US 11,909,427 B2 · Impedance matching

Abstract

A circuit device includes a directional coupler with a first port receiving a radiofrequency signal, a second port outputting a signal in response to signal received by the first port, and a third port outputting a signal in response to a reflection of the signal at the second port. An impedance matching network is connected between the second port and an antenna. The impedance matching network includes fixed inductive and capacitive components and a single variable inductive or capacitive component. A diode coupled to the third port of the coupler generates a voltage at a measurement terminal which is processed in order to select and set the inductance or capacitance value of the variable inductive or capacitive component.

Claims23

Dependent claims

A method for determining an inductance or capacitance value of a variable component within an impedance matching network comprising a plurality of fixed components having fixed inductance and capacitance values and said variable component having a variable inductance or capacitance value, comprising:

determining inductance and capacitance values of the fixed components so that a normalized impedance after an impedance mismatch caused by presence of a proximate conductive element belongs to an area in a Smith chart determined by all inductance or capacitance values of the variable component;
and then:
a) selecting an initial inductance or capacitance value of the variable component and obtaining a measurement of a voltage indicative of power of a reflected signal received by said impedance matching network;
and
b) changing the inductance or capacitance value of the variable component in a determined scanning direction and obtaining a further measurement of the voltage indicative of power of the reflected signal;
wherein step b) is repeated until said further measured voltage is strictly greater than a penultimately obtained measurement of the voltage indicative of power of the reflected signal.

3 more elements

determining inductance and capacitance values of the fixed components so that a normalized impedance after an impedance mismatch caused by presence of a proximate conductive element belongs to an area in a Smith chart determined by all inductance or capacitance values of the variable component and then:
a) selecting an initial inductance or capacitance value of the variable component and obtaining a measurement of a voltage indicative of power of a reflected signal received by said impedance matching network;
b) changing the inductance or capacitance value of the variable component in a determined scanning direction and obtaining a further measurement of the voltage indicative of power of the reflected signal;
and
c) repeating step b) until a minimal of the voltage indicative of power of the reflected signal is detected.

2 more elements

Dependencies are inferred from the claim text.

Impedance matching

Life of this patent

Impedance matching

Life of this patent

Abstract

Claims23