Abstract: Presented herein are systems and methods for processing sound signals for use with electronic speech systems. Sound signals are temporally parsed into frames, and the speech system includes a speech codebook having entries corresponding to frame sequences. The system identifies speech sounds in an audio signal using the speech codebook.

Abstract: The invention provides a set of methods and systems for obtaining a synchronized signal in a distributed fashion. The methods and systems described herein allow a node to obtain a periodic signal that would be synchronized with the periodic signal obtained at another node when both nodes follow the same synchronizing procedure, without the need for centralized control of both nodes or the need for all nodes to have coordinated local oscillators. The invention includes beamforming methods and systems for producing a coherent beam at a target location and at a target frequency using the synchronized signal.

Abstract: The invention provides a set of methods and systems for obtaining a synchronized signal in a distributed fashion. The methods and systems described herein allow a node to obtain a periodic signal that would be synchronized with the periodic signal obtained at another node when both nodes follow the same synchronizing procedure, without the need for centralized control of both nodes or the need for all nodes to have coordinated local oscillators. The invention includes beamforming methods and systems for producing a coherent beam at a target location and at a target frequency using the synchronized signal.

Abstract: Presented herein are systems and methods for generating an adaptive noise codebook for use with electronic speech systems. The noise codebook includes a plurality of entries which may be updated based on environmental noise sounds. The speech system includes a speech codebook and the adaptive noise codebook. The system identifies speech sounds in an audio signal using the speech and noise codebooks.

Abstract: A speech analysis system includes a codebook (230) that stores speech spectral parameters corresponding to a speech spectral hypothesis. The speech spectral hypothesis may be combined with a noise spectral hypothesis and the combined hypothesis compared to a sensed signal via a discriminant function (240). The discriminant function may be evaluated using the preconditioned conjugate gradient (PCG) process.

Abstract: Methods and systems for determining characteristics of a Finite Impulse Response system that can include applying a number of identical sets of probe signals to the system and averaging the observed outputs. A discrete Fourier transform (DFT) of the averaged outputs can be obtained and the DFT components can be multiplied by corresponding transformed companion components related to the probe components. The system characteristics can be selected based on computing the inverse DFT of the resulting product components. The probe components can be taken from a circulant matrix of size S×S, or from an inverse DFT of a set of transform components consisting of arbitrary, non-zero, real numbers for first and last components of a partial set and arbitrary, non-zero, complex numbers for other components of the partial set to which the non-zero, complex number components of the partial set are added in reverse order and in complex conjugate.

Abstract: A data communications system, particularly suited for shared or wireless communications channels, capable of accommodating terminals having different throughput capabilites by flexibly allocating cyclically rotated phases of a common code is disclosed. One or more shifts of a cyclic orthogonal code are assigned to a terminal. These codes are preferably cyclically padded to increase their tolerance to arbitrary time shifts, and the resulting codes are used to spread the signals for transmission.