Abstract:
A method for estimating the location of a beacon from an ensemble of measurements associated with said beacon, where, contained in each measurement, are GPS data from which surfaces of location may be extracted, together with the ID's of beacons detectable at the point of measurement, is disclosed. The method comprises extracting the canonical set of surfaces of location implicit in each of the associated measurements, and determining the estimate of the location of the beacon as the point for which a weighted sum of the squares of the distances to each of the surfaces so extracted is minimized. A system for the compilation of a database of beacon locations from measurements containing a time-stamped recording of the composite GPS signal (which recording is referred to as a datagram), together with the ID's and associated signal strengths of beacons detectable at the point of measurement, is also disclosed. The system comprises GPS signal processing means for extracting, from each time-stamped datagram, the canonic set of surfaces of location, and beacon location estimation means for estimating the location of a beacon from an ensemble of surfaces of location associated with said beacon.
Abstract:
A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes, where at least one of the operation modes is a peak current switching mode. Under the peak current switching mode, a switch controller controls the switch in the power converter to be kept on until the current through the switch reaches a peak current value corresponding to a given phase of the input voltage signal to the power converter. The peak current values have a reference shape, which may be a trapezoidal. The power converter may have any topology, such as a flyback-type power converter or a boost-type power converter.
Abstract:
A switching power converter for conversion of power between a source and a load includes a power switch, a free running oscillator for producing a drive signal to cycle the power switch ON and OFF, wherein the power switch, when coupled to the source and cycled ON and OFF, defines a pulse of power at the load, and a controller which regulates an output voltage at the load by varying the number of pulses of power occurring at the load over time.
Abstract:
The use of multiple GPS sensors provides the conceptual framework for novel techniques for reducing the minimum signal strength required by a GPS assistance system to acquire and accurately track GPS satellites at or near the horizon. A strong signal attenuation system for synthesizing GPS satellite-specific I/F signals, enabling more efficient and effective acquisition of GPS satellites, is disclosed, comprising N+1 reference GPS sensors, each with an omni-directional antenna and front end, for down converting composite GPS satellite signals, and strong signal suppression (SSS) means for synthesizing, from the I/F signals produced by the N+1 reference GPS sensors, a set of one or more I/F signals (corresponding to a set of designated satellites), each with at least N of the strongest potentially-interfering satellite signals suppressed.
Abstract:
A system for measuring the pseudo range from a target GPS sensor to a designated navigational satellite, for use in a satellite positioning system (SPS) is comprised of multiple GPS sensors for receiving and recording portions of the signals transmitted by designated navigational satellites, the recordings referred to as datagrams; and means for transmitting the datagrams to a datagram processing facility wherein the pseudo range from the target GPS sensor to the designated navigational satellite is derived. The datagram processing facility for deriving the pseudo range is further comprised of a pseudo range engine for deriving a pseudo range from a datagram originating with said target GPS sensor, the location of which is to be determined, the derivation accomplished with the aid of a perfect reference; a perfect reference engine for generating a perfect reference from one or more satellite-specific datagrams: and a strong signal suppression engine for synthesizing satellite-specific datagrams from I/F signals recorded by reference GPS sensors designated for the express purpose of perfect reference generation. The perfect reference reduces the minimum signal strength required to acquire and accurately track GPS satellites at or near the horizon.
Abstract:
A power converter for delivering power from a source to a load includes a switch, pulse generation circuitry producing one or more drive signals for cycling the switch ON and OFF, wherein if the switch is cycled ON and OFF according to a cycle of a drive signal, power is transferred from the source to the load, a comparator for comparing a feedback signal approximating an output voltage at the load to a reference, and a controller coupled to the pulse generation circuitry for controlling which, if any, cycle of a drive signal cycles the switch in response to an output of the comparator.
Abstract:
A method for estimating the location of a mobile Wi-Fi signal receiver from a database of independently obtained survey data, each survey datum consisting of a surface of location derived from a composite GPS signal, together with a Wi-Fi signature measured concurrently with the GPS signal measurement, is disclosed. The method comprises receiving a Wi-Fi signature, measured and recorded by said mobile. Wi-Fi signal receiver, at the location to be estimated; extracting from the database, an algorithmically-determined subset of surfaces of location, utilizing the Wi-Fi signature recorded by said mobile Wi-Fi signal receiver, and estimating the location of said mobile Wi-Fi signal receiver from said algorithmically-determined subset of surfaces of location. In one embodiment, the algorithmically-determined subset consists of those surfaces of location with Wi-Fi signatures identical to the mobile Wi-Fi signature; and the estimate of the location of said mobile Wi-Fi signal receiver is determined as the point for which the sum of the squares of the distances to each of the surfaces of location included in said algorithmically-determined subset is minimized.
Abstract:
A method for estimating the location of a beacon from an ensemble of measurements associated with said beacon, where, contained in each measurement, are GPS data from which surfaces of location may be extracted, together with the ID's of beacons detectable at the point of measurement, is disclosed. The method comprises extracting the canonical set of surfaces of location implicit in each of the associated measurements, and determining the estimate of the location of the beacon as the point for which the sum of the squares of the distances to each of the surfaces so extracted is minimized. A system for the compilation of a database of beacon locations from measurements containing a time-stamped recording of the composite GPS signal (which recording is referred to as a datagram), together with the ID's and associated signal strengths of beacons detectable at the point of measurement, is also disclosed. The system comprises GPS signal processing means for extracting, from each time-stamped datagram, the canonic set of surfaces of location, and beacon location estimation means for estimating the location of a beacon from an ensemble of surfaces of location associated with said beacon.
Abstract:
This disclosure relates to wireless battery charging of electronic devices such as wireless headsets/headphones. In one embodiment, an electronic device is provided comprising a speaker comprising a coil, and the coil is operative both to cause the speaker to produce sound and to receive energy transferred to the coil via inductive coupling. The received energy is used to recharge a rechargeable battery in the electronic device. In other embodiments, the coil used to receive the energy that recharges the battery is received by a coil other than the coil in the speaker.
Abstract:
An AC to DC power converter, comprising an input, an output, a plurality of pass elements connected in parallel between the input and output, and a controller for switching ON a subset of the plurality of pass elements. The controller sets an ON time for at least one pass element in the subset based on a load at the output and a phase angle of an input voltage at the input. The input voltage may comprise a single or multi-phase signal. The number of pass elements in the subset is based on the load. In one embodiment, each pass element comprising a pair of series-connected field effect transistors coupled source to source and operated in fully enhanced mode.