Abstract: The control of an antenna tuner for a portable electronic device includes closed loop tuning when sufficient transmit power is present. The closed loop tuning commences using a predetermined antenna tuner configuration for an operational band and device state. The closed loop tuning may be constrained by a tuning range associated with the predetermined antenna tuner configuration for the operational band and device state. Also, when transmit power is low or when a transceiver is in a receive only state, open loop tuning may be conducted by placing the antenna tuner in the predetermined (or default) configuration for the operational band and phone state.

Abstract: Communications circuitry includes a controlled antenna tuner. The voltage across elements of the antenna tuner may be determined and, if an over-voltage situation is detected, remedial action may be taken. At times when a configuration of the antenna tuner is to be maintained and an over-voltage condition exists, the remedial action may include lowering an output power from a transceiver. Another type of remedial action may include introducing a phase shift between an antenna and the antenna tuner. At times when a configuration of the antenna tuner is to be changed and an over-voltage condition exists, the remedial action may include reducing output power of the transceiver. Another type of remedial action may include waiting for an opportune time to change the antenna tuner configuration.

Abstract: The control of an antenna tuner for a portable electronic device includes closed loop tuning when sufficient transmit power is present. The closed loop tuning commences using a predetermined antenna tuner configuration for an operational band and device state. The closed loop tuning may be constrained by a tuning range associated with the predetermined antenna tuner configuration for the operational band and device state. Also, when transmit power is low or when a transceiver is in a receive only state, open loop tuning may be conducted by placing the antenna tuner in the predetermined (or default) configuration for the operational band and phone state.