# US 10,122,388 B2 · Auto-tunable antenna devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,122,388 B2 - Document ID: US10122388B2 - Status: Granted - Kind: B2 - Application number: 14/563,808 - Filed: 2014-12-08 - Published: 2016-06-09 - Granted: 2018-11-06 - Earliest claimed: 2014-12-08 - Assignees: Honeywell International Inc. - Applicants: Honeywell International Inc. - Inventors: Glen Backes; Doug Carlson; Robert C. Becker; Alan Cornett; Kelly Muldoon; Lisa Lust - Web page: https://patentgrep.com/patent/US10122388B2 ## CPC - H04B 1/0053: {with common antenna for more than one band} - H03J 1/0008: {using a central processing unit, e.g. a microprocessor (digital tuning in general H03J5/0245)} - H03J 7/02: Automatic frequency control (H03J7/18 takes precedence) - H03J 7/04: where the frequency control is accomplished by varying the electrical characteristics of a non-mechanically adjustable element or where the nature of the frequency controlling element is not significant - H04B 1/0458: {Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages (matching circuits in general H03H)} - H03J 2200/06: Tuning of antenna - H04B: TRANSMISSION - H03J: TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS ## Abstract Auto-tunable antenna devices and methods of using the same are described herein. One method for tuning an antenna of a device includes comparing a reference phase of a reference signal to a return phase of a return signal of the antenna and sending a correction signal to a tunable circuit element of the antenna in response to the reference phase being out of phase with the return phase. ## Claims ### Claim 1 A method for tuning an antenna of a device, comprising: determining that an antenna has performance degradation, wherein performance degradation includes a detuned antenna created by a shift to a different signal frequency than an intended signal frequency, by using a phase frequency detector to compare a reference phase of a portion of a reference signal of the antenna to a return phase of a portion of a return signal of the antenna, wherein a first directional coupler electrically connected to the antenna directs the portion of the reference signal to the phase frequency detector and a second directional coupler electrically connected to the antenna directs the portion of the return signal to the phase frequency detector and wherein a first frequency divider electrically connected between the first directional coupler and the phase frequency detector divides the reference phase of the portion of the reference signal and a second frequency divider electrically connected between the second directional coupler and the phase frequency detector divides the return phase of the portion of the return signal; and sending a correction signal, including an analog control voltage, to a tunable circuit element of the antenna in response to the reference phase being out of phase with the return phase, wherein an undivided reference phase of the portion of the reference signal and an undivided return phase of the portion of the return signal are retained by the phase frequency detector for sending the correction signal. ### Claim 2 (depends on 1) The method of claim 1, including capturing the reference signal and the return signal from a signal transmitted by the antenna of the device. ### Claim 3 (depends on 1) The method of claim 1, including identifying the reference phase is out of phase with the return phase, wherein out of phase includes exceeding a threshold value from 180 degrees out of phase. ### Claim 4 (depends on 1) The method of claim 1, including shifting one of the reference phase and the return phase 180 degrees, wherein out of phase includes exceeding a threshold value from 0degrees out of phase. ### Claim 5 (depends on 1) The method of claim 1, including amplifying at least one of the reference signal and the return signal using an amplifier. ### Claim 6 (depends on 5) The method of claim 5, including driving a resonant frequency of the antenna to tune the antenna using the analog control voltage. ### Claim 7 A device including: an antenna including a tunable circuit element, wherein the antenna has performance degradation due to the antenna being detuned by the antenna shifting to a different resonant frequency than an intended signal frequency; and a phase frequency detector to: compare a reference phase of a portion of a reference signal of the antenna to a return phase of a portion of a return signal of the antenna to determine whether performance degradation is occurring, wherein a first directional coupler electrically connected to the antenna directs the portion of the reference signal received from the antenna to the phase frequency detector and a second directional coupler electrically connected to the antenna directs the portion of the return signal to the phase frequency detector and wherein a first frequency divider electrically connected between the first directional coupler and the phase frequency detector divides the reference phase of the portion of the reference signal and a second frequency divider electrically connected between the second directional coupler and the phase frequency detector divides the return phase of the portion of the return signal; if performance degradation is occurring identify the reference phase is out of phase with the return phase; and, in response, send a correction signal, including an analog control voltage, to the tunable circuit element of the antenna, wherein an undivided reference phase of the portion of the reference signal and an undivided return phase of the portion of the return signal are retained by the phase frequency for sending the correction signal. ### Claim 8 (depends on 7) The device of claim 7, wherein the antenna includes a tunable antenna. ### Claim 9 (depends on 7) The device of claim 7, wherein an integrated resistor is 180degrees out of phase with the reference phase of the reference signal. ### Claim 10 (depends on 7) The device of claim 7, wherein the device is under microcontroller control to provide antenna tuning at specified periods of time. ### Claim 11 A device including: an antenna including a tunable circuit element, wherein the antenna has performance degradation due to the antenna being detuned by the antenna shifting to a different resonant frequency than an intended signal frequency; a phase shifter to shift at least one of a reference phase of a portion of a reference signal and a return phase of a portion of a return signal of the antenna a threshold degree; and a phase frequency detector to: compare the reference phase of the portion of the reference signal to the return phase of the portion of the return signal to determine whether performance degradation is occurring, wherein a first directional coupler electrically connected to the antenna directs the portion of the reference signal to a phase frequency detector and a second directional coupler electrically connected to the antenna directs the portion of the return signal to the phase frequency detector and wherein a first frequency divider electrically connected between the first directional coupler and the phase frequency detector divides the reference phase of the portion of the reference signal and a second frequency divider electrically connected between the second directional coupler and the phase frequency detector divides the return phase of the portion of the return signal; if performance degradation is occurring identify the reference phase is out of phase with the return phase; and, in response, send a correction signal to the tunable circuit element of the antenna; wherein the tunable circuit element applies an analog control voltage to tune the antenna of the device in response to receiving the correction signal and wherein an undivided reference phase of the portion of the reference signal and an undivided return phase of the portion of the return signal are retained by the phase frequency detector for sending the correction signal. ### Claim 12 (depends on 11) The device of claim 11, wherein the correction signal includes the analog control voltage. ### Claim 13 (depends on 11) The device of claim 11, wherein the first frequency divider divides the reference phase of the portion of the reference signal and the second frequency divider divides the return phase of the portion of the return signal to provide a frequency range that is accepted by the phase frequency detector. ### Claim 14 (depends on 11) The device of claim 11, wherein the tunable circuit element is a varactor that is under analog control by correction signal of the phase frequency detector. ### Claim 15 (depends on 11) The device of claim 11, wherein the tunable circuit element is a digitally-programmed capacitor, and the correction signal is digitized and sent to the digitally-programmed capacitor.