The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 2017
Filed:
Oct. 03, 2014
Apple Inc., Cupertino, CA (US);
Liang Han, Sunnyvale, CA (US);
Matthew A. Mow, Los Altos, CA (US);
Thomas E. Biedka, San Jose, CA (US);
Mattia Pascolini, San Francisco, CA (US);
Ming-Ju Tsai, Cupertino, CA (US);
James G. Judkins, Campbell, CA (US);
Victor Lee, Sunnyvale, CA (US);
Robert W. Schlub, Cupertino, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
An electronic device may have control circuitry that uses a reflectometer to measure antenna impedance during operation. The reflectometer may have a directional coupler that is coupled between radio-frequency transceiver circuitry and an antenna. A calibration circuit may be coupled between the directional coupler and the antenna. The calibration circuit may have a first port coupled to the antenna, a second port coupled to the directional coupler, and a third port that is coupled to a calibration resistance. The reflectometer may have terminations of identical impedance that are coupled to ground. Switching circuitry in the reflectometer may be used to route signals from the directional coupler to a feedback receiver for measurement by the control circuitry or to ground through the terminations. Calibrated antenna reflection coefficient measurements may be used in dynamically adjusting the antenna.