Tektronix, Inc.

Textronix, Inc.

Benjamin A Ward

Kan Tan

John J Pickerd

Kenneth P Dobyns

Gary J Waldo

Mark L Guenther

Michael C Seckora

T Naveen

Embodiments of this invention include a test and measurement instrument and associated methods for acquiring and stitching wide overlapped non-uniform frequency bands so that a user specified band can be efficiently displayed and analyzed. The test and measurement instrument includes a user interface to receive the user specified frequency span. Acquisition circuitry acquires one or more predefined frequency bands having non-uniform overlapping frequency ranges. A frequency band processing section can decimate the acquired frequency bands, mask the acquired frequency bands, and stitch the masked frequency bands together. A display section displays the user specified frequency span using the stitched frequency bands. Due to the overlap configuration of the wide non-uniform bands, any user specified span between 50 kHz and 6 GHz, or thereabout, can be covered by two bands.

Minimal reconfiguration spectrum stitching with overlapped bands

Disclosed is a test and measurement instrument that includes a signal input structured to receive a modulated radio frequency (RF) signal under test and a demodulator structured to extract a digital signal from the received modulated RF signal. The extracted digital signal has a measurable parameter. The instrument also includes a display controller structured to display the extracted demodulated signal at one of at least two different intensities based on the measured parameter of the digital signal. In other embodiments the signal need not be an RF signal. Methods of operation are also described.

Selective display of waveforms governed by measured parameters

A test and measurement instrument acquires a signal from a device under test, displays that signal as a source waveform, and makes measurements on that source waveform with regard to a predetermined property or event. The test and measurement instrument employs the method of the subject invention for placing these measurements into a waveform and directly correlating a position in the measurement waveform to the same area on the source waveform where they were measured. Specifically, the subject invention displays the correlation of points on a source waveform and a measurement waveform without requiring the use of a common horizontal time scale. In one embodiment of the invention, the measurement waveform is a histogram and a pointer to a given location in the histogram causes identification of corresponding areas in the source waveform.

Method and apparatus for visually time-correlating waveform measurements to a source waveform

A jitter separation apparatus and method, based on spectrum analysis, separates deterministic jitter and random jitter using their spectral properties. Deterministic jitter is periodic and nature and exhibits a spectrum of impulses, whereas random jitter exhibits a broad, flat spectrum. A time domain histogram and a frequency domain histogram of the signal are investigated to obtain jitter components.

Apparatus and method for spectrum analysis-based serial data jitter measurement

A test and measurement apparatus and method wherein a software implemented phase lock loop recovers a clock signal associated with the received data signal, the recovered clock signal being used to do TIE measurement, to generate eye diagram and to do mask testing.

Signal acquisition method and apparatus using integrated phase locked loop

A time stamping method for threshold crossing points of an input signal uses a dithered threshold level. Digital data samples are acquired for the input signal and time marks are determined for the threshold crossings using interpolation. The time marks are stores as the time stamps. A threshold offset value generator generates a distribution of offset values for dithering the threshold value. Time interval values are generated from the time stamps and the number of occurrences of time interval values are accumulated in time bins. A time interval distribution histogram and statistical time interval distribution data, such as the mean, standard deviation and minimum and maximum time intervals may be generated.

Method of waveform time stamping for minimizing digitization artifacts in time interval distribution measurements

The time stamping method for an input signal generates time marked digital data values as a reference edge and defines at least a first time stamp in the reference edge. Digital data samples of the input signal are acquired to create a waveform record of the input signal. The digital data samples of a waveform record edge are compared to time equivalent digital data values of the reference edge to generate a error value representative of the difference between the waveform record edge and the reference edge. A time offset value is generated from the error value to vary the time location of the reference edge and the comparison and time offset generating steps are repeated to minimize the error value. The time offset value at the minimum error value is combined with a time location of nearest digital data sample of the waveform record edge to generate a waveform record edge time stamp.

Method of time stamping a waveform edge of an input signal

A variable coefficient, non-separable spatio-temporal interpolation filter is used to deinterlace an interlaced video signal to produce a progressive video signal. The interlaced video signal is input to a video memory which in turn provides a reference and plurality of offset video signals representing the pixel being interpolated and spatially and temporally neighboring pixels. A coefficient index, transmitted with the interlaced video as an auxiliary signal, or derived from motion vectors transmitted with the interlaced video, or derived directly from the interlaced video signal, is applied to a coefficient memory to select a set of filter coefficients. The reference and offset video signals are weighted together with the filter coefficients in the spatio-temporal interpolation filter, such as a FIR filter, to produce an interpolated video signal. The interpolated video signal is interleaved with the reference video signal, suitably delayed to compensate for filter processing time, to produce the progressive video signal.

Deinterlacing of video using a variable coefficient spatio-temporal

A sequence of events detector provides a way to continuously monitor serial digital data and precisely define the behavior that it must exhibit in order to qualify as the sequence of events that the user wishes to detect. A plurality of evaluation windows each sequentially examine the behavior of one or more signals, comparing this behavior with predefined criteria. Each evaluation window is activated to begin its portion of the overall evaluation process by a match signal from the preceding window, indicating that its predefined criteria were met. In one version, a sequence starting circuit activates the first evaluation window in response to an external signal or the occurrence of a predefined condition, and a multiplexer trigger source circuit selects as the overall detector output the match signal output of the last evaluation window used to define the overall sequence of events. In another version, each evaluation window explicitly reports a failure if its predefined criteria are not met.

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Portland, OR, United States of America

Benjamin A Ward