1987 results about "Deconvolution" patented technology

Multiple Steiner codes are transmitted as bursts from multiple base stations (182, 184, 186) having one or more transmit elements (174, 176, 178, 180), with successive bursts providing an extended training sequence for use in channel estimation at an addressed unit (172), such as a mobile handset. Accurate channel estimation is possible through the use of Wiener frequency domain MMSE deconvolution (518) combined with frequency domain spatial decoupling matrices, with quasi-orthogonal pseudo-noise sequences (502, 504, 520, 522) allocated to base stations and their antenna elements. The use of Steiner codes to supplement Wiener frequency domain MMSE deconvolution and frequency domain spatial decoupling results in the possibility of allocating only a single training sequence to each base station provided that the training sequence is of sufficient length to encompass all multiple time-translated channel impulse responses (H). Estimates may be refined iteratively by minimising the MS error of demodulated pilot symbols. Estimates may also be refined by removing taps from the impulse response which are insignificant based on a relatively long-term power-delay profile for the channel.

A reader obtains image data corresponding to an image of optically encoded information that is received via a lens unit that causes controlled spherical aberration blurring that is precisely known. The reader may perform deconvolution processing on the image data to render it decodable. The deconvolution processing may implement a Weiner filter that uses data corresponding to a near-field point spread function of the lens unit. The depth of field of the reader is greater than that of conventional reader in all lighting conditions.

An extended depth of field is achieved by a computational imaging system that combines a multifocal imaging subsystem for producing a purposefully blurred intermediate image with a digital processing subsystem for producing a recovered image having an extended depth of field. The multifocal imaging system preferably exhibits spherical aberration as the dominant feature of the purposeful blur. A central obscuration of the multifocal imaging subsystem renders point-spread functions of object points more uniform over a range of object distances. An iterative digital deconvolution algorithm for converting the intermediate image into the recovered image contains a metric parameter that speeds convergence, avoids stagnations, and enhances image quality.

A rapid iris acquisition, tracking, and imaging system can be used at longer standoff distances and over larger capture volumes, without the active cooperation of subjects. Light illuminates the subjects' eyes and a high resolution camera captures images of the irises. The images of the irises are processed by a post processing module to improve their quality. In one approach, the point spread function of the image capture subsystem is estimated using glint reflections from the eye, and the estimated point spread function is used in deconvolution to increase the resolution of the iris images. The post processed iris images have sufficient resolution to be used for biometric identification.

A smart camera system provides focused images to an operator at a host computer by processing digital images at the imaging location prior to sending them to the host computer. The smart camera has a resident digital signal processor for preprocessing digital images prior to transmitting the images to the host. The preprocessing includes image feature extraction and filtering, convolution and deconvolution methods, correction of parallax and perspective image error and image compression. Compression of the digital images in the smart camera at the imaging location permits the transmission of very high resolution color or high resolution grayscale images at real-time frame rates such as 30 frames per second over a high speed serial bus to a host computer or to any other node on the network, including any remote address on the Internet.