US20070008218A1 - Tracker architecture for GPS systems - Google Patents

Tracker architecture for GPS systems Download PDF

Info

Publication number
US20070008218A1
US20070008218A1 US11475383 US47538306A US2007008218A1 US 20070008218 A1 US20070008218 A1 US 20070008218A1 US 11475383 US11475383 US 11475383 US 47538306 A US47538306 A US 47538306A US 2007008218 A1 US2007008218 A1 US 2007008218A1
Authority
US
Grant status
Application
Patent type
Prior art keywords
gps
architecture
bus structure
engine
tracking
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US11475383
Inventor
Nicolas Vantalon
Leon Peng
Gregory Turetzky
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
CSR Technology Inc
Original Assignee
CSR Technology Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/24Acquisition or tracking or demodulation of signals transmitted by the system
    • G01S19/30Acquisition or tracking or demodulation of signals transmitted by the system code related
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/21Interference related issues; Issues related to cross-correlation, spoofing or other methods of denial of service
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/35Constructional details or hardware or software details of the signal processing chain
    • G01S19/37Hardware or software details of the signal processing chain
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S5/00Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
    • G01S5/0009Transmission of position information to remote stations
    • G01S5/0018Transmission from mobile station to base station
    • G01S5/0027Transmission from mobile station to base station of actual mobile position, i.e. position determined on mobile
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S5/00Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
    • G01S5/0009Transmission of position information to remote stations
    • G01S5/0018Transmission from mobile station to base station
    • G01S5/0036Transmission from mobile station to base station of measured values, i.e. measurement on mobile and position calculation on base station
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/03Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
    • G01S19/09Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing processing capability normally carried out by the receiver
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/24Acquisition or tracking or demodulation of signals transmitted by the system
    • G01S19/25Acquisition or tracking or demodulation of signals transmitted by the system involving aiding data received from a cooperating element, e.g. assisted GPS
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/24Acquisition or tracking or demodulation of signals transmitted by the system
    • G01S19/26Acquisition or tracking or demodulation of signals transmitted by the system involving a sensor measurement for aiding acquisition or tracking

Abstract

A tracker architecture for Global Positioning System (GPS) receivers is disclosed. A typical tracker comprises an RF front end and GPS architecture. The architecture comprises a bus structure, a Central Processing Unit (CPU) core, cache, RAM, and ROM memories, and a GPS engine that comprises a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals. The GPS architecture can couple to at least two different protocol interfaces via the bus structure, where the protocol interfaces are commonly used in different applications.

Description

    CROSS REFERENCE TO RELATED APPLICATIONS
  • This application claims priority under 35 U.S.C. 119(e) of U.S. Provisional Patent Application No. 60/306,620, filed Jul. 18, 2001, entitled “TRACKER ARCHITECTURE FOR GPS SYSTEMS,” by Nicolas Vantalon et al., which application is incorporated by reference herein.
  • This application is also related to U.S. Pat. No. 5,901,171, by Sanjai Kohli et al., entitled “TRIPLE MUTIPLEXING SPREAD SPECTRUM RECEIVER,” and related to U.S. Pat. No. 6,278,403, by Leon Kuo-Liang Peng et al, entitled “AUTONOMOUS HARDWIRED TRACKING LOOP COPROCESSOR FOR GPS AND WAAS RECEIVER,” both of which applications are hereby incorporated by reference herein.
  • BACKGROUND OF THE INVENTION
  • 1. Field of the Invention
  • The present invention relates in general to Global Satellite System (GSS) receivers, and in particular to a tracker architecture for Global Positioning System (GPS) systems.
  • 2. Description of the Related Art
  • Currently, there are many GPS systems available that can acquire, track, and navigate using GPS signals. However, the navigation and tracking architectures for these systems vary widely. Many of these systems are not optimized for tracking or navigation, and are designed to work with only one type of GPS system.
  • SUMMARY OF THE PRESENT INVENTION
  • To minimize the limitations in the prior art described above, and to minimize other limitations that will become apparent upon reading and understanding the present specification, the present invention discloses, a tracker architecture for Global Positioning System (GPS) receivers. An architecture in accordance with the present invention comprises a bus structure, a Central Processing Unit (CPU) core, cache, RAM, and ROM memories, and a GPS engine that comprises a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals. The GPS architecture can couple to at least two different protocol interfaces via the bus structure, where the protocol interfaces are commonly used in different applications.
  • The present invention is a member of digital signal processors used for a GPS navigation architecture. The present invention is built on a state-of-the-art, low power, 0.18 micron CMOS process. This highly integrated design includes a compatible GPS/WAAS (wide area augmentation signal) Digital Signal Processor (DSP) engine, Satellite Signal Tracking Engine (SSTE), BEACON DSP, ARM microprocessor, real time counter (RTC), dual UART, interrupt controller, ROM, SRAM, on-chip ADC, Multiple serial interfaces (including I2C, USB, CAN, J1850 and SPI), two-way associate cache, and bus interface unit (BIU).
  • The present invention provides the architecture flexibility to support all GPS market segments: Cellular Phone, Car Navigation, GPS Hand-helds, Consumer Electronics, PC accessory and others, because the present invention integrates the CPU core, memory, GPS engine and other system peripherals. As a minimum system configuration, a receiver can comprise an RF front-end, and the present invention, which is used as a backend digital component. The present invention also has extra computing power to run applications other than GPS tracking and navigation. The present invention is fully compatible with many types of tracking and navigation software.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • Referring now to the drawings in which like reference numbers represent corresponding parts throughout:
  • FIG. 1 illustrates an architecture in accordance with the present invention.
  • DETAILED DESCRIPTION OF THE DRAWINGS
  • In the following description of the preferred embodiment, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration a specific embodiment in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.
  • Overview
  • When integrating GPS components and receivers with other electronics, e.g., cellular telephones, automotive systems, etc., the GPS components must be readily compatible with such systems and still retain the ability to acquire and track the GPS satellites under the conditions presented by each of the environments that the GPS components will be introduced into. The present invention combines the systems typically present in a GPS baseband tracker architecture, and provides a single, multi-function interface that is compatible with several different protocols, such that a baseband processor made using the tracker architecture of the present invention can be used in several different applications.
  • A baseband processor used in the tracker architecture of the present invention typically is manufactured using a 0.18 micron low power CMOS process. This allows for smaller die sizes, as well as low power consumption.
  • The present invention allows for different operating voltages, typically 3.3 volts, 2.5 volts, or 1.8 volts dc. These voltages are used not only for the baseband processor, but also for the Real Time Clock (RTC) and for the I/O drivers used with the architecture of the present invention. To conserve power, the internal core typically operates at 1.8 volts, so that the processor and other integrated portions of the present invention use as little power as possible. Further, the present invention operates over a wide range of temperatures, typically −40 to +85 degrees Centigrade, and also meets the QS9000 standard for semiconductor circuit manufacture.
  • Block Diagram
  • FIG. 1 illustrates a block diagram of the present invention. Appendix A illustrates some sample terms used throughout this disclosure and in FIG. 1. Appendix B illustrates the input/output description of the present invention.
  • Architecture 100 of the present invention is shown with several components described below.
  • ARM7TDMI
  • The ARM7TDMI 102 is a member of the Advanced RISC Machines (ARM) family of general purpose 32-bit microprocessors, which offer high performance for very low power consumption. Although described herein as an ARM7 or an ARM7TDMI 102, it can be appreciated by one knowledgeable in the art that other microprocessors can be used in lieu of or in conjunction with the ARM7TDMI 102 without departing from the scope of the present invention. The ARM7TDMI 102 is intended to run at the maximum speed of 50 MHz to deliver an approximate maximum 40 Million Instructions per second (Mips).
  • Cache
  • A 9K byte RAM cache 104 is typically used for the cache module. It can function as a local RAM for timing critical code loops, or as a cache memory. When the cache is disabled, the 9 k byte of memory can be used as an on chip memory if desired. In cache mode, a total of 8K bytes are used as code/data cache 106 and 1 K byte is used as tag memory 108. A two-way set associated cache can be activated, as shown with data cache 110 and tag cache 112, The Cache 104 can be used for both instruction code and data. A LRU and write through logic can also be activated if desired.
  • Processor Memory
  • The architecture 100 also incorporates an on-chip low power 4K×32 SRAM 114 for data and 16K×32 Boot ROM 116 for code. The ROM 116 is typically programmed in the prototype stages for supporting the tracker only code and the other program code is typically contained in external memory (not shown). The ROM 116 code can have several versions, and may be changed depending on which version of the architecture or which revision of the chip is used. The BIU 118 can access the external memory as needed, and supports byte, Hword, and word accesses to the external memories. The architecture 100 is able to boot from internal or external memory regarding a power up configuration.
  • Internal ROM
  • The architecture 100 of the present invention includes internal ROM 116 code that provides at least two primary functions and one or more secondary functions. The primary functions include a boot loader program to load user code into the internal memory 114 and/or cache 104 of the architecture 100 and a receiver interface program to control the SSTE and WAAS channel demodulator. This receiver interface program will report data and provide control to the user via one of the built in serial interfaces. The receiver interface program also optionally includes an autonomous mode, which enables the architecture 100, along with autonomous code stored in the ROM 116, when coupled to a RF front end, to acquire, and track the GPS signal without any external intervention by the user. The user can selectively choose the use of the autonomous mode, and the autonomous code stored in the ROM 116, either automatically or manually. The secondary functions include built-in-test functions, and functions to allow insertion of new code into the internal RAM 114 and/or cache 104. The inserted code can incorporate itself into and expand the functions of the receiver interface function. Additional optional secondary functions include a program to perform automatic detection of externally interfaced memory chips to allow expansion or replacement of the computer instructions resident in the ROM 116.
  • ADC
  • The Analog-to-Digital Converter (ADC) module 117 is typically a 14 bit module that comprises a sinc3 filter and the filter's interface to the CPU 102. The Sinc3 filter processes the single bit over-sampled output from the sigma-delta modulator, and outputs the 16-bit wide data, at a 50 Hz sample rate, to four separate registers corresponding to the input channels.
  • Peripheral Bridge
  • An internal peripheral bridge 120 is used as the bridge between the ARM7TDMI 102, CPU bus 122, and the IP bus (Also called the SiRF IP Bus, or SIPB). The SIPB provides an adaptive connection to various types of peripherals for ease of future system expansion. The SIPB protocol is synchronous to the CPU clock. The fundamentals of the protocol take a minimum of three clock cycles to access all the peripherals. The bridge 120 also adds the wait state insertion capability for the DSP engine and other peripherals, which may take more clock cycles to access. Two bridges 120 are designed into the present invention, and both bridges can be either 32-bit or 16-bit. One bridge 120 is AMBA1D compatible and the other is AMBA1E compatible.
  • GPS/WAAS Engine
  • The present invention incorporates a GPS/WAAS engine 124 that tracks, receives, and demodulates both GPS and WAAS satellite signals. To accelerate the initial acquisition, the engine 124 uses a multiple frequency bin correlator, which performs a correlation on the 4 coherently integrated samples for each of 240 taps, and generates 8 frequency bins as an output. Multiple frequency bin correlator outputs are non-coherently integrated and the final result will be peak detected to locate the two largest values. The coherent and non-coherent integration counters are independently programmable in the resolution of segment. The coherent integration and non-coherent integration start point can be set at a user time ms boundary and at a half ms boundary for WASS data. The multi-path mitigation and early-late hardware runs in parallel with the tracking channels. When using the multi-path mitigation and neatly-late modes, the tape of the multi-path correlator provides an improved restoring force for the code tracking. To support the WAAS channel demodulation, the convolution decoder is added for WAAS channel demodulated data. All the satellite channels are configurable for either CPU or SSTE. The shared memory micro-architecture also provides a low power solution, as well as providing a low gate count.
  • SSTE
  • In initial acquisition mode, the tracker (also called the SSTE) 125 autonomously steps through the code, frequency search windows, and histogram to perform strong side lobe rejection and sync verification.
  • In track mode, the SSTE 125 executes pull-in, narrow track, and bit sync, data demodulation. Functional blocks include code/Costas lock detect, Costas/AFC loop filter, code loop filter, bit sync histogram, sample normalization, SNR measurement, bit demodulation. When code lock is lost, reacquisition executes resume normal, stay modes, 10 Hz track status and demodulated data output to software include code, carrier, bitsync status, demodulated data bits, accumulated |I|, |Q|, code, carrier phase. The SSTE 125 handles all mode transitions autonomously with software override capability.
  • Beacon Processor
  • The beacon processor 126 uses the frequency discriminator approach chosen over coherent QPSK demodulation or FSK non-coherent demodulation as the best trade off between performance and implementation complexity. The signal interface is via a 10 bit external A/D on the synchronous serial interface. The hardware performs downconversion, decimation, filtering, discriminator calculation, bit sync, and data demodulation. The software programs the data rate and downconversion frequency. The hardware outputs the data at a HW/SW interface at 50 Hz rate. The ADC peak clipping scheme is used to combat strong pulse jamming. A 3-pole cascaded Butterworth low pass filter is used before the frequency discriminator.
  • Power Management
  • The power management block 128 provides the controlling software, and optimizes the power for all the major blocks in the design of the present invention. The wake-up interrupt logic in the interrupt controller facilitates the wake-up on any interrupt as selected by the controlling software. The minimum power configuration of the chip is used to apply the power to the RTC module 130, and battery back-up RAM is typically then active. The rest of circuit is in a power down mode. The target power consumption of the power down is around 5 uA. During the standby, the chip typically uses less than 100 uA.
  • RF Interface
  • As part of the standard interface for the architecture 100, connections to the RF portion of the GPS receiver are required. Signal wires of PWM 132 AGC protocol are implemented for a 1 kHz automatic gain control (AGC) interface. A single ended PECL physical interface is used for two GPS clock lines and two GPS/WAAS data lines. UART
  • Both the transmit and receive sides of each UART port 134 contain a 16-byte deep FIFO with a selectable bit rate from 1200 to 115.2 Kbps. The parity, data bits and stop bits are also configurable. Each receive resister also provides error signals for frame error, parity error, overrun error, and break interrupt.
  • Timer
  • The present invention incorporates a timer function 136 whereby a free-running counter may be used to raise interrupts when the count value reaches programmable thresholds. The clock for this timer function 136 block may be sourced from either the 49.107 MHz clock, the 38.192 MHz clock, an external user-defined clock as shown in FIG. 1, or from the 32 KHz input (default), with the source selection programmable by software. Furthermore, 1, 8, 32, 128 or 2048 may divide the selected source clock for this block.
  • Watch-Dog
  • The present invention provides a watchdog function 138 whereby a free-running counter requires a regular service by the controlling software; otherwise a watchdog reset is issued which in turn causes a full system reset to the device excluding the RTC 130.
  • RTC
  • The RTC 130 is used to maintain seconds, minutes, hours and days for the architecture 100 while requiring extremely low power. It has a separated power input so that the rest of core logic can be shut down but time maintained at the RTC 130 for the next power on. This RTC 130 enables a low power state, and other power management features, to significantly reduce power consumption during normal operation. The RTC 130 of the present invention contains a 1024×16 memory backup RAM for the critical information. The RTC 130 of the present invention is typically clocked by a 32.784 KHz signal with an on-chip oscillator.
  • Interrupt Controller
  • The interrupt controller manages all possible sources of interrupts from within the Peripheral Bus. These include the GPS/WAAS engine, SSTE, Beacon, DSP, UART, CAN, USB, SPI, J1850 and up to three external user interrupts.
  • Bus Interface Unit
  • The Bus Interface Unit (BIU) 118 provides simple and direct memory-mapped access to the external peripherals. The present invention memory interface block allows direct connection to a variety of 8-bit, 16-bit RAMs or ROMs on the system interface. The chip of the present invention generates the needed control signals for external RAMs and ROMs. The programmable wait state control registers set by the software to support wide range of speed of the external memory. It also supports the wait state insertion protocol to add the additional wait states. The BIU 118 also can support the parallel interface protocol to allow the external host CPU to access the internal memorys 114, 104, and 116, and other registers of the present invention.
  • Timer/PWM
  • The present invention also provides a Pulse Width Modulated (PWM output signal via the PWM block 132. The frequency and duty cycle is programmable. In addition, the present invention optionally provides a timer function whereby a free-running counter may be used to raise interrupts when the count value reaches a programmable threshold. Similarly, the present invention provides a watchdog function whereby a free-running counter requires a regular service by the controlling software.
  • Programmable Interface of the Present Invention
  • The architecture of the present invention comprises a multiple-protocol interface that can be connected to several different types of standard interfaces. For example, I2C, SPI, CAN, USB, J1850, MOST, Parallel, and Address/Data Bus interfaces can connect to the architecture 100 via a single input as described below. The architecture can either be programmed a priori to accept a given input, e.g., USB inputs, or can automatically detect a specific type of signal or the presence of a signal on a given signal line, and self-program to accept and transmit data using that protocol. Several types of interfaces compatible with the architecture 100 of the present invention are as follows:
  • I2C
  • The present invention I2C interface 140 is capable of both master and slave modes of operation in the multi-master environment as defined in the I2C standard protocol that is incorporated by reference herein. There are two pin bi-directional signals in the I2C interface 140.
  • SPI
  • The SPI block 142 is a standard 4-pin serial peripheral interface for inter-IC control communication. It contains a 10 word×24-bit receive buffer for message buffering in order to reduce the frequency of interrupt of the ARM processor 102.
  • CAN
  • The CAN 2.0 144 interface is compatible with both class A (11-bit identifier) and class B (29-bit identifier) interfaces. The data/message rate for FMEA (position fix data) is about 4 Kbit/sec including 5-6 FMEA messages of approximately 60 Bytes each. The rate for Dead Reckoning (DR) would need about 50-100 Kbit/sec. The CAN 144 supports both 10 Kbit/sec and 1 Mbit/sec message rates. The physical transceiver interface is typically outside of the chip.
  • USB
  • The device of the present interface contains a high speed USB interface 146 including an on-chip physical transceiver. The USB interface 146 is compliant with revision 1.1 of the USB standard, giving an interface transfer rate of 12 Mbits−1. The USB interface 146 supports a control channel endpoint and 2 interrupt-type endpoints, each with a minimum of 16 bytes of local storage. It also supports 2 bulk transfer points with 64 bytes each of local storage.
  • J1850.
  • The present invention also comprises data link and protocol layers that support the J1850 Class II VPW protocol interface 148 for Chrysler, Toyota, and GM J1850 networks. The physical link is a single wire and single ended at 7V. The speed is 10.4 Kbps with CRC & message filtering in software and hardware.
  • GPIO
  • The device of the present invention provides a number of general purpose Input/Outputs (GPIO) at interface 150, accessible by the embedded processor. The status of the general purpose inputs way be determined by polling.
  • These general purpose I/Os 150 are multiplexed with other functions where possible to increase the number of GPIO pins without increasing the pin budget. The exact number available depends upon which version of the die is being bonded out.
  • MOST, and Other Supported Interfaces
  • The interface of the present invention also comprises a MOST interface 152, a parallel port interface 154, and an address/data bus interface 156. The MOST interface 152 is capable of carrying MPEG level data on an automotive optical bus, and is used to control various peripherals in an automotive environment. Parallel port interface 154 is typically used to connect the tracker architecture 100 to a computer other than the ARM 102.
  • IO Specification
  • A typical Input/Output specification for the present invention is shown in Appendix B.
  • Last Segment
  • Access to the memory RAM1 158, RAM2 160, RAM3 162, and RAM4 164, when the engine locked the memory, typically generated an abort instruction to the CPU. This ERROR generation has been removed for the present invention and replace by a WAIT function. Every time the CPU will access the engine RAM1 158 through RAM4 164 when the engine locked them the SBU bridge will keep BWAIT High until the engine release the memory, and execute the access to the memory.
  • Synchronous Memories
  • All internal memories 104, 114, 116, and 158-164 are synchronous. All DSP memories are connected to ENGCLK_N.
  • Operation of the Interface
  • The interface 166, which comprises all of the protocols mentioned herein, allows the tracker architecture 100 of the present invention to connect to various input and output signals that are present in the environments that the architecture 100 will typically reside in. The interface 166 can be pre-programmed by the chip manufacturer, prior to shipment to a specific customer, to accept a given protocol, in essence, enabling one or more of the protocols, or disabling one or more of the protocols, as desired. Further, the architecture 100 can be auto-detecting in nature, where the architecture senses the presence or absence of certain signals, and through the detection or absence of certain signals, determines which protocol the architecture 100 is connected to. The architecture then responds in the given protocol.
  • As an example, and not meant to be a limitation of the present invention, the architecture can be a priori programmed to accept only the J1850 interface 148 inputs and the GPIO 150 inputs, and reject inputs from an I2C interface 140. In an alternative of this example, again not by way of limitation, once the architecture 100 is connected to J1850 interface 148 input signals, the architecture 100 can automatically detect which of the protocols is present and accept the J1850 148 signals, and respond in kind.
  • Manual programming after delivery is also possible, as is changing of the protocol that interface 166 and architecture 100 will accept.
  • Conclusion
  • This concludes the description of the preferred embodiment of the invention. The following paragraphs describe some alternative methods of accomplishing the same objects. The present invention, although described with respect to GPS systems, can be utilized with any Satellite Positioning System (SATPS) without departing from the scope of the present invention. Further, other CPU processors can be used without departing from the scope of the present invention.
  • In summary, a tracker architecture for Global Positioning System (GPS) receivers in accordance with the present invention comprises a bus structure, a Central Processing Unit (CPU) core, cache, RAM, and ROM memories, and a GPS engine that comprises a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals. The GPS architecture can couple to at least two different protocol interfaces via the bus structure, where the protocol interfaces are commonly used in different applications.
  • The foregoing description of the preferred embodiment of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention not be limited by this detailed description, but by the claims appended hereto.

Claims (21)

  1. 1. A Global Positioning System (GPS) architecture used for tracking at least one GPS satellite, comprising:
    a bus structure,
    a Central Processing Unit (CPU) core comprising a microprocessor, coupled to the bus structure;
    a cache memory coupled to the bus structure for storing software code;
    a random access memory, coupled to the bus structure, for storing data;
    a read only memory, coupled to the bus structure, for storing a boot program; and
    a GPS engine, comprising:
    a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals,
    wherein the GPS architecture can couple to at least two different protocol interfaces via the bus structure.
  2. 2. The GPS architecture of claim 1, wherein the cache memory can be used as a local random access memory.
  3. 3. The GPS architecture of claim 2, wherein the CPU can be used for running applications other than GPS tracking.
  4. 4. The GPS architecture of claim 3, wherein the GPS engine further comprises a beacon processor.
  5. 5. The GPS architecture of claim 3, wherein the GPS engine runs on a separate bus structure.
  6. 6. The GPS architecture of claim 5, wherein the GPS engine further comprises inputs from a real time clock external to the GPS engine.
  7. 7. The GPS architecture of claim 6, further comprising a bus interface units.
  8. 8. The GPS architecture of claim 7, wherein the protocol interfaces are selected from a group comprising I2C, CAN, PWM, SPI, J1850, USB, GPIO, MOST, parallel, and an address/data bus interface.
  9. 9. The GPS architecture of claim 8, wherein the protocol interface is selected a priori.
  10. 10. The GPS architecture of claim 8, wherein the protocol interface is selected by the GPS architecture through sensing a signal in the protocol interface.
  11. 11. A Global Positioning System (GPS) architecture used for tracking at least one GPS satellite, comprising:
    a bus structure,
    a Central Processing Unit (CPU) core comprising a microprocessor, coupled to the bus structure;
    a cache memory coupled to the bus structure for storing software code;
    a random access memory, coupled to the bus structure, for storing data and for storing autonomous code used for tracking at least one GPS satellite;
    a read only memory, coupled to the bus structure, for storing a boot program; and
    a GPS engine, comprising:
    a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals,
    wherein the GPS engine can selectively use the stored autonomous code for tracking at least one GPS satellite.
  12. 12. The GPS architecture of claim 11, wherein the architecture can couple, via the bus structure, to at least two different protocol interfaces, selected from a group comprising I2C, CAN, PWM, SPI, J1850, USB, GPIO, MOST, parallel, and an address/data bus interface.
  13. 13. The GPS architecture of claim 12, wherein the cache memory can be used as a local random access memory.
  14. 14. The GPS architecture of claim 13, wherein the CPU can be used for running applications other than GPS tracking.
  15. 15. The GPS architecture of claim 14, wherein the GPS engine further comprises a beacon processor.
  16. 16. The GPS architecture of claim 14, wherein the GPS engine runs on a separate bus structure.
  17. 17. The GPS architecture of claim 16, wherein the GPS engine further comprises inputs from a real time clock external to the GPS engine.
  18. 18. The GPS architecture of claim 17, further comprising a bus interface unit.
  19. 19. The GPS architecture of claim 17, wherein the protocol interface is selected a priori.
  20. 20. The GPS architecture of claim 17, wherein the protocol interface is selected by the GPS architecture through sensing a signal in the protocol interface.
  21. 21. A Global Positioning System (GPS) architecture used for tracking at least one GPS satellite, comprising:
    a bus structure,
    a Central Processing Unit (CPU) core comprising a microprocessor, coupled to the bus structure,
    a cache memory coupled to the bus structure for storing software code;
    a random access memory, coupled to the bus structure, for storing data;
    a read only memory, coupled to the bus structure, for storing a boot program; and
    a GPS engine, comprising:
    a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals,
    wherein the GPS architecture can couple, via the bus structure, to at least two different protocol interfaces, and wherein the protocol interface is selected by the GPS architecture automatically.
US11475383 2000-08-24 2006-06-26 Tracker architecture for GPS systems Abandoned US20070008218A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US10775870 US7026986B2 (en) 2000-08-24 2004-02-10 Location services system that reduces auto-correlation or cross-correlation in weak signals
US11475383 US20070008218A1 (en) 2004-02-10 2006-06-26 Tracker architecture for GPS systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US11475383 US20070008218A1 (en) 2004-02-10 2006-06-26 Tracker architecture for GPS systems

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US10775870 Continuation US7026986B2 (en) 2000-08-24 2004-02-10 Location services system that reduces auto-correlation or cross-correlation in weak signals

Publications (1)

Publication Number Publication Date
US20070008218A1 true true US20070008218A1 (en) 2007-01-11

Family

ID=37034665

Family Applications (2)

Application Number Title Priority Date Filing Date
US11345635 Active US7365680B2 (en) 2000-08-24 2006-01-31 Location services system that reduces auto-correlation or cross-correlation in weak signals
US11475383 Abandoned US20070008218A1 (en) 2000-08-24 2006-06-26 Tracker architecture for GPS systems

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US11345635 Active US7365680B2 (en) 2000-08-24 2006-01-31 Location services system that reduces auto-correlation or cross-correlation in weak signals

Country Status (1)

Country Link
US (2) US7365680B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090073037A1 (en) * 2005-06-08 2009-03-19 Nxp B.V. Gps processing arrangement
US10020968B1 (en) * 2015-03-18 2018-07-10 National Technology & Engineering Solutions Of Sandia, Llc Coherent radar receiver that comprises a sigma delta modulator

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE60144522D1 (en) * 2000-08-24 2011-06-09 Sirf Tech Inc Device for reducing auto-correlation and cross-correlation with weak CDMA signals
US7852908B1 (en) 2007-06-08 2010-12-14 Rf Micro Devices, Inc. Combined digital filter and correlator
US20090153397A1 (en) * 2007-12-14 2009-06-18 Mediatek Inc. Gnss satellite signal interference handling method and correlator implementing the same

Citations (93)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4445118A (en) * 1981-05-22 1984-04-24 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Navigation system and method
US4462712A (en) * 1981-07-16 1984-07-31 Quality Mat Company Method and apparatus for a construction site flooring system
US4463357A (en) * 1981-11-17 1984-07-31 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Method and apparatus for calibrating the ionosphere and application to surveillance of geophysical events
US4578678A (en) * 1983-11-14 1986-03-25 The United States Of America As Represented By The United States National Aeronautics And Space Administration High dynamic global positioning system receiver
US4667203A (en) * 1982-03-01 1987-05-19 Aero Service Div, Western Geophysical Method and system for determining position using signals from satellites
US4754465A (en) * 1984-05-07 1988-06-28 Trimble Navigation, Inc. Global positioning system course acquisition code receiver
US4809005A (en) * 1982-03-01 1989-02-28 Western Atlas International, Inc. Multi-antenna gas receiver for seismic survey vessels
US4821294A (en) * 1987-07-08 1989-04-11 California Institute Of Technology Digital signal processor and processing method for GPS receivers
US4847862A (en) * 1988-04-07 1989-07-11 Trimble Navigation, Ltd. Global positioning system course acquisition code receiver
US4894662A (en) * 1982-03-01 1990-01-16 Western Atlas International, Inc. Method and system for determining position on a moving platform, such as a ship, using signals from GPS satellites
US4928106A (en) * 1988-07-14 1990-05-22 Ashtech Telesis, Inc. Global positioning system receiver with improved radio frequency and digital processing
US4998111A (en) * 1989-11-27 1991-03-05 Motorola, Inc. CPS transform correlation receiver and method
US5014066A (en) * 1982-03-01 1991-05-07 Western Atlas International, Inc. System for simultaneously deriving position information from a plurality of satellite transmissions
US5036329A (en) * 1989-11-22 1991-07-30 Pioneer Electronic Corporation GPS satellite signal tracking method for GPS receivers
US5089822A (en) * 1990-02-13 1992-02-18 Avion Systems, Inc. Interrogation signal processor for air traffic control communications
US5101416A (en) * 1990-11-28 1992-03-31 Novatel Comunications Ltd. Multi-channel digital receiver for global positioning system
US5108334A (en) * 1989-06-01 1992-04-28 Trimble Navigation, Ltd. Dual down conversion GPS receiver with single local oscillator
US5111150A (en) * 1990-09-26 1992-05-05 Garmin Corporation Precision phase shift system
US5134407A (en) * 1991-04-10 1992-07-28 Ashtech Telesis, Inc. Global positioning system receiver digital processing technique
US5187450A (en) * 1992-03-13 1993-02-16 Trimble Navigation Limited Voltage controlled oscillator suitable for complete implementation within a semiconductor integrated circuit
US5202829A (en) * 1991-06-10 1993-04-13 Trimble Navigation Limited Exploration system and method for high-accuracy and high-confidence level relative position and velocity determinations
US5202694A (en) * 1991-09-10 1993-04-13 Trimble Navigation P-code generation
US5219067A (en) * 1992-02-04 1993-06-15 Trimble Navigation Limited Keyboard pad structure for electronic devices
US5223844A (en) * 1992-04-17 1993-06-29 Auto-Trac, Inc. Vehicle tracking and security system
US5225842A (en) * 1991-05-09 1993-07-06 Navsys Corporation Vehicle tracking system employing global positioning system (gps) satellites
US5282228A (en) * 1991-12-09 1994-01-25 Novatel Communications Ltd. Timing and automatic frequency control of digital receiver using the cyclic properties of a non-linear operation
US5296861A (en) * 1992-11-13 1994-03-22 Trimble Navigation Limited Method and apparatus for maximum likelihood estimation direct integer search in differential carrier phase attitude determination systems
US5306971A (en) * 1992-07-23 1994-04-26 Proxim, Inc. Binary controlled digital tapped delay line
US5311197A (en) * 1993-02-01 1994-05-10 Trimble Navigation Limited Event-activated reporting of vehicle location
US5311149A (en) * 1993-03-12 1994-05-10 Trimble Navigation Limited Integrated phase locked loop local oscillator
US5311195A (en) * 1991-08-30 1994-05-10 Etak, Inc. Combined relative and absolute positioning method and apparatus
US5313457A (en) * 1992-04-14 1994-05-17 Trimble Navigation Limited Code position modulation system and method for multiple user satellite communications
US5313069A (en) * 1991-12-31 1994-05-17 Trimble Navigation Distance measuring system of an extendable strip having light reflecting and non-reflecting polygons
US5319374A (en) * 1993-02-02 1994-06-07 Trimble Navigation Limited Precise universal time for vehicles
US5321799A (en) * 1992-04-17 1994-06-14 Proxim, Inc. Signalling transition control in a modulated-signal communications system
US5323322A (en) * 1992-03-05 1994-06-21 Trimble Navigation Limited Networked differential GPS system
US5323164A (en) * 1992-03-16 1994-06-21 Pioneer Electronic Corporation Satellite radio wave capturing method for a global positioning system (GPS) receiver
US5379224A (en) * 1991-11-29 1995-01-03 Navsys Corporation GPS tracking system
US5402347A (en) * 1993-07-22 1995-03-28 Trimble Navigation Limited Satellite search methods for improving time to first fix in a GPS receiver
US5416712A (en) * 1993-05-28 1995-05-16 Trimble Navigation Limited Position and velocity estimation system for adaptive weighting of GPS and dead-reckoning information
US5420593A (en) * 1993-04-09 1995-05-30 Trimble Navigation Limited Method and apparatus for accelerating code correlation searches in initial acquisition and doppler and code phase in re-acquisition of GPS satellite signals
US5504684A (en) * 1993-12-10 1996-04-02 Trimble Navigation Limited Single-chip GPS receiver digital signal processing and microcomputer
US5519403A (en) * 1993-11-29 1996-05-21 Motorola, Inc. Global positioning system communications multi-interface
US5535432A (en) * 1994-09-14 1996-07-09 Ericsson Ge Mobile Communications Inc. Dual-mode satellite/cellular phone with a frequency synthesizer
US5592173A (en) * 1994-07-18 1997-01-07 Trimble Navigation, Ltd GPS receiver having a low power standby mode
US5625668A (en) * 1994-04-12 1997-04-29 Trimble Navigation Limited Position reporting cellular telephone
US5761456A (en) * 1996-04-03 1998-06-02 Trimble Navigation Limited Processor device having automatic bus sizing
US5781156A (en) * 1995-10-09 1998-07-14 Snaptrack, Inc. GPS receiver and method for processing GPS signals
US5786789A (en) * 1994-11-14 1998-07-28 Trimble Navigation Limited GPS and cellphone unit having add-on modules
US5864315A (en) * 1997-04-07 1999-01-26 General Electric Company Very low power high accuracy time and frequency circuits in GPS based tracking units
US5877725A (en) * 1997-03-06 1999-03-02 Trimble Navigation Limited Wide augmentation system retrofit receiver
US5877724A (en) * 1997-03-25 1999-03-02 Trimble Navigation Limited Combined position locating and cellular telephone system with a single shared microprocessor
US5883594A (en) * 1997-02-20 1999-03-16 Trimble Navigation Limited GPS receiver using a message system for reducing power consumption
US5884214A (en) * 1996-09-06 1999-03-16 Snaptrack, Inc. GPS receiver and method for processing GPS signals
US5889474A (en) * 1992-05-18 1999-03-30 Aeris Communications, Inc. Method and apparatus for transmitting subject status information over a wireless communications network
US5903654A (en) * 1997-08-06 1999-05-11 Rockwell Science Center, Inc. Method and apparatus for eliminating ionospheric delay error in global positioning system signals
US5907809A (en) * 1994-01-11 1999-05-25 Ericsson Inc. Position determination using multiple base station signals
US5917444A (en) * 1995-05-22 1999-06-29 Trimble Navigation Ltd. Reduction of time to first fix in an SATPS receiver
US5920283A (en) * 1997-05-09 1999-07-06 Conexant Systems, Inc. Receiver engine for global positioning system
US5923703A (en) * 1996-05-20 1999-07-13 Pon; Rayman Variable suppression of multipath signal effects
US5926131A (en) * 1996-09-11 1999-07-20 Seiko Instruments Inc. GPS receiving apparatus
US6016119A (en) * 1995-10-09 2000-01-18 Snaptrack, Inc. Method and apparatus for determining the location of an object which may have an obstructed view of the sky
US6034963A (en) * 1996-10-31 2000-03-07 Iready Corporation Multiple network protocol encoder/decoder and data processor
US6041222A (en) * 1997-09-08 2000-03-21 Ericsson Inc. Systems and methods for sharing reference frequency signals within a wireless mobile terminal between a wireless transceiver and a global positioning system receiver
US6040798A (en) * 1995-10-24 2000-03-21 International Mobile Satellite Organization Satellite radiodetermination
US6047017A (en) * 1996-04-25 2000-04-04 Cahn; Charles R. Spread spectrum receiver with multi-path cancellation
US6052081A (en) * 1997-02-03 2000-04-18 Snaptrack, Inc. Method and apparatus for satellite positioning system based time measurement
US6061018A (en) * 1998-05-05 2000-05-09 Snaptrack, Inc. Method and system for using altitude information in a satellite positioning system
US6064336A (en) * 1995-10-09 2000-05-16 Snaptrack, Inc. GPS receiver utilizing a communication link
US6067614A (en) * 1995-09-01 2000-05-23 Sony Corporation Integrated RISC processor and GPS receiver
US6078290A (en) * 1998-01-06 2000-06-20 Trimble Navigation Limited User-controlled GPS receiver
US6178195B1 (en) * 1998-05-14 2001-01-23 Motorola, Inc. Method and apparatus for detecting spread spectrum signals using a signal from a secondary source
US6185427B1 (en) * 1996-09-06 2001-02-06 Snaptrack, Inc. Distributed satellite position system processing and application network
US6192070B1 (en) * 1998-01-02 2001-02-20 Mitsubishi Electric Research Laboratories, Inc. Universal modem for digital video, audio and data communications
US6208291B1 (en) * 1998-05-29 2001-03-27 Snaptrack, Inc. Highly parallel GPS correlator system and method
US6208290B1 (en) * 1996-03-08 2001-03-27 Snaptrack, Inc. GPS receiver utilizing a communication link
US6215441B1 (en) * 1997-04-15 2001-04-10 Snaptrack, Inc. Satellite positioning reference system and method
US6215442B1 (en) * 1997-02-03 2001-04-10 Snaptrack, Inc. Method and apparatus for determining time in a satellite positioning system
US6236354B1 (en) * 1998-07-02 2001-05-22 Snaptrack, Inc. Reducing satellite signal interference in a global positioning system receiver
US6259399B1 (en) * 1995-10-09 2001-07-10 Snaptrack, Inc. GPS receivers and garments containing GPS receivers and methods for using these GPS receivers
US6266612B1 (en) * 1996-10-24 2001-07-24 Trimble Navigation Limited Position based personal digital assistant
US6377209B1 (en) * 1997-02-03 2002-04-23 Snaptrack, Inc. Method and apparatus for satellite positioning system (SPS) time measurement
US6389359B1 (en) * 2000-07-12 2002-05-14 Links Point, Inc. Methods for automatically detecting GPS hardware
US6408196B2 (en) * 1998-07-02 2002-06-18 Snaptrack, Inc. Method and apparatus for providing reserve power in a cellular telephone
US6411254B1 (en) * 1997-04-15 2002-06-25 Snaptrack, Inc. Satellite positioning reference system and method
US6411892B1 (en) * 2000-07-13 2002-06-25 Global Locate, Inc. Method and apparatus for locating mobile receivers using a wide area reference network for propagating ephemeris
US6414987B1 (en) * 1997-04-04 2002-07-02 Trimble Navigation, Ltd. Code multipath estimation for weighted or modified tracking
US6417801B1 (en) * 2000-11-17 2002-07-09 Global Locate, Inc. Method and apparatus for time-free processing of GPS signals
US6510387B2 (en) * 1999-04-23 2003-01-21 Global Locate, Inc. Correction of a pseudo-range model from a GPS almanac
US6526340B1 (en) * 1999-12-21 2003-02-25 Spx Corporation Multi-vehicle communication interface
US6567413B1 (en) * 2001-05-18 2003-05-20 Network Elements, Inc. Optical networking module including protocol processing and unified software control
US6593878B2 (en) * 2001-06-25 2003-07-15 Intel Corporation Integrated network interface card and global positioning system receiver
US7236500B1 (en) * 2000-12-19 2007-06-26 Intel Corporation Demodulation of multi-user, multi-protocol data in a reconfigurable datapath

Family Cites Families (54)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4426712A (en) * 1981-05-22 1984-01-17 Massachusetts Institute Of Technology Correlation system for global position receiver
US4785463A (en) 1985-09-03 1988-11-15 Motorola, Inc. Digital global positioning system receiver
US4701934A (en) 1985-09-03 1987-10-20 Motorola, Inc. Method of doppler searching in a digital GPS receiver
US4890233A (en) 1986-10-27 1989-12-26 Pioneer Electronic Corporation Vehicle bearing detection and data processing methods applicable to vehicle navigation system
JP2666454B2 (en) * 1989-01-24 1997-10-22 富士通株式会社 Wireless automatic alarm transfer system
US5043736B1 (en) * 1990-07-27 1994-09-06 Cae Link Corp Cellular position location system
KR940009235B1 (en) 1990-09-12 1994-10-01 시끼 모리야 On-board vehicle position detector
US5347284A (en) 1991-02-28 1994-09-13 Texas Instruments Incorporated System and method for a digital navigation satellite receiver
US5343209A (en) * 1992-05-07 1994-08-30 Sennott James W Navigation receiver with coupled signal-tracking channels
JP3283913B2 (en) * 1992-08-20 2002-05-20 アイシン精機株式会社 Gps receiving device
DE4236982A1 (en) * 1992-11-02 1994-05-05 Philips Patentverwaltung Cellular mobile radio system
US5345244A (en) 1993-01-12 1994-09-06 Trimble Navigation Limited Cordless SPS smart antenna device
US5347536A (en) 1993-03-17 1994-09-13 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Multipath noise reduction for spread spectrum signals
US5440313A (en) * 1993-05-27 1995-08-08 Stellar Gps Corporation GPS synchronized frequency/time source
US5936572A (en) * 1994-02-04 1999-08-10 Trimble Navigation Limited Portable hybrid location determination system
US5450344A (en) 1994-04-22 1995-09-12 Trimble Navigation Limited GPS receivers with data ports for the uploading and downloading of absolute position information
US5535278A (en) * 1994-05-02 1996-07-09 Magnavox Electronic Systems Company Global positioning system (GPS) receiver for recovery and tracking of signals modulated with P-code
US5734977A (en) 1994-11-10 1998-03-31 Telefonaktiebolaget Lm Ericsson Fraud detection in radio communications network
US5748651A (en) 1995-05-05 1998-05-05 Trumble Navigation Limited Optimum utilization of pseudorange and range rate corrections by SATPS receiver
US5963582A (en) 1996-05-24 1999-10-05 Leica Geosystems Inc. Mitigation of multipath effects in global positioning system receivers
US6002363A (en) 1996-03-08 1999-12-14 Snaptrack, Inc. Combined GPS positioning system and communications system utilizing shared circuitry
US5945944A (en) 1996-03-08 1999-08-31 Snaptrack, Inc. Method and apparatus for determining time for GPS receivers
US5831574A (en) 1996-03-08 1998-11-03 Snaptrack, Inc. Method and apparatus for determining the location of an object which may have an obstructed view of the sky
US5825327A (en) 1996-03-08 1998-10-20 Snaptrack, Inc. GPS receivers and garments containing GPS receivers and methods for using these GPS receivers
EP1260830B1 (en) * 1995-10-09 2010-09-15 Snaptrack, Inc. A GPS receiver and method for processing GPS signals
US6131067A (en) 1995-10-09 2000-10-10 Snaptrack, Inc. Client-server based remote locator device
US6133874A (en) 1996-03-08 2000-10-17 Snaptrack, Inc. Method and apparatus for acquiring satellite positioning system signals
US5845203A (en) 1996-01-25 1998-12-01 Aertis Cormmunications Remote access application messaging wireless method
US5907578A (en) * 1996-05-20 1999-05-25 Trimble Navigation Weighted carrier phase multipath reduction
US5663735A (en) 1996-05-20 1997-09-02 Trimble Navigation Limited GPS receiver using a radio signal for improving time to first fix
US5828694A (en) 1996-07-01 1998-10-27 Trimble Navigation Limited Determination of multipath tracking error
US5854605A (en) 1996-07-05 1998-12-29 Trimble Navigation Limited GPS receiver using data bit timing to achieve a fast time to first fix
US5943363A (en) * 1996-07-17 1999-08-24 Stanford Telecommunications, Inc. Digital spread spectrum GPS navigation receiver
US5966403A (en) 1996-07-19 1999-10-12 Trimble Navigation Limited Code multipath error estimation using weighted correlations
US5995042A (en) 1997-01-02 1999-11-30 Motorola, Inc. Spoofer detection power management for GPS receivers
US5987381A (en) 1997-03-11 1999-11-16 Visteon Technologies, Llc Automobile navigation system using remote download of data
US5987016A (en) 1997-11-04 1999-11-16 Motorola, Inc. Method and apparatus for tracking a communication signal in a wireless communication system
US6107960A (en) * 1998-01-20 2000-08-22 Snaptrack, Inc. Reducing cross-interference in a combined GPS receiver and communication system
US5977909A (en) 1998-03-13 1999-11-02 General Electric Company Method and apparatus for locating an object using reduced number of GPS satellite signals or with improved accuracy
US6002362A (en) 1998-04-20 1999-12-14 Caterpillar Inc. Apparatus and method for receiving position and control signals by a mobile machine
US5999124A (en) 1998-04-22 1999-12-07 Snaptrack, Inc, Satellite positioning system augmentation with wireless communication signals
US6104338A (en) * 1998-05-04 2000-08-15 Snaptrack, Inc. Method and apparatus for operating a satellite positioning system receiver
US5982324A (en) 1998-05-14 1999-11-09 Nortel Networks Corporation Combining GPS with TOA/TDOA of cellular signals to locate terminal
US6133873A (en) 1998-06-03 2000-10-17 Krasner; Norman F. Method and apparatus for adaptively processing GPS signals in a GPS receiver
JP2002529745A (en) * 1998-11-11 2002-09-10 サムソン・エレクトロニクス・カンパニー・リミテッド Digital correlator of the receiver of the satellite signal of the radio navigation system
US6829534B2 (en) * 1999-04-23 2004-12-07 Global Locate, Inc. Method and apparatus for performing timing synchronization
US6313787B1 (en) * 1999-11-12 2001-11-06 Motorola, Inc. Method and apparatus for assisted GPS protocol
US6282231B1 (en) * 1999-12-14 2001-08-28 Sirf Technology, Inc. Strong signal cancellation to enhance processing of weak spread spectrum signal
US6901260B1 (en) * 2000-03-03 2005-05-31 Lucent Technologies Inc. Differential GPS and/or glonass with wireless communications capability
US6873288B2 (en) * 2000-06-14 2005-03-29 Stephen B. Heppe Enhanced GNSS receiver
DE60144522D1 (en) * 2000-08-24 2011-06-09 Sirf Tech Inc Device for reducing auto-correlation and cross-correlation with weak CDMA signals
US6429814B1 (en) * 2000-11-17 2002-08-06 Global Locate, Inc. Method and apparatus for enhancing a global positioning system with terrain model
FR2843638B1 (en) * 2002-08-13 2004-10-22 Thales Sa satellite positioning receiver with correction of inter-correlation errors
WO2004031798A9 (en) * 2002-10-01 2004-08-19 Sirf Tech Inc Fast search gps receiver

Patent Citations (101)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4445118A (en) * 1981-05-22 1984-04-24 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Navigation system and method
US4462712A (en) * 1981-07-16 1984-07-31 Quality Mat Company Method and apparatus for a construction site flooring system
US4463357A (en) * 1981-11-17 1984-07-31 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Method and apparatus for calibrating the ionosphere and application to surveillance of geophysical events
US5014066B1 (en) * 1982-03-01 1996-01-30 Western Atlas Int Inc System for simultaneously deriving position information from a plurality of satellite transmissions
US4667203A (en) * 1982-03-01 1987-05-19 Aero Service Div, Western Geophysical Method and system for determining position using signals from satellites
US5014066A (en) * 1982-03-01 1991-05-07 Western Atlas International, Inc. System for simultaneously deriving position information from a plurality of satellite transmissions
US4894662A (en) * 1982-03-01 1990-01-16 Western Atlas International, Inc. Method and system for determining position on a moving platform, such as a ship, using signals from GPS satellites
US4809005A (en) * 1982-03-01 1989-02-28 Western Atlas International, Inc. Multi-antenna gas receiver for seismic survey vessels
US4578678A (en) * 1983-11-14 1986-03-25 The United States Of America As Represented By The United States National Aeronautics And Space Administration High dynamic global positioning system receiver
US4754465A (en) * 1984-05-07 1988-06-28 Trimble Navigation, Inc. Global positioning system course acquisition code receiver
US4821294A (en) * 1987-07-08 1989-04-11 California Institute Of Technology Digital signal processor and processing method for GPS receivers
US4847862A (en) * 1988-04-07 1989-07-11 Trimble Navigation, Ltd. Global positioning system course acquisition code receiver
US4928106A (en) * 1988-07-14 1990-05-22 Ashtech Telesis, Inc. Global positioning system receiver with improved radio frequency and digital processing
US5108334A (en) * 1989-06-01 1992-04-28 Trimble Navigation, Ltd. Dual down conversion GPS receiver with single local oscillator
US5036329A (en) * 1989-11-22 1991-07-30 Pioneer Electronic Corporation GPS satellite signal tracking method for GPS receivers
US4998111A (en) * 1989-11-27 1991-03-05 Motorola, Inc. CPS transform correlation receiver and method
US5089822A (en) * 1990-02-13 1992-02-18 Avion Systems, Inc. Interrogation signal processor for air traffic control communications
US5111150A (en) * 1990-09-26 1992-05-05 Garmin Corporation Precision phase shift system
US5101416A (en) * 1990-11-28 1992-03-31 Novatel Comunications Ltd. Multi-channel digital receiver for global positioning system
US5134407A (en) * 1991-04-10 1992-07-28 Ashtech Telesis, Inc. Global positioning system receiver digital processing technique
US5293170A (en) * 1991-04-10 1994-03-08 Ashtech Inc. Global positioning system receiver digital processing technique
US5225842A (en) * 1991-05-09 1993-07-06 Navsys Corporation Vehicle tracking system employing global positioning system (gps) satellites
US5202829A (en) * 1991-06-10 1993-04-13 Trimble Navigation Limited Exploration system and method for high-accuracy and high-confidence level relative position and velocity determinations
US5311195A (en) * 1991-08-30 1994-05-10 Etak, Inc. Combined relative and absolute positioning method and apparatus
US5202694A (en) * 1991-09-10 1993-04-13 Trimble Navigation P-code generation
US5379224A (en) * 1991-11-29 1995-01-03 Navsys Corporation GPS tracking system
US5282228A (en) * 1991-12-09 1994-01-25 Novatel Communications Ltd. Timing and automatic frequency control of digital receiver using the cyclic properties of a non-linear operation
US5313069A (en) * 1991-12-31 1994-05-17 Trimble Navigation Distance measuring system of an extendable strip having light reflecting and non-reflecting polygons
US5219067A (en) * 1992-02-04 1993-06-15 Trimble Navigation Limited Keyboard pad structure for electronic devices
US5323322A (en) * 1992-03-05 1994-06-21 Trimble Navigation Limited Networked differential GPS system
US5187450A (en) * 1992-03-13 1993-02-16 Trimble Navigation Limited Voltage controlled oscillator suitable for complete implementation within a semiconductor integrated circuit
US5323164A (en) * 1992-03-16 1994-06-21 Pioneer Electronic Corporation Satellite radio wave capturing method for a global positioning system (GPS) receiver
US5313457A (en) * 1992-04-14 1994-05-17 Trimble Navigation Limited Code position modulation system and method for multiple user satellite communications
US5321799A (en) * 1992-04-17 1994-06-14 Proxim, Inc. Signalling transition control in a modulated-signal communications system
US5223844B1 (en) * 1992-04-17 2000-01-25 Auto Trac Inc Vehicle tracking and security system
US5223844A (en) * 1992-04-17 1993-06-29 Auto-Trac, Inc. Vehicle tracking and security system
US5889474A (en) * 1992-05-18 1999-03-30 Aeris Communications, Inc. Method and apparatus for transmitting subject status information over a wireless communications network
US5306971A (en) * 1992-07-23 1994-04-26 Proxim, Inc. Binary controlled digital tapped delay line
US5296861A (en) * 1992-11-13 1994-03-22 Trimble Navigation Limited Method and apparatus for maximum likelihood estimation direct integer search in differential carrier phase attitude determination systems
US5311197A (en) * 1993-02-01 1994-05-10 Trimble Navigation Limited Event-activated reporting of vehicle location
US5319374A (en) * 1993-02-02 1994-06-07 Trimble Navigation Limited Precise universal time for vehicles
US5311149A (en) * 1993-03-12 1994-05-10 Trimble Navigation Limited Integrated phase locked loop local oscillator
US5420593A (en) * 1993-04-09 1995-05-30 Trimble Navigation Limited Method and apparatus for accelerating code correlation searches in initial acquisition and doppler and code phase in re-acquisition of GPS satellite signals
US5416712A (en) * 1993-05-28 1995-05-16 Trimble Navigation Limited Position and velocity estimation system for adaptive weighting of GPS and dead-reckoning information
US5402347A (en) * 1993-07-22 1995-03-28 Trimble Navigation Limited Satellite search methods for improving time to first fix in a GPS receiver
US5519403A (en) * 1993-11-29 1996-05-21 Motorola, Inc. Global positioning system communications multi-interface
US5504684A (en) * 1993-12-10 1996-04-02 Trimble Navigation Limited Single-chip GPS receiver digital signal processing and microcomputer
US5907809A (en) * 1994-01-11 1999-05-25 Ericsson Inc. Position determination using multiple base station signals
US5625668A (en) * 1994-04-12 1997-04-29 Trimble Navigation Limited Position reporting cellular telephone
US5592173A (en) * 1994-07-18 1997-01-07 Trimble Navigation, Ltd GPS receiver having a low power standby mode
US5535432A (en) * 1994-09-14 1996-07-09 Ericsson Ge Mobile Communications Inc. Dual-mode satellite/cellular phone with a frequency synthesizer
US5786789A (en) * 1994-11-14 1998-07-28 Trimble Navigation Limited GPS and cellphone unit having add-on modules
US5917444A (en) * 1995-05-22 1999-06-29 Trimble Navigation Ltd. Reduction of time to first fix in an SATPS receiver
US6067614A (en) * 1995-09-01 2000-05-23 Sony Corporation Integrated RISC processor and GPS receiver
US5874914A (en) * 1995-10-09 1999-02-23 Snaptrack, Inc. GPS receiver utilizing a communication link
US6016119A (en) * 1995-10-09 2000-01-18 Snaptrack, Inc. Method and apparatus for determining the location of an object which may have an obstructed view of the sky
US6064336A (en) * 1995-10-09 2000-05-16 Snaptrack, Inc. GPS receiver utilizing a communication link
US6421002B2 (en) * 1995-10-09 2002-07-16 Snaptrack, Inc. GPS receiver utilizing a communication link
US5781156A (en) * 1995-10-09 1998-07-14 Snaptrack, Inc. GPS receiver and method for processing GPS signals
US6259399B1 (en) * 1995-10-09 2001-07-10 Snaptrack, Inc. GPS receivers and garments containing GPS receivers and methods for using these GPS receivers
US6542821B2 (en) * 1995-10-09 2003-04-01 Snaptrack, Inc. GPS receiver and method for processing GPS signals
US6040798A (en) * 1995-10-24 2000-03-21 International Mobile Satellite Organization Satellite radiodetermination
US6208290B1 (en) * 1996-03-08 2001-03-27 Snaptrack, Inc. GPS receiver utilizing a communication link
US5761456A (en) * 1996-04-03 1998-06-02 Trimble Navigation Limited Processor device having automatic bus sizing
US6047017A (en) * 1996-04-25 2000-04-04 Cahn; Charles R. Spread spectrum receiver with multi-path cancellation
US5923703A (en) * 1996-05-20 1999-07-13 Pon; Rayman Variable suppression of multipath signal effects
US6185427B1 (en) * 1996-09-06 2001-02-06 Snaptrack, Inc. Distributed satellite position system processing and application network
US5884214A (en) * 1996-09-06 1999-03-16 Snaptrack, Inc. GPS receiver and method for processing GPS signals
US5926131A (en) * 1996-09-11 1999-07-20 Seiko Instruments Inc. GPS receiving apparatus
US6266612B1 (en) * 1996-10-24 2001-07-24 Trimble Navigation Limited Position based personal digital assistant
US6034963A (en) * 1996-10-31 2000-03-07 Iready Corporation Multiple network protocol encoder/decoder and data processor
US6377209B1 (en) * 1997-02-03 2002-04-23 Snaptrack, Inc. Method and apparatus for satellite positioning system (SPS) time measurement
US6052081A (en) * 1997-02-03 2000-04-18 Snaptrack, Inc. Method and apparatus for satellite positioning system based time measurement
US6583757B2 (en) * 1997-02-03 2003-06-24 Snaptrack, Inc. Method and apparatus for satellite positioning system (SPS) time measurement
US6239742B1 (en) * 1997-02-03 2001-05-29 Snaptrack, Inc. Method and apparatus for satellite positioning system based time measurement
US6215442B1 (en) * 1997-02-03 2001-04-10 Snaptrack, Inc. Method and apparatus for determining time in a satellite positioning system
US5883594A (en) * 1997-02-20 1999-03-16 Trimble Navigation Limited GPS receiver using a message system for reducing power consumption
US5877725A (en) * 1997-03-06 1999-03-02 Trimble Navigation Limited Wide augmentation system retrofit receiver
US5877724A (en) * 1997-03-25 1999-03-02 Trimble Navigation Limited Combined position locating and cellular telephone system with a single shared microprocessor
US6414987B1 (en) * 1997-04-04 2002-07-02 Trimble Navigation, Ltd. Code multipath estimation for weighted or modified tracking
US5864315A (en) * 1997-04-07 1999-01-26 General Electric Company Very low power high accuracy time and frequency circuits in GPS based tracking units
US6215441B1 (en) * 1997-04-15 2001-04-10 Snaptrack, Inc. Satellite positioning reference system and method
US6411254B1 (en) * 1997-04-15 2002-06-25 Snaptrack, Inc. Satellite positioning reference system and method
US5920283A (en) * 1997-05-09 1999-07-06 Conexant Systems, Inc. Receiver engine for global positioning system
US5903654A (en) * 1997-08-06 1999-05-11 Rockwell Science Center, Inc. Method and apparatus for eliminating ionospheric delay error in global positioning system signals
US6041222A (en) * 1997-09-08 2000-03-21 Ericsson Inc. Systems and methods for sharing reference frequency signals within a wireless mobile terminal between a wireless transceiver and a global positioning system receiver
US6192070B1 (en) * 1998-01-02 2001-02-20 Mitsubishi Electric Research Laboratories, Inc. Universal modem for digital video, audio and data communications
US6078290A (en) * 1998-01-06 2000-06-20 Trimble Navigation Limited User-controlled GPS receiver
US6061018A (en) * 1998-05-05 2000-05-09 Snaptrack, Inc. Method and system for using altitude information in a satellite positioning system
US6178195B1 (en) * 1998-05-14 2001-01-23 Motorola, Inc. Method and apparatus for detecting spread spectrum signals using a signal from a secondary source
US6208291B1 (en) * 1998-05-29 2001-03-27 Snaptrack, Inc. Highly parallel GPS correlator system and method
US6236354B1 (en) * 1998-07-02 2001-05-22 Snaptrack, Inc. Reducing satellite signal interference in a global positioning system receiver
US6408196B2 (en) * 1998-07-02 2002-06-18 Snaptrack, Inc. Method and apparatus for providing reserve power in a cellular telephone
US6510387B2 (en) * 1999-04-23 2003-01-21 Global Locate, Inc. Correction of a pseudo-range model from a GPS almanac
US6526340B1 (en) * 1999-12-21 2003-02-25 Spx Corporation Multi-vehicle communication interface
US6389359B1 (en) * 2000-07-12 2002-05-14 Links Point, Inc. Methods for automatically detecting GPS hardware
US6411892B1 (en) * 2000-07-13 2002-06-25 Global Locate, Inc. Method and apparatus for locating mobile receivers using a wide area reference network for propagating ephemeris
US6417801B1 (en) * 2000-11-17 2002-07-09 Global Locate, Inc. Method and apparatus for time-free processing of GPS signals
US7236500B1 (en) * 2000-12-19 2007-06-26 Intel Corporation Demodulation of multi-user, multi-protocol data in a reconfigurable datapath
US6567413B1 (en) * 2001-05-18 2003-05-20 Network Elements, Inc. Optical networking module including protocol processing and unified software control
US6593878B2 (en) * 2001-06-25 2003-07-15 Intel Corporation Integrated network interface card and global positioning system receiver

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090073037A1 (en) * 2005-06-08 2009-03-19 Nxp B.V. Gps processing arrangement
US7619560B2 (en) * 2005-06-08 2009-11-17 Nxp B.V. GPS processing arrangement
US10020968B1 (en) * 2015-03-18 2018-07-10 National Technology & Engineering Solutions Of Sandia, Llc Coherent radar receiver that comprises a sigma delta modulator

Also Published As

Publication number Publication date Type
US20060214846A1 (en) 2006-09-28 application
US7365680B2 (en) 2008-04-29 grant

Similar Documents

Publication Publication Date Title
US6052081A (en) Method and apparatus for satellite positioning system based time measurement
US6442672B1 (en) Method for dynamic allocation and efficient sharing of functional unit datapaths
US20140062782A1 (en) Method and System for Calibrating Group Delay Errors in a Combined GPS and GLONASS Receiver
US20030118081A1 (en) Programmable modem apparatus for transmitting and receiving digital data, design method and use method for the modem
US7375682B1 (en) Always-on satellite positioning receiver
Ziedan GNSS receivers for weak signals
US20030003908A1 (en) Method and apparatus for storing data in flash memory
US6278404B1 (en) Global positioning system satellite selection method
US7561101B1 (en) Last known position reporting for always-on global positioning system receiver
US20040008660A1 (en) Dedicated device for automatically accessing wireless internet network and supplying wireless packet data-based indoor-capable GPS locations
US20060027644A1 (en) IC card and IC card system having suspend/resume functions
US20030167345A1 (en) Communications bridge between a vehicle information network and a remote system
US5448773A (en) Long life portable global position system receiver
US7348921B2 (en) GPS receiver using stored navigation data bits for a fast determination of GPS clock time
US7103785B2 (en) Method and apparatus for power management event wake up
US20050083230A1 (en) Advanced power management for satellite positioning system
US5847680A (en) GPS receiver having fast resolution of carrier phase ambiguity
US6954147B1 (en) Method and system for providing protection against theft and loss of a portable computer system
US20100149033A1 (en) Method and system for power management for a frequency synthesizer in a gnss receiver chip
US20090168843A1 (en) Power-saving receiver circuits, systems and processes
US6384777B1 (en) User-controlled GPS receiver
US20100171659A1 (en) Position engine (pe) feedback to improve gnss receiver performance
US6912242B2 (en) Low power RF receiver with redistribution of synchronisation tasks
WO1998009181A1 (en) Combination of a gps receiver and a telecommunications apparatus
WO2009074654A1 (en) Gnss method and receiver with camera aid

Legal Events

Date Code Title Description
AS Assignment

Owner name: SIRF TECHNOLOGY, INC., CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:VANTALON, NICOLAS;PENG, LEON K.;GULLIVER, GREGORY B.;REEL/FRAME:018196/0136

Effective date: 20010718

AS Assignment

Owner name: CSR TECHNOLOGY INC., CALIFORNIA

Free format text: CHANGE OF NAME;ASSIGNOR:SIRF TECHNOLOGY, INC.;REEL/FRAME:027437/0324

Effective date: 20101119