Patent ID: 8781420

Claim:
An electronic device, comprising: an antenna with which the electronic device transmits radio-frequency signals; phase and magnitude detector circuitry that is coupled to the antenna and that makes radio-frequency signal phase and magnitude measurements; storage and processing circuitry that determines whether an external object is adjacent to the antenna by processing the radio-frequency signal phase and magnitude measurements; and wireless circuitry that uses the antenna to transmit the radio-frequency signals at a given transmit power, wherein the storage and processing circuitry is configured to adjust the transmit power based on the radio-frequency signal phase and magnitude measurements, wherein the storage and processing circuitry is further configured to reduce the transmit power in response to determining that the external object is adjacent to the antenna by processing the radio-frequency signal phase and magnitude measurements, wherein the antenna is included in a plurality of antennas that are operable to transmit the radio-frequency signals, wherein the phase and magnitude detector circuitry is coupled to each of the plurality of antennas, wherein the storage and processing circuitry determines for each antenna whether the external object is adjacent to that antenna, and wherein the storage and processing circuitry is configured to temporarily disable a given antenna of the plurality of antennas in response to determining that the external object is adjacent to the given antenna.