摘要:
Apparatus and method for positioning a wireless device. In one embodiment, a method for indoor positioning includes determining a reference location of a wireless device, based on satellite positioning, as the device passes between areas of satellite positioning signal reception and satellite positioning signal non-reception. While in the areas of non-reception, signals transmitted by wireless local area network (WLAN) access points (APs) and parameters of motion of the device are measured. Positions of the device are estimated while in the areas of non-reception based on the reference location and the parameters of motion. A positioning grid for positioning is generated based on the signals measured by the wireless device at the estimated positions.
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:
Embodiments of the invention provide a blending filter based on extended Kalman filter (EKF), which optimally integrates the IMU navigation data with all other satellite measurements tightly-coupled integration filter. This blending filter can be easily implemented with minor modification to the position engine of stand-alone GNSS receiver. Provided is a low-complexity tightly-coupled integration filter for sensor-assisted global navigation satellite system (GNSS) receiver. The inertial measurement unit (IMU) contains inertial sensors such as accelerometer, magnetometer, and/or gyroscopes Embodiments also include method for pedestrian dead reckoning (PDR) data conversion for ease of GNSS/PDR integration. The PDR position data is converted to user velocity measured at the time instances where GNSS position/velocity estimates are available.
摘要:
A system and method for operating a wireless transmitter and a global navigation satellite (“GNSS”) receiver coexistent in a mobile wireless device. A mobile wireless device includes a GNSS receiver and a wireless networking system. The wireless networking system includes a wireless transmitter. The wireless transmitter provides a first interference level signal to the GNSS receiver. The first interference level signal indicates a level of interference that the GNSS receiver can expect due to operation of the transmitter.
摘要:
Embodiments of the invention provide a method of adjusting a bandwidth of receivers. A plurality of outputs from a correlator engine are combined. User dynamics are sensed. Bandwidth of one or more receivers are adjusted. By detecting when the user is stationary, the Doppler frequency estimation can be corrected or the SNR can be boosted more both of which lead to improved performance. The embodiments allow a receiver to process signals in when the signal level would otherwise be too low—for example indoors. The embodiments can improve performance when one or more satellites are temporarily blocked but one or more satellites are still being tracked.
摘要:
A method and system for estimating noise variance. A method for noise variance estimation comprises receiving a first multi-sample symbol and receiving a second multi-sample symbol. The first multi-sample symbol is subtracted from the second multi-sample symbol to produce a set of noise samples. The set of noise samples is used to produce a noise variance estimate. The noise variance estimate is applied in various tasks (e.g. channel estimation, log-likelihood ratio computation, and/or minimum mean squared error equalization) to process data provided to a user.
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:
Systems and methods for dual-carrier modulation (DCM) encoding and decoding for communication systems. Some embodiments comprise a DCM encoder for applying a pre-transmission function to at least one 16-QAM input symbol and mapping resulting transformed symbols onto at least one larger constellation prior to transmission. Some embodiments joint decode, by a DCM decoder, a predetermined number of received data elements and compute a set of log-likelihood ratio (LLR) values for at least eight bits from a resulting at least one transformed symbol.
摘要:
Embodiments of the invention provide a system and method of hybrid automatic repeat-request (HARQ) processing. A viterbi decoder is coupled to and follows a descrambler. After the signal has been de-scrambled, it can be stored in a memory in case it needs to be recombined with another packet. This means that the log-likelihood ratios LLRs for each transmitted bit are stored in memory using a finite number of bits (for example, between 4 and 12 bits). If the packet that is currently being processed contains retransmitted information, then the de-scrambled output stored from a previous packet containing the same information can be loaded and combined with the current packet.
摘要:
A system and method for operating a wireless transmitter and a global navigation satellite (“GNSS”) receiver coexistent in a mobile wireless device. A mobile wireless device includes a GNSS receiver and a wireless networking system. The wireless networking system includes a wireless transmitter. The wireless transmitter provides a first interference level signal to the GNSS receiver. The first interference level signal indicates a level of interference that the GNSS receiver can expect due to operation of the transmitter.