Abstract: A method to determine the polarity of navigation data from weak satellite signals is disclosed. After bit edge is detected, a method in frequency domain is used to determine the present bit polarity with the help of several prior data bits which are already known, is disclosed. The impact of residual frequency can be mitigated by frequency transform. This method is especially useful in removing the data modulation in the weak signal for subsequent long coherent integrations.

Abstract: A GPS Mobile Unit is described. The GPS Mobile Unit may include at least two antennas, at least two GPS receivers, and a position solution module in signal communication with the at least two GPS receivers.

Abstract: A Radio Frequency Receiver on a Single Integrated Circuit (“RFSIC”) is described. The RFSIC may include a mixer, a phase-locked loop (“PLL”) in signal communication with the mixer, and an on-chip auto-tuned RF filter in signal communication with both the mixer and PPL, such that the same PLL simultaneously tunes the frequency of the VCO and the frequency response of the auto-tuned RF filter.

Abstract: A positioning system receiver that mitigates cross correlation of received signals from positioning system satellite vehicles by generating the strong satellite vehicle signal and subtracting it from the received signal before correlation while eliminating the need for cross correlation signature without changing the C/A code.

Abstract: A positioning system receiver that mitigates narrowband interference by dynamically choosing the mitigation technique that yields the best interference mitigation capability with the least signal degradation to maximize receiver performance parameters such as receiver sensitivity, multipath resolution, and low power.

Abstract: A method and apparatus for real time clock brownout detection. A low power real time clock (RTC) operates continuously to keep time in a global positioning system (GPS) receiver while some receiver components are powered down. In various embodiments, a brownout detector circuit detects a loss of RTC clock cycles. If a loss of RTC clock cycles exceeds a predetermined threshold such that the RTC is not reliable for GPS navigation, an RTC status signal so indicates.

Abstract: A positioning system receiver that mitigates the effect of continuous wave (CW) carrier interference with post correlation processing in a satellite positioning receiver, while not distorting the signal waveform or degrading receiver sensitivity and performing in low signal and dynamic interference environments.

Abstract: A method and system for dynamic memory allocation and sharing in electronic systems. Embodiments include multi-channel signal processing, including continuously receiving multiple channels, wherein each channel comprises a discrete signal, and processing the multiple channels in a signal processing component on a time-multiplexed basis. Processing the multiple channels includes configuring the signal processing component for one of a plurality of operational modes, including allocating a memory into areas for storage of types of data, wherein certain areas are accessed by certain signal processing subsystems in certain manners. Configuring includes configuring the signal processing component to operate in different modes concurrently for different channels.

Abstract: An RF-to-IF converter includes radio frequency (RF) to intermediate frequency (IF) processing circuitry and a frequency synthesizer for generating a local oscillator signal and clocking signals. The frequency synthesizer includes a local oscillator (LO) output coupled to the processing circuitry, a baseband processor clock output, and clock generation circuitry for generating a baseband processor clock with a frequency of approximately 48 fo on the baseband processor clock output, where fo is 1.023 MHz.

Abstract: An interface between an RF processing section and a baseband processing section supports general purpose message transmission as well as satellite positioning system signal sample transmission between the RF processing section and the baseband processing section. The interface includes a bi-directional message serial interface and a data serial interface. The complexity of the data serial interface may be minimized by using a single data bit signal line in the data serial interface.

Abstract: A system is described that utilizes an imager in a wireless device in a wireless network and tags a digital image with positioning data.

Abstract: The present invention uses at least one amplitude bit to assist the phase-sampling technique used in digital receiver architectures. For digital receivers where the Intermediate Frequency (IF) is an integer multiple of the fundamental frequency f0, the present invention provides reduced processing complexity and reduced power consumption. The present invention allows the digital receiver to avoid performing coordinate rotation at high speeds, and replaces such a coordinate rotation with a simple phase subtraction. This replacement of the coordinate rotation allows the receiver to use a less complicated design, and to consume less power as a result.

Abstract: A system and a method for integrating the receipt and transmission of location information into VoIP phone systems. The system may include a location device that includes a SATPS receiver and an antenna together with one or more connectors that allow connection of the location device to other devices, such as a VoIP telephone and a router, that are connected to and made a part of a VoIP phone system. A method of operating such a system is also disclosed.

Abstract: Systems and methods for monitoring navigation state errors are provided. In this regard, a representative system, among others, includes a receiver that is configured to receive GPS signals and calculate pseudorange (PR) residuals, the receiver including a navigation state error manager that is configured to: calculate a distance traveled by the receiver having the PR residuals, determine whether a navigation state has errors based on the calculated PR residuals and calculated distance, and responsive to determining that the navigation state has errors, send an error message indicating that the navigation state has errors.

Abstract: Provided herein are methods and systems for efficient communication between a server and a client in an assisted navigation system. In one or more embodiments, the client, e.g., a GPS receiver, receives a set of parameters for a satellite from the server via a wireless or wired connection. The set of parameters includes a force parameter, initial condition parameters and time correction coefficients for the satellite. The receiver uses the received parameters in a numerical integration to compute the position of the satellite at a desired time. The set of parameters needed for the integration is small compared to current methods which require sending more data to the client. Thus these parameters require less communication resources to transmit. To further reduce the amount of data that needs to be transmitted, reference parameters may be subtracted from the original parameters before transmission from the server.

Abstract: Systems and methods are provided that compensate for frequency drift due to temperature variation without the need for a temperature sensor. In one embodiment, a navigation receiver with an integrated communication device receives a base station reference signal, which is used to periodically calibrate a local oscillator frequency. In another embodiment, the calibrated local oscillator frequency drives a counter that is used to provide code phase estimation at the start of satellite signal acquisition. To provide temperature compensation in one embodiment, the calibrated local frequency is used to drive one or more counters at different calibration rates (i.e., different time intervals between calibrations). Count values from these counters are used to determine compensation for frequency drift due to temperature variation based on predicted frequency drift variation patterns between calibrations.

Abstract: A data detection circuit within a global positioning system (GPS) satellite receiver operates to detect and decode data sent in a spread spectrum signal. The data detection circuit receives input from a radio receiver, the information containing data from a plurality of satellites. The data is supplied to a circular memory device, which determines which data corresponds to which satellite. The memory device sends the received signal to a matched filter, which decodes the signal received from each satellite. This signal is analyzed to determine whether a phase inversion due to data modulation on the received signal is present. The phase inversion can occur at boundaries, known as data epochs, in the received signal, and corresponds to data in the received signal. This data contains information relating to the position of each satellite and is collected by the data detection circuit for use by the GPS receiver.

Abstract: The present invention provides GPS receivers capable of tracking very weak GPS signals particularly in an indoor environment without assistance from an external server or a network. In a preferred embodiment, a GPS receiver initially acquires and locks onto GPS satellite signals to compute receiver position outdoors. The GPS receiver then tracks at least one satellite signal indoors to maintain acquisition parameters for quick acquisition of GPS signals. To save power, the receiver automatically goes to the sleep state and periodically wakes up, i.e., powers up, to maintain the at least one satellite signal tracking. During the wakeup state, the receiver collects ephemeris data from the at least one satellite signal when the ephemeris data needs to be updated for quick acquisition of GPS signals.

Abstract: The present invention provides methods and system for enabling a standalone navigation receiver capable of generating receiver specific predicted satellite orbits based on historical navigation data collected by and stored in the receiver. Thus, the navigation receiver is able to use the predicted satellite orbits to obtain better Time-To-First-Fix (TTFF) and position accuracy without the need of connecting to a remote server and the associated communications system. In an embodiment, a standalone navigation receiver having sufficient memory collects navigation data from navigation satellites and generates predicted satellite orbits using the collected navigation data. Under weak signal conditions when decoding of the navigation data is not possible, the receiver uses the predicted satellite orbits to predict the accurate satellite positions or the set of ephemeris and the associated pseudoranges. The predicted orbits may be accurate for several days without the reception of broadcast ephemeris.

Abstract: A system and method for providing temperature compensation in a oscillator component (such as a crystal oscillator component) that includes a closely-located temperature sensing device. The crystal oscillator component in example systems and methods is exposed to a temperature profile during a calibration procedure. Temperature and frequency data are collected and applied to coefficient generating function according to a temperature compensation model to generate a set of coefficients that are used in the temperature compensation model in an application device. The generated coefficients are stored in a coefficient memory accessible to an application device during operation.