from the group consisting of a digital stepped phase shifter, delay lines, waveguide elements, and microstrips.

12. The apparatus of claim 10, wherein said resistor is a digital resistor.

13. The apparatus of claim 9, wherein one or more of said segments is independently controlled as a power amplifier by said characteristic of said input signal to contribute power to an output signal.

14. The apparatus of claim 13, wherein said combining of power is accomplished using one or more selected from the group consisting of power transformers, quarter-wave transmission lines, discrete LC components, and a Pi-networks.

15. The apparatus of claim 9, wherein one or more of said segments is independently controlled as a current source by said characteristic of said input signal to contribute current to an output signal.

16. A method for the processing of an electromagnetic input signal, wherein said input signal is a carrier wave modulated by a phase portion of an information signal and wherein said input signal is passed through an input to be modified across a plurality of modifying segments to generate an output signal, the plurality of segments having a plurality of states controlled by a control signal comprising a magnitude portion of the input signal, said method comprising the steps of:

determining a reference impedance for said input for one or more states of said plurality of segments; and

adaptively adjusting impedance of said input toward said reference impedance.

17. An apparatus for processing an electromagnetic input signal, wherein said input signal is passed through an input to be modified across a plurality of modifying segments to generate an output signal, the plurality of segments having a plurality of states controlled by a control signal, said apparatus comprising:

a matching circuit for determining a reference impedance for said input for one or more states of said plurality of segments, and for adaptively adjusting an impedance of said input toward said reference impedance;

a source of a carrier wave modulated by a phase portion of an information signal that is the electromagnetic input signal inputted into the plurality of segments; and

a source for generating the control signal from a magnitude portion of the input signal.