Abstract: Multiple calibration results for calibrating a barometric pressure sensor based on data received from a device containing the sensor are determined and stored in a table. The table is updated based on rules regarding a relationship between each calibration result and a current calibration value. The calibration results are weighted and combined to determine a combined calibration result. The calibration value for calibrating the sensor is selected from the calibration results, the combined calibration results, or the current calibration value based on a selection criteria.

Abstract: Determining contexts of mobile devices. Particular embodiments described herein include machines that determine two estimated positions of a mobile device that respectively correspond to first and second locations at first and second times, acquire sets of terrain or structural information for first and second areas that respectively include the first and second estimated positions, use the acquired sets of information and the estimated positions to determine if the mobile device was near or within a structure at the first and second times, determine one or more values that are indicative of vertical movement by the mobile device during a period of time between the first time and the second time, compare the one or more values to one or more threshold conditions, and determine a context of the mobile device based on the comparison.

Abstract: A method including, at a camera, detecting motion in a field of view of the camera using a motion sensor, initiating processing of video data corresponding to the field of view in which the motion was detected, ceasing the processing after a first time duration, and determining a cool-off period for the motion sensor, the cool-off period having a second time duration based on the first time duration during which the camera does not detect motion using the motion sensor.

Abstract: A battery pack includes a battery, a first temperature sensor configured to provide a first temperature value associated with a temperature of the battery, a heat source disposed proximate to the battery and configured to heat the battery, a second temperature sensor configured to provide a second temperature value associated with a temperature of the heat source, and a control board coupled to the first temperature sensor and the second temperature sensor, wherein the control board is configured to receive the first temperature value and the second temperature value. The control board is configured to compare the first temperature value and the second temperature value to determine a temperature gradient between the battery and the heat source and transmit an alert if the temperature gradient exceeds a first temperature gradient threshold.

Abstract: A method involves determining, at a mobile device or a service, an uncertainty in height above a reference altitude, an estimated 2D position of the mobile device, and an uncertainty in terrain height above the reference altitude using the estimated 2D position. An uncertainty in height above terrain, of the mobile device, is determined at the mobile device or a server using the uncertainty in height above the reference altitude and the uncertainty in terrain height above the reference altitude.

Abstract: A wholistic activity context is used to determine whether to calibrate a barometric pressure sensor of a mobile device. A pair of activity transitions are determined from three activities of the mobile device. A time relationship and a position relationship between the activity transitions is determined. An opportunity to calibrate the barometric pressure sensor occurs between the activity transitions. A calibration of the barometric pressure sensor is performed in response to determining that the time relationship and the position relationship indicate that the wholistic activity context surrounding the opportunity to calibrate the barometric pressure sensor is conducive to calibration.

Abstract: A battery pack includes a battery, a first temperature sensor configured to provide a first temperature value associated with a temperature of the battery, a heat source disposed proximate to the battery and configured to heat the battery, a second temperature sensor configured to provide a second temperature value associated with a temperature of the heat source, and a control board coupled to the first temperature sensor and the second temperature sensor, wherein the control board is configured to receive the first temperature value and the second temperature value. The control board is configured to compare the first temperature value and the second temperature value to determine a temperature gradient between the battery and the heat source and transmit an alert if the temperature gradient exceeds a first temperature gradient threshold.

Abstract: Calibrating a pressure sensor of a mobile device includes determining a first plurality of calibration values for a first plurality of visits to a first revisit zone to which a mobile device repeatedly returns; determining a first relative calibration adjustment value based on the first plurality of calibration values; determining an adjusted absolute calibration value based on i) an absolute calibration value used to calibrate pressure measurements made by a pressure sensor of the mobile device, and ii) the first relative calibration adjustment value; and calibrating pressure measurements made by the pressure sensor of the mobile device using the adjusted absolute calibration value.

Abstract: A smart-home device may include a main power rail that provides power to components of the smart-home device; an integrator coupled to the main power rail that stores energy on an energy-storage device, where the energy stored on the energy-storage device is representative of an amount an amount of power provided to the smart-home device through the main power rail during an integration cycle of the integrator; and a counter that stores a number of integration cycles performed by the integrator during a time interval, where a total amount of power provided to the smart-home device through the main power rail during the time interval is represented by: (1) the number of integration cycles performed by the integrator during the time interval; and (2) the energy stored on the energy-storage device.

Abstract: Using a pressure sensor of a mobile device to improve the accuracy of determined contexts. Particular embodiments described herein include machines that determine a context of a mobile device, and determine if the determined context is accurate using multiple measurements of pressure from a pressure sensor of the mobile device.

Abstract: A method to identify a problematic 2D position of a mobile device can include: determining a reported 2D position of the mobile device; determining a piece of information about the mobile device; and comparing the reported 2D position and the piece of information about the mobile device. Upon determining that the reported 2D position and the piece of information about the mobile device are consistent with each other, the reported 2D position of the mobile device is used as an estimate of the actual 2D position of the mobile device, or upon determining that the reported 2D position and the piece of information about the mobile device are not consistent with each other, the reported 2D position is determined to be problematic, and the reported 2D position of the mobile device is removed from a list of reported 2D positions of the mobile device.

Abstract: A method includes a mobile device receiving a plurality of first signals from one or more first transmitters in a network. Each first signal has first data including an associated time that is non-synchronized to the time of another first signal of the plurality of first signals. One or more processors synchronizes the associated time of each first signal to a common time scale. One or more processors determines a position of the mobile device using a common time scale of the plurality of first signals.

Abstract: Multiple calibration results for calibrating a barometric pressure sensor based on data received from a device containing the sensor are determined and stored in a table. The table is updated based on rules regarding a relationship between each calibration result and a current calibration value. The calibration results are weighted and combined to determine a combined calibration result. The calibration value for calibrating the sensor is selected from the calibration results, the combined calibration results, or the current calibration value based on a selection criteria.

Abstract: A smart-home device may include a main power rail that provides power to components of the smart-home device; an integrator coupled to the main power rail that stores energy on an energy-storage device, where the energy stored on the energy-storage device is representative of an amount an amount of power provided to the smart-home device through the main power rail during an integration cycle of the integrator; and a counter that stores a number of integration cycles performed by the integrator during a time interval, where a total amount of power provided to the smart-home device through the main power rail during the time interval is represented by: (1) the number of integration cycles performed by the integrator during the time interval; and (2) the energy stored on the energy-storage device.

Abstract: Multiple calibration results for calibrating a barometric pressure sensor based on data received from a device containing the sensor are determined and stored in a table. The table is updated based on rules regarding a relationship between each calibration result and a current calibration value. The calibration results are weighted and combined to determine a combined calibration result. The calibration value for calibrating the sensor is selected from the calibration results, the combined calibration results, or the current calibration value based on a selection criteria.

Abstract: A method involves selecting a set of altitude envelope distribution constraints for a building and generating a set of altitude envelope distributions for the building in accordance with the constraints. Each altitude envelope distribution includes one or more first altitude envelopes. An aggregate altitude envelope distribution is generated for the building using the set of altitude envelope distributions and in accordance with the constraints. The aggregate altitude envelope distribution includes one or more second altitude envelopes. A reference altitude of the building is determined, and an absolute aggregate altitude envelope distribution is determined using the reference altitude and the aggregate altitude envelope distribution. The aggregate altitude envelope distribution includes one or more third altitude envelopes, each corresponding to a respective estimated floor number of the building.

Abstract: Calibrating a pressure sensor of a mobile device includes determining a first plurality of calibration values for a first plurality of visits to a first revisit zone to which a mobile device repeatedly returns; determining a first relative calibration adjustment value based on the first plurality of calibration values; determining an adjusted absolute calibration value based on i) an absolute calibration value used to calibrate pressure measurements made by a pressure sensor of the mobile device, and ii) the first relative calibration adjustment value; and calibrating pressure measurements made by the pressure sensor of the mobile device using the adjusted absolute calibration value.

Abstract: Systems and methods are described for determining position of a receiver. The positioning system comprises a transmitter network including transmitters that broadcast positioning signals. The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals. The satellite signals are signals of a satellite-based positioning system. A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals. The positioning system comprises a server coupled to the remote receiver. A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals.

Abstract: A battery pack includes a battery, a first temperature sensor configured to provide a first temperature value associated with a temperature of the battery, a heat source disposed proximate to the battery and configured to heat the battery, a second temperature sensor configured to provide a second temperature value associated with a temperature of the heat source, and a control board coupled to the first temperature sensor and the second temperature sensor, wherein the control board is configured to receive the first temperature value and the second temperature value. The control board is configured to compare the first temperature value and the second temperature value to determine a temperature gradient between the battery and the heat source and transmit an alert if the temperature gradient exceeds a first temperature gradient threshold.

Abstract: Calibrating a pressure sensor of a mobile device incudes determining an absolute calibration value used to calibrate pressure measurements by a pressure sensor of a mobile device; determining a first revisit zone as a first location to which the mobile device repeatedly returns; determining first and second calibrations for first and second visits to the first revisit zone; determining a first relative calibration adjustment value based on a difference between the first and second calibrations; determining an adjusted absolute calibration value based on a sum of the absolute calibration value and the first relative calibration adjustment value; and estimating an altitude of the mobile device based on a pressure measurement by the pressure sensor and the adjusted absolute calibration value.