Broadcom Corporation

Rf Micro Devices, Inc.

Other

Andreas Warloe

Charles Abraham

Charles P Norman

Jared Welz

Richard Najarian

Richard Gerald Keegan

Jason Matthew Goldberg

Wayne H Cox

Steve Francis Colborne

Benjamin Imai

Michael J Field

A direct-sequence spread spectrum (DSSS) receiver may be operable to process signal samples in frequency domain utilizing a prime factor fast Fourier transform (FFT) circuit and a pseudorandom noise (PRN) code. The DSSS receiver may be operable to transform the signal samples into FFT signal samples using the prime factor FFT circuit, transform the PRN code into a FFT PRN code using the prime factor FFT circuit and multiply the FFT signal samples with the FFT PRN code using the prime factor FFT circuit. The DSSS receiver may be operable to inversely transform the multiplied FFT signal samples into correlated signal samples using a prime factor inverse FFT (IFFT) implemented by the prime factor FFT circuit. The prime factor FFT circuit may comprise a prime length FFT core, a FFT memory, a register bank, a switch, a multiplier and a FFT controller.

Method and system for efficient DSSS FFT processing employing prime factor decomposition

A global navigation satellite system (GNSS) receiver may be operable to quantize two-dimensional GNSS sample data with an in-phase (I) and quadrature (Q) pair to two-dimensional quantized data with a magnitude and angle pair using the polar quantization, for example, an unrestricted polar quantization. The GNSS receiver may be operable to reduce a size of the two-dimensional quantized data for storage by representing the two-dimensional quantized data by the one-dimensional symbol data. The one-dimensional symbol data may be stored in a random access memory (RAM) for further processing. The I and Q pair associated with the one-dimensional symbol data stored in the RAM may be retrieved and processed by the GNSS receiver using a correlation such as a fast Fourier transform (FFT) correlation.

Method and system for polar quantization for GNSS data

An integrated global navigation satellite system (GNSS) receiver may be operable to decompose GNSS IF signals associated with GPS satellites and/or GLONASS satellites into a constituent narrowband GPS data stream and/or a plurality of constituent narrowband GLONASS data streams utilizing, for example, a GPS IF tuner and/or one or more GLONASS IF tuners. The narrowband GLONASS data streams and/or the narrowband GPS data stream may be processed at reduced sampling rates utilizing a shared sample memory in the integrated GNSS receiver. The narrowband GLONASS data streams and/or the narrowband GPS data stream may be stored in allocated sections of the shared sample memory. The stored narrowband GLONASS data streams and/or the stored narrowband GPS data stream may be processed using a correlation such as a fast Fourier transform (FFT) correlation.

Method and system for integrated glonass and GPS processing

Method and system for integrated GLONASS and GPS processing

A GPS assembly test system and method for a wireless communications device, such as a mobile telephone, having an integrated GPS receiver. The GPS assembly test can be performed without the requirement of external testing equipment. The GPS assembly test activates the wireless communications device transmitter during testing to increase GPS in-band noise. If the GPS receiver components are installed and operating properly, a change in noise is expected and can be detected. Embodiments include test software to initiate the transmitter during testing. Different methods can be used to detect a change in noise density. For example, an expected automatic reduction in gain control to a low noise amplifier (LNA) can be detected when the transmitter is activated. Another example includes setting LNA gain to a fixed gain and detecting expected changes in data generated an analog-to-digital (A/D) converter in response to the increased noise.

Global positioning system (GPS) assembly test using wireless transmission

The address translation logic of the present invention is incorporated in a global positioning system (GPS) receiver and operates to group data in memory based on translating the address from a direct memory access controller. The data includes post-correlated samples of the correlation of a signal with a generated frequency and a generated code having a plurality of time offsets. In general, the address translation logic organizes the data such that each element of the data associated with particular ones of the plurality of time offsets are grouped together in order to improve the efficiency of performing a fast Fourier transform of the data. In addition, the address translation logic allows the transfer of data from correlation circuitry to memory, from the memory to an FFT module, and from the FFT module to the memory using standard DMA controllers.

Address translation logic for use in a GPS receiver

The jammer response circuitry of the present invention operates to control correlation circuitry in a GPS receiver based on an occurrence of a transmission from a wireless transmitter, thereby avoiding performance degradation in th GPS receiver due to interference caused by the transmission. In general, the jammer response circuitry activates a control signal during the transmission, thereby temporarily stopping the operation of the correlation circuitry. More particularly, the accumulation of results of a correlation of a received signal with a generated frequency and a generated code having numerous time offsets is temporarily stopped when the control signal is activated and resumes operation when the control signal is deactivated.

Avoiding interference to a GPS receiver from wireless transmissions by time multiplexing GPS reception

The correlation circuitry of the present invention operates in communication with a controller and transform circuitry to concurrently search a range of frequencies by correlating a received signal from the global positioning system (GPS) with a generated frequency and a generated code at a plurality of time offsets. The output of the correlation circuitry is provided to the transform circuitry, such as fast Fourier transform (FFT) circuitry, that transforms the output of the correlation circuitry. The results from the transformation circuitry are used by a GPS receiver to determine a frequency of the received GPS signal and a time offset associated with a ranging code carried in the received GPS signal.

Using FFT engines to process decorrelated GPS signals to establish frequencies of received signals

The global positioning system (GPS) receiver of the present invention operates to search a range of frequencies by correlating a baseband signal corresponding to a received GPS signal with a generated frequency and a generated code at a plurality of time offsets. Address translation logic operates to group results of the correlation according to the plurality of time offsets by translating addresses received from a direct memory access (DMA) controller in order to improve the efficiency of performing a fast Fourier transform (FFT) on the results of the correlation. The transformed data produced by the FFT process are used by the GPS receiver to determine a frequency of the received GPS signal and a time offset associated with a ranging code carried in the received GPS signal.

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Fountain Valley, CA, United States of America

Andreas Warloe