Regulating power duty cycle of an RF transmitter/receiver responsive to distance moved
View Patent ↗Various methods and associated wireless communication mobile terminals are provided that repetitively switch power on and off to a RF transmitter and/or to a RF transceiver, and that regulate the power duty cycle in response to movement of the associated communication terminal. Movement of the communication terminal may be sensed in response to an acceleration signal from an accelerometer, a position signal from a GPS receiver, a light level signal from an ambient light sensor, and/or a pressure level signal from a pressure sensor.
1. A method for regulating power in a wireless communication terminal, the method comprising:
repetitively switching power-on and power-off to a RF transmitter circuit and/or a RF receiver circuit;
sensing movement by the wireless communication terminal from a previous location; and
regulating the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit in response to the sensed movement, wherein:
the RF transmitter circuit is configured to encode and transmit a signal according to at least one cellular communication protocol;
the RF receiver circuit is configured to receive and decode a signal according to the at least one cellular communication protocol;
sensing movement comprises searching for signals from WLAN devices; and
regulation of the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit comprises:
increasing the power-on to power-off duty cycle in response to newly discovered signals from a WLAN device that is separate from the communication terminal; and
decreasing the power-on to power-off duty cycle in response to detecting absence of signals from the previously discovered WLAN device.
2. A method for regulating power in a wireless communication terminal, the method comprising:
repetitively switching power-on and power-off to a RF transmitter circuit and/or a RF receiver circuit;
sensing movement by the wireless communication terminal from a previous location; and
regulating the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit in response to the sensed movement, wherein:
the RF transmitter circuit is configured to encode and transmit a signal according to at least one cellular communication protocol;
the RF receiver circuit is configured to receive and decode a signal according to the at least one cellular communication protocol;
sensing movement comprises searching for signals from Bluetooth devices; and
regulation of the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit comprises:
increasing the power-on to power-off duty cycle in response to newly discovered signals from a Bluetooth device that is separate from the communication terminal; and
decreasing the power-on to power-off duty cycle in response to detecting absence of signals from the previously discovered Bluetooth device.
3. A method for regulating power in a wireless communication terminal, the method comprising:
repetitively switching power-on and power-off to a RF transmitter circuit and/or a RF receiver circuit;
sensing movement by the wireless communication terminal from a previous location; and
regulating the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit in response to the sensed movement, wherein:
the RF transmitter circuit is configured to encode and transmit a signal according to at least one cellular communication protocol;
the RF receiver circuit is configured to receive and decode a signal according to the at least one cellular communication protocol;
sensing movement comprises searching for signals from WLAN devices and/or Bluetooth devices; and
regulation of the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit comprises:
decreasing the power-on to power-off duty cycle in response to discovering signals from a WLAN device and/or a Bluetooth device that is known to be associated with a previously determined location where the communication terminal remained substantially stationary for at least a threshold time; and
increasing the power-on to power-off duty cycle in response to detecting absence of signals from the previously detected WLAN device and/or the Bluetooth device.
4. A method for regulating power in a wireless communication terminal, the method comprising:
repetitively switching power-on and power-off to a RF transmitter circuit and/or a RF receiver circuit;
sensing movement by the wireless communication terminal from a previous location; and
regulating the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit in response to the sensed movement,
wherein repetitively switching power-on and power-off to a RF transmitter circuit and/or a RF receiver circuit comprises:
maintaining the RF transmitter circuit powered-off in response to the communication terminal determining that it has moved less than a threshold distance from a previous location;
repetitively switching power-on and power-off to the RF transmitter circuit in response to the communication terminal determining that it has moved more than the threshold distance from the previous location;
maintaining the power-on to power-off duty cycle of the RF receiver circuit below a defined level in response to the communication terminal determining that it has moved less than the threshold distance from the previous location; and
maintaining the power-on to power-off duty cycle of the RF receiver circuit above the defined level in response to the communication terminal determining that it has moved more than the threshold distance from the previous location.
5. A method for regulating power in a wireless communication terminal, the method comprising:
repetitively switching power-on and power-off to a RF transmitter circuit and/or a RF receiver circuit;
sensing movement by the wireless communication terminal from a previous location;
regulating the power-on to power-off duty cycle of the RF transmitter circuit and/or the RF receiver circuit in response to the sensed movement; and
in response to the communication terminal determining that it has moved less than a threshold distance from a previous location, separately controlling the power-on to power-off duty cycle of the RF transmitter circuit relative to the RF receiver circuit to cause the RF transmitter circuit to cycle between power-on and power-off at a lower rate than the RF receiver circuit.
6. The method of claim 5 , further comprising:
in response to the communication terminal determining that it has moved less than the threshold distance from the previous location, controlling the power-on to power-off duty cycle of the RF transmitter circuit to cause the RF transmitter circuit and the RF receiver circuit to be concurrently powered-on during intervals that repeat at a defined rate.
7. The method of claim 5 , further comprising:
maintaining a cell search rate, at which the communication terminal searches for new cellular base station identifiers that are within range of the RF receiver circuit, below a threshold rate in response to the communication terminal determining that it has moved less than the threshold distance from the previous location; and
maintaining the cell search rate above the threshold rate in response to the communication terminal determining that it has moved more than the threshold distance from the previous location.
8. The method of claim 5 , further comprising:
controlling one or more repetition timing intervals for carrying out operations to monitor a paging channel, cell search operations, timing alignment operations, and/or location update operations in response to the sensed movement of the wireless communication terminal.
9. The method of claim 5 , further comprising:
controlling a number of base stations that are tracked by the wireless communication terminal in response to the sensed movement of the wireless communication terminal.
10. A wireless communication terminal comprising:
a RF transmitter circuit that is configured to transmit signals to a cellular base station;
a RF receiver circuit that is configured to receive signals from the cellular base station;
a movement sensor that is configured to sense distance moved by the wireless communication terminal from a previous location in response to an acceleration signal from an accelerometer, a position signal from a GPS receiver, a light level signal from an ambient light sensor, and/or a pressure level signal from a pressure sensor; and
a controller circuit that is configured to repetitively switch power-on and power-off to the RF transmitter and receiver circuits, to decrease the power-on to power-off duty cycle of the RF transmitter and receiver circuits in response to determining that the sensed distance is less than a threshold distance, to increase the power-on to power-off duty cycle of the RF transmitter and receiver circuits in response to determining that the sensed distance is more than the threshold distance, to separately control the power-on to power-off duty cycle of the RF transmitter circuit relative to the RF receiver circuit to cause the RF transmitter circuit to cycle between power-on and power-off at a lower rate than the RF receiver circuit and to cause the RF transmitter circuit and the RF receiver circuit to be concurrently powered-on during intervals that repeat at a defined rate while the sensed distance is less than the threshold distance.