Abstract: A method and apparatus enabling the substantially concurrent operation of multiple decimators within a digitizing measurement device such as a digital storage oscilloscope (DSO), wherein the multiple decimators provide multiple processed sample streams that may be used for a composite presentation of input signal data.

Abstract: An efficient predictor for subjective video quality rating measures processes a reference video and an impaired video corresponding to the reference video in respective processing channels. Each channel applies a contrast sensitivity function from a human vision system model to the respective videos and a contrast discrimination function for self-masking to the output of the contrast sensitivity function. The outputs from the channels are input to a differencing circuit to obtain absolute difference values. The absolute difference values are modified by a global masking factor derived from the output from the reference video channel, and the resulting values are converted into units conforming to a standard quality rating metric.

Abstract: A frequency selective improved directivity of a return loss bridge is achieved by generating a counteractive reflected energy vector to cancel a reflected energy vector caused by imperfections, such as parasitic effects and an unbalanced balun, in the return loss bridge. The counteractive reflected energy vector of equal magnitude, but opposite in phase, to the undesired reflected energy vector may be induced into a transmission path between a test port and a coupled port. An open circuit stub in the transmission path between the test port and the coupled port may be used to provide the counteractive reflected energy vector. Alternatively a path across a coupling resistor in a return loss path coupled from the test port to the coupled port may be used to provide the counteractive reflected energy vector, with PIN diodes in the coupled path being used for tunability if desired.

Abstract: A technique for image alignment with global translation and linear stretch determines translation parameters for three corresponding linearly displaced blocks in a reference image and a corresponding distorted test image. From the differences between the translation parameters for the three blocks the presence of stretch is detected and, if detected, a stretch factor is estimated. The estimated stretch factor is used as a starting point to stretch the reference image to overlap the distorted test image as a refinement process. The resulting refined stretch factor is then used in a reverse stretch process to shrink the distorted test image, and the distorted test image is then aligned with the reference image to obtain picture quality metrics.

Abstract: A method of determining distance to fault of a transient event in a transmission system uses per frequency triggered I and Q data representing voltage and phase of a return signal in the frequency domain. Initially a result set of data entries, one for each discrete frequency in a specified frequency range, is filled with zeros and an initial acquisition set of per frequency I and Q data from the transmission system is used to fill a reference set of data entries. Subsequent acquisitions of per frequency data sets are used to fill a current set of data entries. Between each acquisition of data sets for the current set a comparison is made, entry by entry, between the current set and the reference set, and the data from the current set is used to update the corresponding entry in the result set when the difference exceeds a specified tolerance.

Abstract: A frequency domain analysis system incorporated into time domain measurement instrument has duration and resolution controls that respectively adjust the acquisition time intervals of a waveform record in seconds and adjusts the number of digital data samples over a specified duration. The duration of the acquisition waveform may be controlled using the duration control adjustment, a sample rate adjustment and a record length adjustment. The resolution controls concurrently adjusts the sample rate and the record length of the acquisition waveform while maintaining the duration constant. A movable and variable length frequency spectrum gate is applied to the digital data samples of the acquired waveform. A window filter is applied to the digital data samples within the gated region a spectrum analysis generator generates frequency domain values over the gates waveform record.

Abstract: A method of realtime human vision system modeling to produce a measure of impairment of a test image signal derived from a reference image signal processes the two signals in respective channels. The signals are converted to luminance image signals and low-pass filtered in two dimensions. The processed image signals are then segmented and block means values are obtained which are subtracted from the pixels in the corresponding processed image signals. Noise is injected into the segmented processed image signals and a variance is calculated for the reference segmented processed image signal and also for the difference between the segmented processed image signals. The variance of difference segmented processed image signal is normalized by the variance for the reference segmented processed image signal, and the Nth root of the result is taken as the measure of visible impairment of the test image signal. The measure of visible impairment may be converted into appropriate units, such as JND, MOS, etc.

Abstract: A rear-mount integrated rotary encoder comprises a mechanical portion and a printed circuit board portion. The mechanical portion of a rear mount integrated rotary encoder comprises a housing including a bushing for receiving one end of a rotatable shaft. The rotatable shaft passes through an open front portion of the housing and is mechanically connected to exposed rotatable circuit contacting members. The printed circuit board portion has an encoder contact pattern formed thereon. The printed circuit board has an area larger than the cross sectional area of the housing. The encoder contact pattern surrounds (or is at least concentric with respect to) an aperture in the circuit board. The rotatable shaft of the rotary encoder is passed through the aperture such that the rotatable circuit contacting members contact the encoder contact pattern on the circuit board.

Abstract: A plasma addressed display or storage device includes a substrate and at least first and second plasma electrodes on an upper surface of the substrate. The first plasma electrode is connected to an external potential and the second plasma electrode is not ohmically connected to an external potential.

Abstract: A measurement receiver demodulator has a first processing channel for producing a filtered signal sample output where the signal samples are processed through a transmission system receiver filter and a second processing channel producing an unfiltered signal sample output where the signal samples are not processed through the transmission system receiver filter. The first processing channel down converts digitally modulated IF signal samples and filters the down converted signal samples using a combined transmission system receiver filter and front end hardware compensation filter. A synchronizer produces timing phase and rate offset parameters that are applied to a resampling filter to synchronize the filtered signal samples to symbol instances of the symbol modulation. The filtered, time-aligned signal samples are scaled using a derived scaling factor. A pilot offset level, if present, is estimated and removed.

Abstract: An improved visual attention model uses a robust adaptive segmentation algorithm to divide a current frame of a video sequence into a plurality of regions based upon both color and luminance, with each region being processed in parallel by a plurality of spatial feature algorithms including color and skin to produce respective spatial importance maps. The current frame and a previous frame are also processed to produce motion vectors for each block of the current frame, the motion vectors being compensated for camera motion, and the compensated motion vectors being converted to produce a temporal importance map. The spatial and temporal importance maps are combined using weighting based upon eye movement studies.

Abstract: A method of determining the blockiness period in DCT-based codecs determines the blockiness period having the maximum measurement value for each image of an input video signal. The blockiness periods having the maximum measurement values for each image are accumulated in a histogram representing the number of images at each different blockiness period. The maximum peak of the histogram represents the blockiness period induced by DCT-based codecs.

Abstract: An optical fiber harness has a unitary plastic body that is formed into a substantially circular member and a straight member. The straight member intersects the circular member forming a chord through the circular member. At least a first attachment member extends from the straight member for securing the optical fiber harness onto a circuit board. Tabs extend outward from the circular member for receiving an optical fiber.

Abstract: A multi-octave, wideband voltage controlled oscillator has a plurality of high impedance current output individual voltage controlled oscillators coupled in parallel to form a bank of voltage controlled oscillators covering at least one high frequency octave. The outputs of the VCOs are wire-OR'd together and the VCOs are selected by a select signal that turns on the desired oscillator(s). A main limiter/divider selects a frequency octave at either the fundamental frequency of the selected VCO or a sub-harmonic thereof as the multi-octave, wideband voltage controlled oscillator output. A reference limiter/divider selects a reference frequency from the selected VCO for use in a phase locked loop. Each VCO has a tank circuit coupled across the bases of a pair of transistors, the emitters of which are coupled through respective current sources to ground. The collectors of the transistors are coupled to the wire-OR'd network.

Abstract: A surface mount probe point socket has a housing with base and a socket extending from the base. The base has a length and width sufficient for attaching the housing to a circuit trace using an electrically conductive material while adding minimal inductance and capacitance to the circuit trace. The socket has a height and diameter for supporting a measurement probe in the housing while adding minimal inductance and capacitance to the measurement probe. A probe point contact is disposed in the bore of the socket for receiving a probe point disposed in the end of the measurement probe to secure the probe in the housing. Two surface mount probe point sockets may be joined together with an alignment gage and attached to adjacent circuit traces to produce a surface mount probe point socket system for differential measurement probes.

Abstract: A method of measuring MPEG PCR jitter, frequency offset and drift rate uses a selectable, constant measurement bandwidth over non-uniform PCR arrival times and a variable PCR rate. The selectable, constant measurement bandwidth is fixed at a frequency that demarcates between jitter and wander. For each received PCR value a PCR interval is determined from the arrival time of the current PCR value and the arrival time of the preceding arrival time. The PCR values, intervals and the fixed bandwidth are input to a set of difference equations, derived either from a hybrid digital-analog PLL model where the frequency offset, drift rate and jitter are extracted from various points in the PLL feedback control system or from a linear filtering approximation to a least mean square (LMS) frequency offset and an LMS drift rate estimator of a simple second order time equation for the PCR values.

Abstract: A removable mechanical attachment system has first and second removable attachment members with each removable attachment member having first and second links. Each link has a base and at least a first extension member extending from one side of the base. The links are secured to respective surfaces of first and second electrical sections with at least one of the extension members of the first and second links of each of the first and second removable attachment members extending past open end faces of the first and second electrical sections. The electrical sections are positioned in a proximate abutting relationship at the open end faces with the extension members extending past the open end faces of the electrical sections overlapping the other extension members of the first and second removable attachment members. A bonding material is applied to the overlapping extension members to join the extension members together.

Abstract: An integrated circuit includes a termination for a transmission line having a predetermined characteristic impedance. The termination includes a controllable impedance circuit, including a multiplier, coupled to the transmission line. A reference impedance, placed external to the integrated circuit, has an impedance related to the characteristic impedance of the transmission line.

Abstract: A telecom mask testing zoom function draws mask. pixels into a raster memory. In this way, the mask is treated as a waveform. Comparison of the mask pixels and waveform pixels to detect collision between a waveform pixel and a mask pixel (i.e., a mask violation) is performed substantially in real time, as the pixels are being composited into the raster memory by the rasterizer. The mask is scalable and repositionable by the rasterizer under control of a controller, because it is treated as a waveform. The mask is lockable to the waveform because both are stored in pixel form in raster memory by the rasterizer under control of the controller.

Abstract: A method of zooming in/out for a graphics image on a display screen encompasses drawing a rectangle on the display screen, either entirely within a display area of the display screen for two-dimensional zoom in/out or along one axis within a peripheral area of the display screen for one-dimensional zoom in/out. Once the rectangle is drawn by dragging from one corner to an opposite corner, tapping or clicking within the rectangle causes a zoom in action and tapping or clicking outside the rectangle causes a zoom out action.