RF Energy Recovery System

• US 20130343106A1
• Filed: 01/31/2013
• Published: 12/26/2013
• Est. Priority Date: 06/25/2012
• Status: Active Grant

• Current Assignee: ETA Devices, Inc. (Nokia Corporation)
• Original Assignee: ETA Devices, Inc. (Nokia Corporation)
• Inventors: Perreault, David J., Dawson, Joel L.
• Granted Patent: US 8,830,710 B2
• Time in Patent Office: Days
• US Class Current: 363/67
• CPC Class Codes: H02M 7/06 using discharge tubes without control electrode or semiconductor devices without control electrode
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• CPC Class Codes: H03F 1/02 Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
• CPC Class Codes: H03F 2200/06 A balun, i.e. balanced to or from unbalanced converter, being present at the input of an amplifier
• CPC Class Codes: H03F 2200/09 A balun, i.e. balanced to or from unbalanced converter, being present at the output of an amplifier
• CPC Class Codes: H03F 2200/192 A hybrid coupler being used at the input of an amplifier circuit
• CPC Class Codes: H03F 2200/204 A hybrid coupler being used at the output of an amplifier circuit
• CPC Class Codes: H03F 2200/462 the current being sensed
• CPC Class Codes: H03F 3/00 Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
• CPC Class Codes: H03F 3/195 in integrated circuits
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H03F 3/602 Combinations of several amplifiers
• CPC Class Codes: H03H 7/38 Impedance-matching networks

Abstract

An energy recovery system is provided that can be used in place of a resistive termination. The energy recovery system can simulate the behavior and performance of a resistive termination, while recovering at least some of the energy that would otherwise have been dissipated within the termination. In one embodiment, the energy recovery system includes a rectification system having a plurality of tuned rectifier circuits and an RF input network to provide input power distribution to the plurality of tuned rectifier circuits and input impedance shaping to shape the collective input impedance of the plurality of tuned rectifier circuits as seen at the RF input port of the RF input network.

Claims

1. An energy recovery system to simulate behavior of a resistive termination for a radio frequency (RF) circuit coupled to the energy recovery system, the energy recovery system comprising:

a rectification system having a plurality of tuned rectifier circuits and a plurality of rectifier input ports corresponding to the plurality of tuned rectifier circuits, the rectification system to rectify RF energy received at the plurality of rectifier input ports to generate a direct current (dc) signal at one or more rectifier output ports;

an RF input network having an RF input port and multiple RF output ports, the RF input port forming an input of the energy recovery system and the multiple RF output ports being coupled to the plurality of rectifier input ports of the rectification system, the RF input network to provide input power distribution to the plurality of tuned rectifier circuits and input impedance shaping to shape the combined input impedance of the plurality of tuned rectifier circuits as seen at the RF input port of the RF input network; and

a dc-dc converter system having an energy recovery input port and a dc output port, the energy recovery input port of the dc-dc converter system coupled to the output port of at least one rectifier to convert rectified power to a useable dc output voltage, wherein the voltage at the energy recovery input port of the dc-dc converter system is regulated.

2. The energy recovery system of claim 1, wherein:

the rectification system includes a single rectifier output port that carries a combined dc signal of the plurality of tuned rectifier circuits, the single rectifier output port being coupled to the energy recovery input port of the dc-dc converter system.

3. The energy recovery system of claim 2, wherein:

the dc-dc converter system comprises a dc-dc converter that regulates its input voltage.

4. The energy recovery system of claim 3, wherein:

the dc-dc converter is configured so that the regulated input voltage of the dc-dc converter changes based, at least in part, on an RF input power level of the rectification system.

5. The energy recovery system of claim 2, further comprising:

at least one additional RF input network and at least one additional rectification system coupled to the energy recovery input port of the dc-dc converter system.

6. The energy recovery system of claim 2, wherein:

the dc-dc converter system comprises a three-or-more port dc-dc converter that includes a first port whose voltage is regulated by the dc-dc converter and which receives an output signal of the rectification system, a second port to output recovered energy to a load device, and a third port to provide power to the dc-dc converter for use in regulating the output voltage of the second port.

7. The energy recovery system of claim 6, wherein:

the third port of the dc-dc output converter is coupled to an energy buffer for use in storing energy to regulate the output voltage of the second port.

8. The energy recovery system of claim 2, wherein:

the dc-dc converter system comprises a first dc-dc converter having an input port and an output port, the first dc-dc converter input port coupled to the single rectifier output port to convert rectified power to a useable dc output voltage at the first dc-dc converter output port; and

a second dc-dc converter having an output port coupled to an input port of the first dc-dc converter to regulate an input voltage thereof.

9. The energy recovery system of claim 8, wherein:

the first and second dc-dc converters are both switched-mode converters.

10. The energy recovery system of claim 8, wherein:

one of the first and second dc-dc converters is a linear regulator and the other of the first and second dc-dc converters is a switched-mode converter.

11. The energy recovery system of claim 1, wherein:

the rectification system includes multiple rectifier output ports that each correspond to a subgroup of the plurality of tuned rectifier circuits; and

the dc-dc converter system comprises multiple dc-dc converters having regulated input voltages coupled to the multiple rectifier output ports to receive dc signals from the multiple rectifier output ports and covert them to one or more useable dc output voltages.

12. The energy recovery system of claim 1, wherein:

the RF input network includes a resistance compression network (RCN) to compress the resistance of the combined input impedance of the plurality of tuned rectifier circuits as seen at the RF input port of the RF input network.

13. The energy recovery system of claim 12, wherein:

the resistance compression network has an order of 2 or greater.

14. The energy recovery system of claim 12, wherein:

the resistance compression network is a lossless or near lossless network.

15. The energy recovery system of claim 14, wherein:

the resistance compression network includes a pair of complementary reactances each having a terminal connected to a common potential.

16. The energy recovery system of claim 12, wherein:

the resistance compression network includes one or more transmission line sections.

17. The energy recovery system of claim 1, wherein:

the plurality of tuned rectifier circuits includes at least one tuned rectifier circuit that is tuned to provide an approximately resistive input impedance.

18. A machine implemented method for use in capturing energy output by a radio frequency (RF) circuit, the method comprising:

receiving an RF signal from the RF circuit;

distributing the RF signal among a plurality of tuned rectifier circuits, the plurality of tuned rectifier circuits to each generate a direct current (dc) signal at an output thereof in response to the RF input signal;

providing impedance shaping in coupling the input of the RF circuit to the input impedances of the plurality of tuned rectifier circuits to provide an approximately constant, resistive input impedance to the RF circuit; and

regulating an output voltage of the plurality of tuned rectifier circuits.

19. The method of claim 18, further comprising:

applying one or more dc signals output by the plurality of tuned rectifier circuits to one or more dc-dc output converters, at least one of which has a regulated input voltage, to convert the one or more dc signals to one or more useable dc output voltages.

20. The method of claim 18, wherein:

providing impedance shaping includes providing resistance compression to compress the input impedances of the plurality of tuned rectifier circuits to provide the approximately constant, resistive input impedance to the RF circuit.

21. The method of claim 18, further comprising:

combining output signals of the plurality of tuned rectifier circuits to generate a combined output signal;

delivering the combined output signal to a dc-dc output converter to convert the combined output signal to a useable dc output voltage; and

regulating an input voltage of the dc-dc output converter.

22. The method of claim 18, wherein:

distributing the RF signal among a plurality of tuned rectifier circuits includes delivering a portion of the RF signal to a first tuned rectifier circuit that is tuned to provide an approximately resistive input impedance.