Abstract: The disclosure relates generally to a method of three dimensional (3D) tomographic volume reconstruction for computed tomography (CT) using vector processors and more specifically to an optimized implementation which pre-computes back projection weights and perspective geometry data associated with a given CT device as down-sampled tables. The down-sampled perspective geometry data and the weight table are interpolated dynamically as part of the volume reconstruction process for an object scanned using the given CT device.

Abstract: The invention provides, in some aspects, methods and apparatus for signal and/or image processing which perform convolution-based filtering utilizing a graphics processing unit (GPU, also called “graphics card”) to compute multiple output pixels at once. This has the advantage of saving memory bandwidth, while leveraging the GPUs vector multiplication and dot product units during the calculation. Related aspects of the invention provide such methods and apparatus in which multiple output pixels are computed simultaneously by using render targets with more than one channel, e.g., an RGBA render target, or multiple render targets, or a combination thereof.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third procesing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third processing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third processing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: A wideband signal generator according to one embodiment of the invention includes a variable frequency source and a direct digital synthesizer. Local oscillators, signal analyzers, modulators, demodulators, and other equipment including one or more such generators are also disclosed.

Abstract: The invention provides, in one aspect, an improved digital data processing system of the type having a plurality of execution resources, including a central processing unit (CPU) and one or more further execution resources (or “components”). The improvement is characterized by a process executing on the central processing unit that selects portions of an applications program and effects their execution on one or more of the further execution resources, while effecting execution of remaining portions of the application on the CPU. The further execution resources, according to related aspects of the invention, can include co-processors, accelerators, controllers or other devices, of the “plug-and-play” variety or otherwise. They may provide specialized functionality for any of fast Fourier transforms, image reconstruction and synthetic aperture radar algorithms, to name a few. Those resources may be disposed locally or remotely with respect to the CPU.

Abstract: The invention provides, in one aspect, an improved digital data processing system of the type having a plurality of execution resources, including a central processing unit (CPU) and one or more further execution resources (or “components”). The improvement is characterized by a process executing on the central processing unit that selects portions of an applications program and effects their execution on one or more of the further execution resources, while effecting execution of remaining portions of the application on the CPU. The further execution resources, according to related aspects of the invention, can include co-processors, accelerators, controllers or other devices, of the “plug-and-play” variety or otherwise. They may provide specialized functionality for any of fast Fourier transforms, image reconstruction and synthetic aperture radar algorithms, to name a few. Those resources may be disposed locally or remotely with respect to the CPU.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third processing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third processing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third procesing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third processing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides improved CDMA, WCDMA (UTMS) or other spread spectrum communication systems of the type that processes one or more spread-spectrum waveforms, each representative of a waveform received from a respective user (or other transmitting device). The improvement is characterized by a first logic element that generates a residual composite spread-spectrum waveform as a function of an arithmetic difference between a composite spread-spectrum waveform for all users (or other transmitters) and an estimated spread-spectrum waveform for each user. It is further characterized by one or more second logic elements that generate, for at least a selected user (or other transmitter), a refined spread-spectrum waveform as a function of a sum of the residual composite spread-spectrum waveform and the estimated spreads-spectrum waveform for that user.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third procesing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides improved CDMA, WCDMA (UTMS) or other spread spectrum communication systems of the type that processes one or more spread-spectrum waveforms, each representative of a waveform received from a respective user (or other transmitting device). The improvement is characterized by a first logic element that generates a residual composite spread-spectrum waveform as a function of an arithmetic difference between a composite spread-spectrum waveform for all users (or other transmitters) and an estimated spread-spectrum waveform for each user. It is further characterized by one or more second logic elements that generate, for at least a selected user (or other transmitter), a refined spread-spectrum waveform as a function of a sum of the residual composite spread-spectrum waveform and the estimated spread-spectrum waveform for that user.

Abstract: The invention provides improvements in reconstructive imaging of the type in which a volume is reconstructed from a series of measured projection images (or other two-dimensional representations) generated by projection of a point x-ray source (or other radiation source), positioned at a distinct focus, through the volume to a plane at which the respective projection image is acquired (“detector plane”). In one aspect, the improvements are with respect to back-projecting a two-dimensional representation lying in the detector plane (representing, for example, a difference between an originally-acquired measured projection image and a subsequently-generated estimate thereof) to generate three-dimensional representation (which can be used, for example, to update an estimate of the volume).

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third procesing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a digital signal processor (“DSP”) that processes user waveforms. The DSP has an associated memory and an associated direct memory access (“DMA”) controller that controls access to that memory. A programmable logic device (“PLD”) is coupled to the DMA controller and configures it to move data relating to user waveform characteristics from the memory to a buffer external to the DSP.

Abstract: The invention provides methods and apparatus for multiple user detection (MUD) processing that have application, for example, in improving the capacity CDMA and other wireless base stations. One aspect of the invention provides a multiprocessor, multiuser detection system for detecting user transmitted symbols in CDMA short-code spectrum waveforms. A first processing element generates a matrix (hereinafter, “gamma matrix”) that represents a correlation between a short-code associated with one user and those associated with one or more other users. A set of second processing elements generates, e.g., from the gamma matrix, a matrix (hereinafter, “R-matrix”) that represents cross-correlations among user waveforms based on their amplitudes and time lags. A third procesing element produces estimates of the user transmitted symbols as a function of the R-matrix.

Abstract: A digital data system employs multiple error protection mechanisms on messages that pass along a link interconnect fabric from one node or device to another node or device. The nodes may be end points (such as processor or storage units), or may be intermediate devices or branch points (such as routers or switches in the interconnect fabric). The interconnect fabric comprises a set of one or more routers, switches, electrical, optical, electroptical or other links along which messages are passed. Messages are packets having a defined format including, e.g., a header portion, typically with source and target addresses, and codes indicating message-type or other information, followed by one or more data or other fields. A first node (“sending” node) of a digital data system as described sends a data transmission comprising one or more message packets to a second node (“receiving” node) over a link of a fabric as described above.