Abstract: A method of frequency response measurement for a sinusoidal test signal, such as a swept sinusoid signal, a multi-burst sinusoidal signal or the like, uses a complex sinusoid window at a particular frequency for correlation with the sinusoidal test signal. The resulting complex correlation magnitude signal is thresholded as a function of a percentage of a maximum complex correlation magnitude. A centroid of the thresholded complex correlation magnitude signal is found, and the complex correlation magnitude at the centroid is the frequency response at the particular frequency.

Abstract: A system includes a plurality of digital storage oscilloscopes (DSOs) in which each DSO requires a respective temporal portion of a signal under test (SUT) according to a synchronized triggering signal and respective post-trigger count periods such that a plurality of acquisition records may be concatenated to produce a longer acquisition record.

Abstract: A streaming media quality analyzer system compares original streaming media from a source, or original packetized streaming media from the source, with a reconstructed packetized streaming media representing the packetized streaming media as received over a network in a connectionless manner at a remote site. At the remote site the received packetized streaming media is analyzed to determine time of arrival of the packets including identification of missing packets. The analysis results are transmitted over the network to a measurement site and used to reconstruct the received packetized streaming media from the original packetized streaming media. The reconstructed packetized streaming media is then analyzed to determine the quality of the packetized streaming media received at the remote site.

Abstract: A attachable/detachable probing tip system (10) has a housing (12) that includes a probing tip mounting member (14) and opposing substantially orthogonal attachment (16, 18) arms extending from the probing tip mounting member. The attachment arms define an inner surface of the probing tip mounting member in which is disposed at least a first a non-compressive set, resilient member (56). First and second probing tips (42, 44) are disposed over the non-compressive, resilient member (56) and secured to the housing by latching means (60, 66, 92, 96, 100, 130). The attachable/detachable probing tip system allows mounting of the probing tips (42, 44) to probing contacts on a device under test without a probe body or probing tip member (38) being attached. The attachment arms (16, 18) allows a probe body or probing tip member (38) to be attached and detached to the probing tip system (10). The probing tip member (38) includes contact pins that engage contact areas (82, 82, 92) of the probing tips (42, 44).

Abstract: A signal acquisition probing system uses a micro-cavity laser to acquire an electrical signal from a device under test. The micro-cavity laser has VCSEL gain mediums and an electro-optic optical resonant cavity. The micro-cavity laser is pumped by an external laser source and generates polarized frequency modulated optical signals derived from the device under test electrical signal creating an electro-magnetic field distribution in electro-optic material in the micro-cavity laser that overlaps the optical path of the polarized optical signals propagating in the electro-optic material. The polarized frequency modulated optical signals are coupled to an optical receiver which converts the polarized frequency modulated optical signals to an electrical signal. The electrical signal is coupled to measurement test instrument for processing and displaying of the electrical signal.

Abstract: A heat sink hand placement tool for manually installing a heat sink to an integrated circuit (IC). The heat sink tool includes a heat sink interface block having a lower surface adapted to provide a force on a heat sink disposed over an IC. A force transducer interfaces with an upper surface of the heat sink interface block to produce an electrical signal, which is routed to a measurement circuit to measure the electrical signal. A chassis is disposed over the force transducer and the measurement circuit, wherein the chassis is adapted to receive a force from a user, such that the force is transmitted to the lower surface of the heat sink interface block. The measurement circuit then provides an indication of the force being applied within a predetermined range.

Abstract: Audio processing using a video rasterizer allows simultaneous display of both audio and video data on the same raster display. Audio samples are clocked into a buffer memory, such as a first-in, first-out (FIFO) buffer, by an audio clock and clocked out of the buffer memory by a rasterizer (system) clock to allow the audio data to cross over from the audio clock domain to the video clock domain. The audio data is then upsampled by a sample ratio converter/interpolator before being processed by a video display engine. The video display engine includes a polyphase filter for upsampling display data for input to a rasterizer from which the data is read for display.

Abstract: A jitter measurement method using a down-mixing or down-converting topology in a jitter measurement system preserves the jitter UI rather than the jitter seconds. An input serial data stream at a high baud is mixed with a stable local oscillator frequency that is close to that of the high baud. The difference between the high baud and the local oscillator frequency is passed by a filter as a lower rate serial stream. A clock recovery circuit recovers a lower rate clock from the lower rate serial stream, or an amplitude modulation removal stage converts the lower rate serial stream to a lower rate NRZ signal, or the lower rate serial signal is digitized. Jitter measurement is performed by a jitter measurement stage on the lower rate clock, the lower rate NRZ signal, or the digitized lower rate serial signal.

Abstract: A high isolation RF switch for launching a selected one of two RF signals into a slabline transmission line structure has a three switch configuration—a pair of input switches coupled to corresponding input ports and a transition switch coupled to an output port via a slabline transmission line. The input switches select one of the input ports for coupling to the transition switch, and the transition switch couples the selected input port from the input switches to the output port. A grounded conductor is situated between the input ports in a cavity of a housing within which the high isolation RF switch is located to provide isolation between the input ports. Additional isolation between the input ports is provided by coupling the non-selected RF signal to ground, either by grounding the non-selected input to the transition switch or the non-selected input port.

Abstract: A hand-held probing adapter secures a measurement probing system having a probe body coupled to a probing tip member via at least a first coaxial cable. The adapter has a housing with an interior cavity exposed at opening in opposing ends of the housing. The housing has a first portion at one end of the interior cavity for receiving the probe body and a second portion at the other end of the cavity for receiving the probing tip member. The first portion of the housing has means for securing the probe body in the housing, such as rib and slot combination. The second portion also has means for securing the probe tip member in the housing, such as with a pin in the interior cavity of the housing engaging a slot in the probe tip member. A portion of the probe tip member is exposed at one of the openings in the housing. Compliant members disposed in the second portion of the interior cavity providing axial and lateral rotation movement of the probing tip member.

Abstract: A method of generating reports for data in the form of a multiplicity of data files in an accessible data storage medium uses a user interface to specify a desired report and a sample data file name, the data file names having a variable portion and a non-variable portion. A search algorithm searches the accessible data storage medium for all related data files having the same non-variable portion in their data file names, and logically groups the data files according to the variable portion of their data file names. The related data files are processed according to specified parameters, such as thresholds and limits, and a display is provided of the analysis results, highlighting significant data. The report results with linked data may be stored on an intranet site in an appropriate format to be accessible via a web page using a conventional web browser.

Abstract: A high-speed digital-to-analog converter (DAC) measurement method acquires and quantizes an analog ramp output by the DAC corresponding to a digital ramp input to produce a quantized ramp, determines a start and end of the quantized ramp, obtains a difference between the quantized ramp and an ideal ramp to produce a quantized periodic signal (triangular or sinusoidal), determines a frequency for a qualified peak from an FFT of the quantized periodic signal, produces a mask filtered periodic signal from an iFFT around the qualified peak, and determines a sample window spanning a local maximum and minimum for each period of the quantized periodic signal. The ramp step levels are the averages of the samples within each sample window. From the step levels in DAC LSB's, resolution, monotonicity, differential lineary and integral linearity are determined for the DAC.

Abstract: A low phase noise YIG oscillator based phase locked loop couples an output frequency to a delay line discriminator to provide a phase noise feedback signal to a wideband tuning port of the YIG oscillator. A delay line in the delay line oscillator may be implemented with either a resonant circuit or a bandpass filter of sufficient bandwidth so that the output frequency and phase noise sidebands are not attenuated. The resonant circuit may be implemented as a YIG sphere integrated into the YIG oscillator in the same magnetic path as the YIG sphere in the oscillator circuitry.

Abstract: A method and apparatus for representing a complex vector signal by determining representative coordinates for the complex vector signal, wherein at least some of the determined representative coordinates are associated with corresponding reference coordinates; associating each of at least a portion of the determined representative coordinates and corresponding reference coordinates with at least one of a plurality of temporal spans; and selectively processing each of a plurality of temporal spans.

Abstract: A method for reducing drift in a step stimulus from a sampling system, such as an oscilloscope, is described having an initial step of setting a calibration repetition rate. A step stimulus stabilization calibration is performed to acquire a reference mid-crossing time and the current mid-crossing time. Acquisition cycles of TDR/TDT waveform samples are acquired equal to the repetition rate with the initial strobe delay interval in the sampling system being adjusted by the difference between the reference mid-crossing time and the current mid-crossing time. The step stimulus stabilization calibration is performed again to acquire a new current mid-crossing time and initial strobe delay interval and more acquisition cycles of TDR waveform samples are acquired equal to the repetition rate. The process continues until a stop command is activated for the sampling system.

Abstract: An inverted strain relief for receiving a coaxial cable has a housing with a bore therethrough defining first and second apertures in opposing surfaces of the housing. The bore surface is defined by at least a first radius scribing an arc from the perimeter of the first aperture to the second aperture. A smaller second radius scribes an arc tangential to the arc of the first radius over a portion of the exterior surface of the housing. Alternately, the first and second radii may define the surface of the bore with the second radius extending over a portion of the exterior surface of the housing. The bore in the housing is definable by an additional aperture formed adjacent to the first aperture. The surface of the bore is defined by at least the first radius extending from the perimeters of the adjacent apertures.

Abstract: Apparatus in accordance with the subject invention maintains an exponentially decayed histogram of the counts of new pixels for each active channel, together with a running count of time and number of acquisitions. At regular intervals determined by a maximum time or by a minimum number of acquisitions it computes a new threshold for each active channel. This threshold will theoretically produce “N” nominally unusual waveforms per second where N is defined by a user “sensitivity” control. The raw histogram is smoothed to provide a stable “tail” of small probabilities. Once a threshold has been determined, subsequent waveforms with more than this number of new pixels are re-examined to determine the number of “really new” pixels. “Really new” pixels are defined as those that are not adjacent to pixels remaining from earlier acquisitions. Only those waveforms that have more “really new” pixels than a specified fraction of the basic threshold are reported as anomalies.

Abstract: A surround sound display has a graphic sound stage image, including speakers representing sources and a central listener, and bent correlation meter scales for each stereo channel. The correlation meter scales have values from +1 at one end to ?1 at the other end and are bent to start from a central point along one side of the display between the speakers representing the stereo channels to a point along the opposing adjacent sides of the display outside the respective speakers. A marker, either in the form of individual pointers for each scale or as a fill area that spans the scales, indicates the correlation between the stereo channels. The thickness of the fill area indicates the amplitudes of the stereo channels.

Abstract: A two-dimensional video timing display with numeric readouts allows a user to quickly, easily and precisely measure the timing difference between video signals. A graphic display area within a raster display region provides a two-dimensional display of vertical timing offset and horizontal timing offset of an input video signal with respect to a reference video signal, the graphic display area including a reference indicator centered in the graphic area indicating the timing of the reference video signal and a timing indicator in the graphic area indicating the timing of the input video signal with respect to the reference video signal. A numeric display area is adjacent the graphic display area to display the actual vertical and horizontal timing offsets in appropriate units according to the format of the input video signal with a precision to one video clock cycle.