摘要:
Apparatus and methods for scanning for access points (APs) for wireless local area network (WLAN) positioning. In one embodiment a wireless device includes a WLAN positioning system. The WLAN positioning system includes an AP scanner. The AP scanner is configured to determine which WLAN channels are being used by APs proximate to the wireless device. The AP scanner is also configured to scan for AP transmissions only the WLAN channels determined to be used by APs proximate to the wireless device. The AP scanner is further configured to extract signal strength and AP identification information for WLAN positioning from the AP transmissions on the scanned channels.
摘要:
A personal navigation device configured to determine heading readings continuously using data from a sensor in the personal navigation device. Heading readings are selected corresponding to a periodic event. A representative heading is determined from the selected heading readings. When a portion of the selected heading readings has a value within a range of the representative heading, a static heading indicator is asserted to indicate the personal navigation device is moving in a static heading. The static heading indicator may be used to smooth an estimated trajectory of the personal navigation device.
摘要:
A personal navigation device configured to determine heading readings continuously using data from a sensor in the personal navigation device. Heading readings are selected corresponding to a periodic event. A representative heading is determined from the selected heading readings. When a portion of the selected heading readings has a value within a range of the representative heading, a static heading indicator is asserted to indicate the personal navigation device is moving in a static heading. The static heading indicator may be used to smooth an estimated trajectory of the personal navigation device.
摘要:
Embodiments of the disclosure provide a cross coupled position engine architecture for sensor integration in a Global Navigation Satellite System. In one embodiment, a data processing engine for processing inertial sensor data within a positioning system receiver is disclosed. The data processing engine includes a first input for receiving the sensor data, and a second input for receiving a positioning data. The data processing system also includes a memory and a processor. The processor of the data processing system is coupled to the memory and to the first and second input. The processor of the data processing system is configured to calculate a net acceleration profile data from the inertial sensor data and from the positioning data. The net acceleration profile data calculated by the processor of the data processing system is used for the Global Positioning System (GPS) receiver to subsequently calculate a position and a velocity data.
摘要:
A method and system for reduced feedback transmit beamforming computes a matrix of channel transfer function coefficients. The matrix of channel transfer function coefficients is compressed by applying a rotation matrix having orthogonal columns to the matrix of channel transfer function coefficients to produce a compressed transfer function matrix having a reduced number of non-zero coefficients. The compressed matrix is fed back to a transmitting unit. Decompression of the transfer function coefficient matrix is not required. This compression does not cause any performance degradation for transmit beamforming. The transmitting unit computes a set of beamsteering coefficients from the compressed matrix and applies the coefficients to signals prior to transmission. The beamformed signals are transmitted to the receiving unit and post-coded to allow the receiving unit to see an effective diagonalized channel.
摘要:
A navigation system determines its usage mode. In some embodiments, a method comprises determining a usage mode of a navigation system based on at least one of an acceleration indicator, a speed indicator, and a magnet sensor. The usage mode is at least one of a pedestrian mode, a vehicular mode, an aerial mode, a train mode, and a marine mode. The method further comprises configuring a navigation subsystem based on the usage mode.
摘要:
Embodiments of the disclosure provide a cross coupled position engine architecture for sensor integration in a Global Navigation Satellite System. In one embodiment, a data processing engine for processing inertial sensor data within a positioning system receiver is disclosed. The data processing engine includes a first input for receiving the sensor data, and a second input for receiving a positioning data. The data processing system also includes a memory and a processor. The processor of the data processing system is coupled to the memory and to the first and second input. The processor of the data processing system is configured to calculate a net acceleration profile data from the inertial sensor data and from the positioning data. The net acceleration profile data calculated by the processor of the data processing system is used for the Global Positioning System (GPS) receiver to subsequently calculate a position and a velocity data.
摘要:
A method and system for reduced feedback transmit beamforming are provided. Some embodiments comprise computing a matrix of channel transfer function coefficients. The matrix of channel transfer function coefficients is compressed by applying a rotation matrix having orthogonal columns to the matrix of channel transfer function coefficients to produce a compressed transfer function matrix having a reduced number of non-zero coefficients. The compressed matrix is fed back to a transmitting unit. Decompression of the transfer function coefficient matrix is not required. This compression does not cause any performance degradation for transmit beamforming. The transmitting unit computes a set of beamsteering coefficients from the compressed matrix and applies the coefficients to signals prior to transmission. The beamformed signals are transmitted to the receiving unit and post-coded to allow the receiving unit to see an effective diagonalized channel.
摘要:
Embodiments provide a system and method for efficiently classifying different channel types in an orthogonal frequency division multiplexing (OFDM) system. Embodiments quantify the frequency selectivity in a channel by measuring the variation in a particular channel statistic across sub-carriers in an OFDM system, involve minimal complexity in implementation, and can be used in a variety of scenarios. One embodiment is a method for classifying channels in an OFDM system, comprising measuring variation of at least one channel statistic across sub-carriers, quantifying the variation to determine a measurement value, and applying the measurement value to at least one threshold to classify the channel.
摘要:
A system comprises a gyroscope configured to produce a gyroscope signal, an accelerometer configured to produce an accelerometer signal, and a filter unit coupled to the gyroscope and having a configurable bandwidth. The filter unit configured to filter the gyroscope signal. The system also comprises control logic that is configured to alter the bandwidth of the filter unit based on the accelerometer signal.