Dynamically adjustable antennas for wearable devices

A method of operating a wearable electronic device having a display formed at a front face of the electronic device, a dielectric rear housing wall formed at a rear face of the electronic device, an antenna, and processing circuitry, the method comprising:

• with the antenna, receiving radio-frequency signals from external equipment through the dielectric rear housing wall;
• with the processing circuitry, gathering information on an amount of loading of the antenna by an external object through the dielectric rear housing wall, wherein the information comprises Received Signal Strength Indicator (RSSI) values associated with the radio-frequency signals received from the external equipment through the dielectric rear housing wall;
• and
• with the processing circuitry, adjusting the antenna to compensate for a change in the amount of loading of the antenna by the external object through the dielectric rear housing wall based on the gathered RSSI values, wherein gathering the information on the amount of loading of the antenna comprises storing acquisition times associated with each of the gathered RSSI values and storing wearable electronic device acquisition positions associated with each of the gathered RSSI values.

A method of operating a wearable electronic device having a display formed at a front face of the electronic device, a dielectric rear housing wall formed at a rear face of the electronic device, an antenna, and processing circuitry, the method comprising:

• with the antenna, receiving radio-frequency signals from external equipment through the dielectric rear housing wall;
• with the processing circuitry, gathering information on an amount of loading of the antenna by an external object through the dielectric rear housing wall;
• and
• with the processing circuitry, adjusting the antenna to compensate for a change in the amount of loading of the antenna by the external object through the dielectric rear housing wall, wherein gathering the information on the amount of loading comprises gathering phase and magnitude measurements of an impedance of the antenna based on radio-frequency signals that are transmitted to the antenna by radio-frequency transmitter circuitry on the wearable electronic device, and adjusting the antenna to compensate for the change in the amount of loading of the antenna by the external object through the dielectric rear housing wall comprises adjusting the antenna based on the gathered phase and magnitude measurements of the impedance of the antenna.

A wearable electronic device having opposing front and rear faces, the wearable electronic device comprising:

• a dielectric rear housing wall that forms the rear face of the electronic device;
• a display having a display cover layer that forms the front face of the electronic device;
• an antenna resonating element formed from conductive traces overlapping the dielectric rear housing wall, wherein the antenna resonating element is subject to loading by external objects through the dielectric rear housing wall;
• radio-frequency transceiver circuitry that is configured to transmit and receive radio-frequency signals through the dielectric rear housing wall using the antenna resonating element;
• impedance matching circuitry coupled between the antenna resonating element and the radio-frequency transceiver circuitry;
• and
• storage and processing circuitry that is configured to adjust the impedance matching circuitry in response to detecting a change in the loading of the antenna resonating element through the dielectric rear housing wall.

A method of operating a wearable electronic device having a display formed at a front face of the electronic device, a dielectric rear housing wall formed at a rear face of the electronic device, an antenna, impedance matching circuitry coupled to the antenna, and processing circuitry, the method comprising:

• with the antenna, receiving radio-frequency signals from external equipment through the dielectric rear housing wall;
• with the processing circuitry, gathering and storing Received Signal Strength Indicator (RSSI) values and corresponding RSSI acquisition times based on the received radio-frequency signals;
• with the processing circuitry, accumulating user statistics associated with operation of the wearable electronic device by a user over time;
• with the processing circuitry, processing the accumulated user statistics, the stored RSSI values, and the stored RSSI acquisition times to detect a trigger event;
• and
• with the processing circuitry, in response to detecting the trigger event, adjusting the impedance matching circuitry.