Sirf Technology, Inc.

Hughes Aircraft Company

Csr Technology Inc.

Sirf Technology Holdings, Inc.

Robert Tso

Noshir Behli Dubash

Richard McConnell

Steve Gronemeyer

Lawrence M Burns

Tao Zhang

Ray Michael Herman

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 interface and a data interface. The message interface supports transmission of power control messages to the RF processing section to provide detailed control over activation or de-activation of individual blocks of hardware circuitry in the RF processing section.

Serial radio frequency to baseband interface with power control

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.

Serial radio frequency to baseband interface with programmable clock

A GPS RF Front End IC using a single conversion stage, which is immune from self jamming from clock signal harmonics generated internally or from dominant clock signal harmonics generated externally by the subsequent baseband GPS processor which uses a clock of 48&#x25cf;fo for GPS processing. The improved frequency plan reduces the problems of interference when the integration of the RF and Baseband functions is required in the form of a single-chip, or as 2 individual chips on a common substrate.

GPS RF front end IC with frequency plan for improved integrability

In a system and method for simultaneously receiving or switching between dual frequency carrier signals in a GPS receiver, the GPS receiver is adapted to utilize different harmonics of a sub-harmonic frequency generator, which may include a lower frequency voltage controlled oscillator (VCO) to detect the L1 and L2 GPS carriers. A sub-harmonic mixer may be used to simultaneously down convert the L1 and L2 signals to a lower intermediate frequency (IF). A second mixer may be an image reject (IR) mixer used to separate the downconverted L1 and L2 signals. This mixer may be configured to simultaneously monitor the L1 and L2 signals, or to switch between the L1 and L2 signals. High frequency switching is not required of the radio frequency (RF) input or local oscillator signals, and simultaneous L1 and L2 reception is enabled without and 3 dB image noise degradation. This system and method minimizes the RF components and power dissipation in a dual frequency GPS receiver, while optimizing the functionality and performance.

L1/L2 GPS receiver

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.

RF converter with multiple mode frequency synthesizer compatible with a 48 Fo GPS baseband processor

A highly integrated GPS RF Front End, an interface thereto, and a GPS receiver that incorporates the GPS RF front end, which uses a single conversion stage employing an image rejection mixer stage to eliminate the need for an image reject RF bandpass filter. Also a relatively high sample rate A/D is employed which allows a timeless monolithic IF Filter to be used. The disclosure also discusses a GPS Front End topology that is easily integrated from industry standard building blocks. With the broad variation in potential receiver designs, the present invention includes some specific receiver topologies that lend themselves to a high level of integration. The specific designs presented here are comprised of industry standard building blocks and functions that have been described elsewhere in the related art.

Monolithic GPS RF front end integrated circuit

A GPS RF Front End IC containing a Programmable Frequency Synthesizer is disclosed. The GPS RF front end IC having a programmable frequency synthesizer allows a relatively fixed internal frequency plan while able to use a number of different reference frequencies provided by the host platform, which can be a wireless phone, or other such device, which can provide an accurate reference frequency signal.

GPS RF front end IC with programmable frequency synthesizer for use in wireless phones

A fractional-R synthesizer having a divider with rational increments and configurable in rational steps able to generate a plurality of frequencies in rational increments from a reference frequency. A voltage-controlled oscillator frequency (f) is related to the reference frequency (f) by: f=f/R, where Ris the average value of the rational divide value 'R' over a large number of reference cycles.

Fractional-R frequency synthesizer

A highly integrated GPS RF Front End which uses a single conversion stage employs an image rejection mixer stage to eliminate the need for an image reject RF bandpass filter. Also a relatively high sample rate A/D is employed which allows a timeless monolitic IF Filter to be used. The disclosure also discusses a GPS Front End topology that is easily integrated from industry standard building blocks. With the broad variation in potential receiver designs, the present invention includes some specific receiver topologies that lend themselves to a high level of integration. The specific designs presented here are comprised of industry standard building blocks and functions that have been described elsewhere in the related art.

A GPS RF Front End IC using a single conversion stage, which is immune from self jamming from clock signal harmonics generated internally or from dominant clock signal harmonics generated externally by the subsequent baseband GPS processor which uses a clock of 48&#x2022;fo for GPS processing. The improved frequency plan reduces the problems of interference when the integration of the RF and Baseband functions is required in the form of a single-chip, or as 2 individual chips on a common substrate.

In a system and method for simultaneously receiving or switching between dual frequency carrier signals in a GPS receiver, the GPS receiver is adapted to utilize different harmonics of a sub-harmonic frequency generator, which may include a lower frequency voltage controlled oscillator (VCO) to detect the L1 and L2 GPS carriers. A sub-harmonic mixer may be used to simultaneously down convert the L1 and L2 signals to a lower intermediate frequency (IF). A second mixer may be an image reject (IR) mixer used to separate the downconverted L1 and L2 signals. This mixer may be configured to simultaneously monitor the L1 and L2 signals, or to switch between the L1 and L2 signals. High frequency switching is not required of the radio frequency (RF) input or local oscillator signals, and simultaneous L1 and L2 reception is enabled without a 3 dB image noise degradation. This system and method minimizes the RF components and power dissipation in a dual frequency GPS receiver, while optimizing the functionality and performance.

A method and apparatus for minimizing the interference between wireless transmissions and a proximately located or co-located GPS receiver is disclosed. By feedforward of a phase and amplitude adjusted version of the transmitted signal and combining said signal with the composite signal at the input of the GPS receiver, the GPS receiver sensitivity degradation is reduced or eliminated in the case of perfect cancellation, and the GPS receiver is not jammed by the wireless transmissions. The invention allows a single antenna to be implemented for GPS reception and wireless transmission and reception without unduly complicating the diplexing/filtering network required to separate the multiple signals being transmitted and/or received by the single antenna.

Method and apparatus for reducing GPS receiver jamming during transmission in a wireless receiver

A GPS RF Front End IC containing a Programmable Frequency synthesizer is disclosed. The GPS RF front end IC having a programmable frequency synthesizer allows a relatively fixed internal frequency plan while able to use a number of different reference frequencies provided by the host platform, which can be a wireless phone, or other such device, which can provide an accurate reference frequency signal.

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South San Gabriel, CA, United States of America

Robert Tso