摘要:
A proximity regulation system for use with a portable cell phone and a method of operating the same. In one embodiment, the proximity regulation system includes a location sensing subsystem that is configured to determine a location of the portable cell phone proximate a user. A power governing subsystem is coupled to the location sensing subsystem and configured to determine a proximity transmit power level of the portable cell phone based on the location.
摘要:
The present invention provides a device for connecting a power supply to a rechargeable device, in which a detection unit is adapted to detect power levels of a battery to output a first signal when a low power level of the battery is detected, and a second signal when a sufficient power level of the battery is detected. A power control unit is adapted to receive the first and second signals, and to disconnect circuitry in the rechargeable device from the battery when the first signal is asserted, and to connect the circuitry in the rechargeable device to the battery when the second signal is asserted.
摘要:
A method and apparatus are disclosed for tuning a voltage controlled oscillator (VCO) having two point modulation used in a phase lock loop modulation system. A loop correction voltage applied to a first modulation input of the VCO when a first modulation signal, e.g., +1, is applied to a second modulation input of the VCO is compared to a loop correction voltage applied to the first modulation input when a second modulation signal, e.g., −1, is applied to the second modulation input of the VCO. The comparison produces a correction signal used to adjust the signal level of at least one of the signals, e.g., the second modulation input signal, applied to the two modulation inputs of the VCO.
摘要:
Proximity regulation systems for use with a portable cell phone and portable cell phones are disclosed. In one embodiment, the portable cell phone includes: (1) an operation mode input or circuit and (2) means for determining a transmit power level of the portable cell phone based on the operation mode input or circuit.
摘要:
Proximity regulation systems for use with a portable cell phone and portable cell phones are disclosed. In one embodiment, a portable cell phone includes a proximity regulation system having a location sensing subsystem configured to determine a location of a portable cell phone proximate a user by determining a mode of operation of the portable cell phone. A power governing subsystem is coupled to the location sensing subsystem and configured to determine a proximity transmit power level of the portable cell phone based on the location.
摘要:
A data-pattern feedback mechanism is introduced into the peak detection process of an automatic frequency compensation system in a Gaussian Frequency Shift Keying (GFSK) modulated system, providing fast and accurate fine-stage automatic frequency compensation (AFC). Maximum positive and negative peak registers are updated with new values as necessary based on detection during a sequence of identical binary bit values (e.g., during a “00” for detection of maximum negative peak frequency, or during a “11” for detection of maximum positive peak frequency), in a particular data frame. As soon as an initial value is determined for both the maximum positive and negative peak frequencies (e.g., after the first occurrence of a “11” and a “00”, in any order), fine-stage automatic frequency compensation can be initiated. Subsequent adjustments to the VCO of the local oscillator will further refine the frequency offset towards the ideal of zero. Quick determination of the maximum positive and negative peak frequencies is made based on data pattern feedback in accordance with the principles of the present invention, allowing for a fast and accurate fine-stage automatic frequency compensation adjustment of a local oscillation clock signal.
摘要:
Clocks between at least two wireless devices are synchronized to reduce the need to transmit synchronization signals over a wireless communication channel therebetween. Two wireless devices synchronize their respective clocks with each other when each are electrically coupled, e.g., during a cradle time when brought into physical contact with each other through charge contacts, e.g., to recharge a remote portable unit. The charge signal appearing at the charge contacts is driven to create a time duration marked by a start transition and an end transition in the charge signal. The number of clock pulses of each of the two wireless devices during the time duration is counted, and compared to determine the difference in clock speeds of the wireless devices. The frequency of the clock of at least one of the wireless devices is adjusted to bring the difference in the clock speeds within a predetermined threshold tolerance level.
摘要:
Proximity regulation systems for use with a portable cell phone and portable cell phones are disclosed. In one embodiment, a portable cell phone includes a proximity regulation system having a location sensing subsystem configured to determine a location of a portable cell phone proximate a user by determining a mode of operation of the portable cell phone. A power governing subsystem is coupled to the location sensing subsystem and configured to determine a proximity transmit power level of the portable cell phone based on the location.
摘要:
A method and apparatus to perform a real-time drift correction of a local oscillator in a wireless device such as a cordless telephone, and/or to perform software-based frequency tracking of the local oscillator. With respect to the real-time drift correction, the remote handset periodically wakes from a sleep mode and goes into a normal link verification mode. Once in the link verification mode, the remote handset enters a time division duplexing (TDD) mode and attempts to establish a link with a base unit based on the timing of the TDD data frame. After the remote handset establishes a link with the base unit, the remote handset requests a security word from the base unit. Upon receiving the requested security word, the remote handset determines if the requested security word matches a security word of the remote handset. The remote handset implements a software frequency adjustment of its local oscillator. Once per frame, the remote handset enters a timing recovery state where the current state of the frame is compared with a previous state. When the cumulative timing slip is greater than a designated threshold, a frequency adjustment is made. The remote handset continuously adjusts its local oscillator to achieve frequency alignment within, e.g., 1 part per million (ppm). Alternatively, frequency alignment may be achieved to a specified value. Frequency feedback control may be software based to allow frequency tracking between two remote points in a communication system. In this way, the desirability of any frequency correction at particular times may be based on the accuracy of the recovered timing and data, the sensitivity of the mode of the receiving device, etc. For instance, the frequency can be finely adjusted during system acquisition, can be coarsely adjusted during data transfer, and/or can be programmed to essentially ignore or disregard a frequency offset which would otherwise be determined based on erroneously received data and/or timing (e.g., based on frame error information).
摘要:
A method and apparatus to perform a real-time drift correction of a remote handset's local oscillator in a digital cordless telephone. The remote handset begins in a standby (sniff) mode. The remote handset periodically wakes from a sleep mode and goes into a normal link verification mode. Once in the link verification mode, the remote handset enters a time division duplexing (TDD) mode and attempts to establish a link with a base unit based on the timing of the TDD data frame. After the remote handset establishes a link with the base unit, the remote handset requests a security word from the base unit. Upon receiving the requested security word, the remote handset determines if the requested security word matches a security word of the remote handset. The remote handset implements a software frequency adjustment of its local oscillator. Once per frame, the remote handset enters a timing recovery state where the current state of the frame is compared with a previous state. When the cumulative timing slip is greater than a designated threshold, a frequency adjustment is made. During this exchange of commands between the remote handset and base unit, the remote handset continuously adjusts its local oscillator to achieve frequency alignment within, e.g., 1 part per million (ppm). Alternatively, frequency alignment may be achieved to a specified value.