Apparatus and method for controlling impedance tuning by using hybrid control algorithm

Patent metadata

Field	Value
Publication number	US-9654059-B2
Application number	US-201514854054-A
Country	US
Kind code	B2
Filing date	Sep 15, 2015
Priority date	Oct 30, 2014
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

An impedance tuning control apparatus has a processing circuit and an output circuit. The processing circuit determines a first control setting according to a first performance metric, and performs a search operation with a search start point set by the first control setting to find a second control setting according to a second performance metric. The second performance metric is different from the first performance metric. The output circuit outputs a final control setting to a tuner, wherein the final control setting is derived from the second control setting.

First claim

What is claimed is:

1. An impedance tuning control apparatus, comprising:
a processing circuit, configured to refer to first performance metrics of a plurality of candidate control settings to select a first control setting from the candidate control settings, and perform a search operation with a search start point set by the first control setting to find a second control setting according to a second performance metric different from the first performance metric; and
an output circuit, configured to output a final control setting to a tuner, wherein the final control setting is derived from the second control setting;
wherein the processing circuit is further configured to generate a pre-defined control setting to the tuner via the output circuit, and perform antenna estimation to determine a reflection coefficient involved in determining the first control setting when the tuner is configured by the pre-defined control setting.

2. The impedance tuning control apparatus of claim 1 , wherein the first performance metric includes a transducer gain or a relative transducer gain.

3. The impedance tuning control apparatus of claim 1 , wherein the processing circuit determines the first control setting by performing analytical computation based on the first performance metric.

4. The impedance tuning control apparatus of claim 1 , wherein the second performance metric includes a voltage standing wave ratio (VSWR) or a reflection coefficient amplitude/phase.

5. The impedance tuning control apparatus of claim 1 , wherein the search operation is a local minimum search operation.

6. The impedance tuning control apparatus of claim 1 , wherein the processing circuit is further configured to perform antenna estimation to determine a measured reflection coefficient, and generate an estimated reflection coefficient involved in determining the first control setting by compensating the measured reflection coefficient according to at least one factor of at least one module between an antenna and a detector input.

7. The impedance tuning control apparatus of claim 1 , wherein at least one tunable element in the tuner is configured to have a smallest element value in response to the pre-defined control setting.

8. The impedance tuning control apparatus of claim 1 , wherein each control setting includes at least a control word of a corresponding tunable element in the tuner; and when the control word in the first control setting is set by a boundary value, each candidate control setting checked by the search operation has the control word fixed at the boundary value.

9. The impedance tuning control apparatus of claim 1 , wherein the processing circuit is further configured to pre-compute at least one control setting with respect to at least one loading and at least one frequency, where the at least one control setting is determined according to the first performance metric; and the processing circuit is further configured to load the first control setting from the at least one control setting.

10. The impedance tuning control apparatus of claim 1 , wherein the processing circuit is configured to perform a coarse search operation to find a third control setting according to the first performance metric, and performs a fine search operation through a candidate control setting around the third control setting to find the first control setting according to the first performance metric; a second step size used by the fine search operation is smaller than a first step size used by the coarse search operation.

11. The impedance tuning control apparatus of claim 10 , wherein each control setting includes at least a control word of a corresponding tunable element in the tuner; and when the control word in the third control setting is set by a boundary value, each candidate control setting checked by the fine search operation has the control word fixed at the boundary value.

12. An impedance tuning control apparatus, comprising:
a processing circuit, configured to refer to first performance metrics of a plurality of candidate control settings to select a first control setting from the candidate control settings, and perform a search operation with a search start point set by the first control setting to find a second control setting according to a second performance metric different from the first performance metric; and
an output circuit, configured to output a final control setting to a tuner, wherein the final control setting is derived from the second control setting;
wherein a candidate control setting previously checked by the search operation under a loading makes the second performance metric have a metric value beyond a predetermined range, and the processing circuit is further configured to generate a search list of candidate control settings corresponding to the loading by pruning away the candidate control setting in the search list.

13. An impedance tuning control apparatus, comprising:
a processing circuit, configured to refer to first performance metrics of a plurality of candidate control settings to select a first control setting from the candidate control settings, and perform a search operation with a search start point set by the first control setting to find a second control setting according to a second performance metric different from the first performance metric; and
an output circuit, configured to output a final control setting to a tuner, wherein the final control setting is derived from the second control setting;
wherein a candidate control setting previously checked by the search operation under a loading makes the second performance metric have a metric value beyond a predetermined range, and the processing circuit is further configured to dynamically maintain a list of unfavorable control settings corresponding to the loading by adding the candidate control setting to the list of unfavorable control settings, and refer to the list of unfavorable control settings to block the candidate control setting from being checked again under the loading.

14. An impedance tuning control apparatus, comprising:
a processing circuit, configured to refer to first performance metrics of a plurality of candidate control settings to select a first control setting from the candidate control settings, and perform a search operation with a search start point set by the first control setting to find a second control setting according to a second performance metric different from the first performance metric; and
an output circuit, configured to output a final control setting to a tuner, wherein the final control setting is derived from the second control setting;
wherein the processing circuit is further configured to estimate a source impedance when the tuner is configured by the second control setting, determine a third control setting according to the first performance metric and a source impedance estimation result, and perform another search operation with a search start point set by the third control setting to find the final control setting according to the second performance metric.

15. An impedance tuning control method, comprising:
referring to first performance metrics of a plurality of candidate control settings to select a first control setting from the candidate control settings;
performing a search operation with a search start point set by the first control setting to find a second control setting according to a second performance metric different from the first performance metric;
controlling a tuner based on a final control setting derived from the second control setting; and
generating a pre-defined control setting t

Assignees

• Mediatek Inc

Inventors

• Kuo Ting-Hsuan
• Zhou Qiang
• Wu Ming-Chou
• Liang Paul Cheng Po
• Tenbroek Bernard Mark

Classifications

• H03F1/56 Primary

  Modifications of input or output impedances, not otherwise provided for · CPC title

• H03F3/19

  with semiconductor devices only · CPC title

• H03F2200/222

  A circuit being added at the input of an amplifier to adapt the input impedance of the amplifier · CPC title

• H04B1/0458

  Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages (matching circuits in general H03H) · CPC title

• H03F2200/294

  the amplifier being a low noise amplifier [LNA] · CPC title