Automatic impedance matching method and module, particularly for a radio-frequency transmission or reception chain

• US 10,666,219 B2
• Filed: 11/09/2015
• Issued: 05/26/2020
• Est. Priority Date: 11/13/2014
• Status: Active Grant

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: De Foucauld, Emeric
• Primary Examiner(s): Outten, Samuel S
• Application Number:
  US14/936,319
• Publication Number:
  US 20160142035A1
• Time in Patent Office: 1,660 Days
• Field of Search: 333 173
• CPC Class Codes: H01Q 1/50 Structural association of antennas with earthing switches, lead-in devices or lightning protectors
• 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
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H

Abstract

An automatic impedance matching method for a radio-frequency chain comprises: an impedance matching network having an input and an output, a first radio-frequency device connected to the input and a second radio-frequency device connected to the output, the impedance matching network exhibiting a reconfigurable topology and comprising a plurality of reactive elements, at least one of which exhibits a variable reactance, the method comprising the choice of the configuration of the impedance matching network allowing the implementation of impedance matching while minimizing losses. An automatic impedance matching module for implementing the method is provided. Radio-frequency transmission and reception chains comprising a module are also provided.

Claims

1. An automatic impedance matching module that is intended to be arranged between a first radio-frequency device and a second radio-frequency device, said module comprising:

an impedance matching network having an input that is intended to be connected to said first radio-frequency device and an output that is intended to be connected to said second radio-frequency device, said impedance matching network comprising a plurality of reactive elements, at least one of which exhibits a variable reactance;

a current and voltage measuring device, which is designed to measure a current and a voltage at the input or at the output of said impedance matching network;

at least one first configuration device for said impedance matching network, which is capable of modifying the reactance of said or of each said reactive element exhibiting a variable reactance; and

a data processor that is configured to receive, as input, current and voltage measurements from said measuring device and to provide, as output, control signals for said at least one first configuration device;

wherein;

said impedance matching network exhibits a reconfigurable topology;

the module also comprises at least one second configuration device for said impedance matching network, which is capable of modifying its topology;

said data processor is configured to;

i determine a complex impedance Zm by calculating a ratio and a phase shift between the voltage and the current that are measured by said measuring device, said complex impedance representing a load impedance of said first radio-frequency device or an input impedance of said second radio-frequency device, depending on whether said measuring device is designed to take measurements at the input or at the output of said impedance matching network;

ii from said complex impedance Zm, from the topology and from known current values of the reactive elements of said impedance matching network, calculating the value of a complex impedance Zd that is representative of an output impedance of said first radio-frequency device or of an input impedance of said second radio-frequency device, depending on whether said measuring device is designed to take measurements at the input or at the output of said impedance matching network;

iii for a plurality of possible topologies of said impedance matching network, calculating new reactance values for said at least one reactive element exhibiting a variable reactance, said calculating being performed, for each said topology, so that said load impedance of said first radio-frequency device or said input impedance of said second radio-frequency device takes a value as close as possible to a predefined nominal value;

iv choosing, from among said topologies of said impedance matching network, the one that minimizes power losses that are caused within the matching network by resistive components of the impedances of said reactive elements, when the reactance of said at least one reactive element exhibiting a variable reactance takes the calculated value of the complex impedance Zd; and

v generating control signals for said first and second configuration devices that are adapted so that said devices configure the impedance matching network so that it takes the chosen topology and so that said at least one reactive element exhibiting a variable reactance takes the calculated value of the complex impedance Zd.

2. The automatic impedance matching module of claim 1, wherein said data processor is also configured to receive, as input, an electrical power measurement, or data allowing an electrical power to be calculated, and to generate control signals for said first configuration device(s) that are adapted so that said devices iteratively adjust the reactance of said or of each said reactive element exhibiting a variable reactance so as to maximize said electrical power.

3. The automatic impedance matching module of claim 2, wherein said data processor is configured to calculate said electrical power from the current and voltage measurements from said measuring device.

4. The automatic impedance matching module of claim 2, also comprising a power measuring device that is designed to measure an output electrical power from said second radio-frequency device and to provide a measurement result for said data processor.

5. A radio-frequency transmission chain comprising a power amplifier, an antenna and an automatic impedance matching module according to claim 1 that is connected between an output of said power amplifier and an input port of said antenna.

6. A radio-frequency reception chain comprising an antenna, a low-noise amplifier and an automatic impedance matching module according to claim 1 that is connected between an output port of said antenna and an input of said low-noise amplifier.