Asymmetric multilevel outphasing architecture for RF amplifiers

• US 8,164,384 B2
• Filed: 05/12/2011
• Issued: 04/24/2012
• Est. Priority Date: 11/11/2008
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Dawson, Joel L., Perreault, David J., Chung, SungWon, Godoy, Philip, Huang, Everest
• Primary Examiner(s): NGUYEN, KHANH V
• Application Number:
  US13/106,195
• Publication Number:
  US 20110215866A1
• Time in Patent Office: 348 Days
• Field of Search: 330/51, 330/124.R, 330/295
• US Class Current: 330/124.R
• CPC Class Codes: H03F 1/0244 Stepped control
• CPC Class Codes: H03F 1/0277 Selecting one or more amplifiers from a plurality of amplifiers
• CPC Class Codes: H03F 1/0294 using vector summing of two or more constant amplitude phase-modulated signals
• CPC Class Codes: H03F 2200/516 Some amplifier stages of an amplifier use supply voltages of different value
• CPC Class Codes: H03F 3/217 Class D power amplifiers; Switching amplifiers
• CPC Class Codes: H03F 3/2176 Class E amplifiers
• CPC Class Codes: H03F 3/602 Combinations of several amplifiers

Abstract

A radio frequency (RF) circuit includes a power supply configured to generate a plurality of voltages, a plurality of power amplifiers, each having an RF output port and a power supply input port, a switch network having a plurality of input ports coupled to the power supply and a plurality of switch network output ports coupled to the power supply input ports of the plurality of power amplifiers, wherein the switch network is configured to output selected ones of the plurality of voltages from the plurality of switch network output ports, at least two of the switch network output port voltages capable of being different ones of the plurality of voltages, and an RF power combiner circuit having a plurality of input ports coupled to RF output ports of the plurality of power amplifiers and an output port at which is provided an output signal of the RF circuit.

Claims

1. A radio frequency (RF) circuit comprising:

a plurality of RF amplifiers, each of the plurality of RF amplifiers having an RF output and a power supply input;

voltage providing means for providing a plurality of voltages;

means for coupling selected ones of the plurality of voltages provided by said voltage providing means to respective ones of the power supply inputs of the plurality of RF amplifiers, at least two of the outputted voltages capable of being different ones of the plurality of voltages; and

means for combining, having a plurality of input ports with each of the plurality of input ports coupled to a respective one of the output ports of said plurality of RF amplifiers, said means for combining configured to receive RF input signals from each of the plurality of RF amplifiers and for combining RF input signals provided thereto and for providing an RF output signal at an output thereof.

2. The RF circuit of claim 1 wherein:

said voltage providing means comprises a power supply to generate the plurality of voltages; and

said means for coupling selected ones of the plurality of voltages corresponds to a switch network.

3. The RF circuit of claim 1 wherein each of the power amplifiers has an RF input port and further comprises means for controlling an output signal of the RF circuit by adjusting phases of the signals received at the RF input ports and dynamically selecting the ones of the plurality of voltages outputted to each of the power amplifiers.

4. The RF circuit of claim 1 further comprising means for decreasing a difference between a sum of the powers outputted by the plurality of RF amplifiers and an RF power outputted at the output port of the RF circuit.

5. The RF circuit of claim 1 wherein said means for combining comprises means for isolating each of the plurality of input ports.

6. The RF circuit of claim 1 wherein said means for combining comprises:

at least one resistance compression network; and

at least one rectification circuit coupled to the at least one resistance compression network.

7. A radio frequency (RF) circuit comprising:

a power supply configured to generate a plurality of voltages;

a switch network having a plurality of input ports coupled to the power supply and a plurality of switch network output ports;

a plurality of RF amplifiers, each having an RF output port and a power supply input port coupled to a corresponding one of the plurality of switch network output ports, wherein each of the RF amplifiers has an RF input port configured to receive a phase adjusted signal and the switching circuit is configured to receive at least one control signal, wherein the phase adjusted signals and the at least one switching circuit control signal are used to control the output signal of the RF circuit.

8. The RF circuit of claim 7 wherein the switch network is configured to output selected ones of the plurality of voltages from the plurality of switch network output ports, at least two of the switch network output port voltages capable of being different ones of the plurality of voltages.

9. The RF circuit of claim 7 further comprising an RF combiner circuit having a plurality of input ports coupled to RF output ports of the plurality of RF amplifiers and an output port at which is provided an output signal of the RF circuit.

10. The RF circuit of claim 9, wherein the power combiner circuit further comprises:

a resistance compression network; and

a rectification circuit coupled to the resistance compression network.

11. The RF circuit of claim 7 further comprising a control system configured to provide the phase-adjusted signals over a plurality of first output ports coupled to the RF input ports of the plurality of RF amplifiers and the plurality of control signals over a plurality of second output ports coupled to the switch network.

12. The RF circuit of claim 11, wherein the control system is further configured to decrease a difference between a total of the power output from the plurality of power amplifiers and a power output from the RF circuit.