Abstract: A wearable wireless device includes a wireless transceiver coupled to a first antenna, an energy harvester coupled to a second antenna, and a supercapacitor coupled to the energy harvester. The wireless transceiver may be configured to receive a first wireless signal from a paired wireless communication device via the first antenna. The energy harvester may be configured to convert radio-frequency (RF) energy received by the second antenna into a charge. In some instances, the energy harvester may be further configured to charge the supercapacitor in response to a presence of the RF energy. The supercapacitor may be configured to store the charge converted by the energy harvester and provide power to the wireless transceiver. In some instances, the supercapacitor may be further configured to power one or more electronic components of the wearable wireless device with the stored charge.

Abstract: This disclosure provides a method and apparatus for saving and restoring state information of a wireless device with varying amounts of available power, such as wireless devices that may harvest power from radio-frequency signals. The wireless device may save and restore varying amounts of state information based at least in part on the amount of power available. In some embodiments, some of the stored state information may be lost as the available power decreases.

Abstract: This disclosure provides a method and apparatus for a staged wake-up of a wireless device. The wireless device may include a wireless wake-up receiver and a communication transceiver. The wireless device may begin operations in a low-power mode. The wireless wake-up receiver may identify radio-frequency (RF) activity and transition operation of the wireless device from the low-power mode to an active power mode when RF activity is identified. In some implementations, RF activity is identified when an energy pattern of a received RF signal is matched to an energy pattern associated with a known communication protocol.

Abstract: This disclosure provides an active envelope detector to generate an output voltage based on an input radio-frequency (RF) signal. The active envelope detector includes a plurality of transistors configured to operate in a sub-threshold mode and generate an output voltage based on the input RF signal. A delta-modulation analog-to-digital converter (ADC) and a sigma-delta modulation ADC are provided. Both ADCs include an implementation of the active envelope detector to receive input RF signals.

Abstract: This disclosure provides a method and apparatus for saving and restoring state information of a wireless device with varying amounts of available power, such as wireless devices that may harvest power from radio-frequency signals. The wireless device may save and restore varying amounts of state information based at least in part on the amount of power available. In some embodiments, some of the stored state information may be lost as the available power decreases.

Abstract: This disclosure provides an active envelope detector to generate an output voltage based on an input radio-frequency (RF) signal. The active envelope detector includes a plurality of transistors configured to operate in a sub-threshold mode and generate an output voltage based on the input RF signal. A delta-modulation analog-to-digital converter (ADC) and a sigma-delta modulation ADC are provided. Both ADCs include an implementation of the active envelope detector to receive input RF signals.

Abstract: This disclosure provides a method and apparatus for a staged wake-up of a wireless device. The wireless device may include a wireless wake-up receiver and a communication transceiver. The wireless device may begin operations in a low-power mode. The wireless wake-up receiver may identify radio-frequency (RF) activity and transition operation of the wireless device from the low-power mode to an active power mode when RF activity is identified. In some implementations, RF activity is identified when an energy pattern of a received RF signal is matched to an energy pattern associated with a known communication protocol.

Abstract: A personal identification device may conserve power by delegating one or more operations to another device. For example, the one or more operations may be associated with the authentication of the personal identification device. In one example, the personal identification device may determine an amount of power greater than a power threshold will be consumed by the personal identification device to perform the one or more operations. The personal identification device may determine it can communicate with a mobile device that is capable of performing the one or more operations, and may then delegate the one or more operations to the mobile device to conserve power. In one example, the personal identification device may receive the results of the one or more operations from the mobile device, and may provide data associated with the results to a personal identification device detector for authentication of the personal identification device.

Abstract: Methods, systems, and devices are described for power conservation in a wireless communications system. In embodiments, power conservation may be achieved by adaptively controlling power modes of a wireless communication device, using a modulation and coding scheme (MCS) value as a factor for guidance. According to one aspect, the device may be in a reception mode. While in a first power mode, the device may receive control information for incoming data that is being transmitted via a transmission frame. The control information may be located in a first portion of the frame with the data following in a second portion of the frame. The control information may include or otherwise indicate an MCS value corresponding to the MCS applied to the incoming data. Based on the MCS value, the device may be adaptively switched to a second power mode for receiving the incoming data.

Abstract: Methods, systems, and devices are described for power conservation in a wireless communications system. In embodiments, power conservation may be achieved by adaptively controlling power modes of a wireless communication device, and implementing lower power modes with various modes of the device. According to one aspect, the mode of the device may be a beacon monitoring mode or a delivery traffic indication message (DTIM) mode. In such a mode, the device may receive a portion of a beacon in a first power mode. The device may transition to a second, different (e.g., higher) power mode using information contained in the received portion of the beacon as guidance.

Abstract: A system and method are disclosed that may allow a STA to request one or more non-associated APs to initiate channel sounding operations with the STA. In response to the request, a number of the non-associated APs may send one or more NDPs to the STA. The STA may use the received NDPs to determine a goodput value for each of the number of non-associated APs. The STA may then use the determined goodput values to select one of the number of non-associated APs with which to associate. Thereafter, the STA may initiate an association operation with the selected AP.

Abstract: A personal identification device may conserve power by delegating one or more operations to another device. For example, the one or more operations may be associated with the authentication of the personal identification device. In one example, the personal identification device may determine an amount of power greater than a power threshold will be consumed by the personal identification device to perform the one or more operations. The personal identification device may determine it can communicate with a mobile device that is capable of performing the one or more operations, and may then delegate the one or more operations to the mobile device to conserve power. In one example, the personal identification device may receive the results of the one or more operations from the mobile device, and may provide data associated with the results to a personal identification device detector for authentication of the personal identification device.

Abstract: A beacon message is wirelessly transmitted from a first device. The first device receives a first response to the beacon message, wherein the first response includes identification values associated with a personal identification device. A second device associated with the personal identification device is communicated with. The personal identification device is authenticated based, at least in part, on the identification values and the communication with the second device.

Abstract: A system and method are disclosed that may allow a STA to request one or more non-associated APs to initiate channel sounding operations with the STA. In response to the request, a number of the non-associated APs may send one or more NDPs to the STA. The STA may use the received NDPs to determine a goodput value for each of the number of non-associated APs. The STA may then use the determined goodput values to select one of the number of non-associated APs with which to associate. Thereafter, the STA may initiate an association operation with the selected AP.

Abstract: Methods, systems, and devices are described for power conservation in a wireless communications system. In embodiments, power conservation may be achieved by adaptively controlling power modes of a wireless communication device, using a modulation and coding scheme (MCS) value as a factor for guidance. According to one aspect, the device may be in a reception mode. While in a first power mode, the device may receive control information for incoming data that is being transmitted via a transmission frame. The control information may be located in a first portion of the frame with the data following in a second portion of the frame. The control information may include or otherwise indicate an MCS value corresponding to the MCS applied to the incoming data. Based on the MCS value, the device may be adaptively switched to a second power mode for receiving the incoming data.

Abstract: Methods, systems, and devices are described for power conservation in a wireless communications system. In embodiments, power conservation may be achieved by adaptively controlling power modes of a wireless communication device, and implementing lower power modes with various modes of the device. According to one aspect, the mode of the device may be a beacon monitoring mode or a delivery traffic indication message (DTIM) mode. In such a mode, the device may receive a portion of a beacon in a first power mode. The device may transition to a second, different (e.g., higher) power mode using information contained in the received portion of the beacon as guidance.

Abstract: A digital fractional PLL introduces an accumulated phase offset before the digital VCO to achieve the fractional part of the division ratio. To provide this phase offset, the digital accumulator can integrate a fractional component ?n. By forcing ?n to zero, the PLL becomes an integer-N PLL. A de-skew timing configuration can be used to remove any time mismatch between integer and fractional counters of the PLL. A digital PLL can merge the function of frequency generation (DVCO) and that of fractional frequency counting into the same circuit block by reusing various phases of the frequency output to generate a fractional frequency count. A digital integer PLL can include a comparator, wherein the feedback loop of this PLL forces the phase difference between the reference clock and feedback signals to approach zero. By changing the duty cycle of feedback signal, the frequency tracking behavior of the loop can be varied.

Abstract: A beacon message is wirelessly transmitted from a first device. The first device receives a first response to the beacon message, wherein the first response includes identification values associated with a personal identification device. A second device associated with the personal identification device is communicated with. The personal identification device is authenticated based, at least in part, on the identification values and the communication with the second device.

Abstract: The present invention aims at eliminating the effects of frequency offsets between two transceivers by adjusting frequencies used during transmission. In this invention, methods for correcting the carrier frequency and the sampling frequency during transmission are provided, including both digital and analog implementations of such methods. The receiver determines the relative frequency offset between the transmitter and the receiver, and uses this information to correct this offset when the receiver transmits its data to the original transmitter in the return path, so that the signal received by the original transmitter is in sampling and carrier frequency lock with the original transmitter's local frequency reference.

Abstract: Various methods and corresponding active interference cancellation units are described. These methods and units can perform active interference cancellation in a system including multiple radios. Notably, signals from a first radio can be received as interference at a second radio. The described methods and units can provide interference conditioning, which manipulates an interference reference of the interference at the first radio to approximate an interference observed at the second radio. After tuning of the interference conditioning, the interference can be removed.