Abstract: A measuring apparatus is provided for electrical signals. The measuring apparatus includes an analog-to-digital (A/D) converter configured to A/D-convert an analog signal to be measured, and an integrator configured to perform integration time processing for a plurality of digital values output from the A/D converter based on an integration time. The integrator is configured to output a plurality of measured values obtained by the integration time processing. A noise level calculation unit is configured to calculate a noise level of the analog signal to be measured from the plurality of measured values obtained by the integration time processing, and a display unit is configured to display noise levels corresponding to a plurality of integration times.

Abstract: A measurement system is provided that performs a qualified store algorithm. When performing the algorithm, the measurement system stores in memory digital data samples acquired during a time window while a qualification signal is valid, a preselected number of digital data samples acquired prior to and adjacent in time to the time window, and a preselected number of digital data samples acquired subsequent to and adjacent in time to the time window.

Abstract: An active probe adapter adapts an active probe to a PXI instrumentation module. The active probe adapter includes a first module interface (MI) connector on a first side of the active probe adapter. The first MI connector is configured to connect to a corresponding interface connector of the PXI instrumentation module. The active probe adapter further includes a plurality of probe pads on a second side of the active probe adapter opposite to the first side. The plurality of probe pads is configured to interface with an active probe employed with the PXI instrumentation module. The active probe adapter may include a second MI connector on the active probe first side configured to connect to a PXI power module and provide power to the active probe.

Abstract: A method for operating a data processing system to detect the presence of an event in a data stream includes an ordered sequence of digital values, xi, for i=1 to Nd is disclosed. The method includes causing the data processing system to determine a base value for a statistical parameter of the data digital values within a training window. Then for each xi in a region of interest in the ordered sequence of digital values, the data processing system determines a sliding value for the statistical parameter corresponding to that xi by measuring the statistical parameter of the xi within a sliding window containing the xi and which is different for each xi. The data processing system compares the sliding value to the base value for each xi in the region of interest to determine if the xi is part of an event.

Abstract: A system for testing advanced antennas includes an antenna unit controller, a radio frequency instrument, and a test controller. The antenna unit controller is configured to connect to a device that includes an advanced antenna under test in an anechoic chamber. The radio frequency instrument is connected to a probe antenna in the anechoic chamber. The test controller is configured to control the test of the advanced antenna by controlling the antenna unit controller to reconfigure the advanced antenna under test, and by controlling the radio frequency instrument to communicate wirelessly with the device via the probe antenna in each of a sequence of multiple configurations of the advanced antenna while the advanced antenna remains in the anechoic chamber.

Abstract: An impedance measurement method is provided having a certain level of measurement sensitivity across all ranges of impedance and capable of covering a wide measurement range. In the method, a device under test (DUT) is connected in series or in parallel to a signal line, a measurement signal is transmitted from a signal source, an input signal a1 into the DUT, a reflected signal reflected from the DUT, and a passed signal that passed through the DUT are measured, S-parameters S11 and S21 are calculated based on respective measured values of the input signal, the reflected signal, and the passed signal, and an impedance Zx of the DUT is calculated based on a formula: Zx=2Z0S11/S21, where Z0 is a characteristic impedance.

Abstract: A system and method are provided that reduce the amount of time required to perform transient circuit and envelope transient circuit simulations. The total simulation time is partitioned into n simulation segments of equal lengths of time and adjacent simulation segments are overlapped in time by a predetermined overlap time period, Tov. The simulation segments are then simulated in parallel and the simulation results are merged into a final simulation waveform. The predetermined overlap time period Tov is determined using a non-iterative process that can be performed very quickly. Consequently, the overall amount of time that is required to perform the simulation is greatly reduced.

Abstract: A measurement instrument and associated method: receive at a first input an aggressor signal (e.g., a supply voltage) from a device under test (DUT); capture samples of the aggressor signal; receive at a second input a victim signal from the DUT, wherein the received victim signal includes jitter induced thereon from the aggressor signal; capture samples of the received victim signal; apply the captured samples of the aggressor signal and the captured samples of the received victim signal to a predetermined model, which represents the jitter induced onto the received victim signal from the aggressor signal, to produce a system of equations; ascertain a plurality of unknown parameters in the predetermined model from the system of equations; and apply the predetermined model with the ascertained parameters to the captured samples of the aggressor signal to estimate the jitter induced onto the received victim signal from the aggressor signal.

Abstract: An oscilloscope includes at least one demonstration signal generator integrated as part of the oscilloscope. The demonstration signal generator generates stimulus signals that consist of digital samples of various different stored waveforms without the need of a separate demonstration board or signal source. The demonstration signal generator may loop through different sections of the stored waveforms to generate respective stimulus signals that include sequences of digital samples from the different waveforms in combination, to provide a broad range of stimulus signals. The stimulus signals may be displayed on the oscilloscope or output from the oscilloscope as demonstration mode stimulus signals to demonstrate the capabilities of the oscilloscope to customers or for training.

Abstract: Provided are a measurement apparatus and a measurement method capable of measuring inter-terminal capacitances of a three-terminal device while reproducibility is high and influences of residual inductances are cancelled. The measurement apparatus includes: a route selector including a first terminal, a second terminal, a third terminal, a fourth terminal, a fifth terminal, and a sixth terminal, the fourth to sixth terminals being configured to connect to any of the first to third terminals; an LCR meter; a device under test, which is a three-terminal device; first, second, and third cables for respectively connecting the fourth to sixth terminals of the first route selector and first, second, and third terminals of the device under test to each other; and fourth, fifth, and sixth cables for respectively connecting the first to third terminals of the first route selector and first, second, and third terminals of the LCR meter to each other.

Abstract: A system and method compensates distortions in transmission line measurement by obtaining a frequency response of a transmission line responsive to a test signal; approximating the frequency response as a function of a complex valued variable; and applying an analytic continuation to extend the function of the complex valued variable to a modified frequency response corresponding to a lossless frequency response, to compensate for loss in the transmission line. The modified frequency response may be further sampled at linearly spaced points in a wave number domain to compensate for dispersion of the transmission line.

Abstract: A method of operating a data processing system to operate a first instrument and a second instrument connected to the data processing system is disclosed. The method includes displaying a measurement table. The data processing system receives user input defining a first parameter that is to be varied during a testing procedure by the first instrument and a first measurement to be made by the second instrument during the test procedure, a plurality of first parameter values to be used in the testing procedure. The data processing system causes the first instrument to provide each of the first parameter values and the second instrument to make the measurement and enter the measurement in a corresponding cell of a second row in the measurement table when the first instrument provides each of the first parameter values.

Abstract: A method for testing an air interface device by simulating multi-UE uplink virtual MIMO includes receiving, by a multi-UE simulator, a downlink signal transmission from an air interface device under test. The method further includes decoding, by the multi-UE simulator, the downlink signal transmission to identify simulated UEs with uplink resource block grants. The method further includes assigning, by the multi-UE simulator, uplink data transmissions for the simulated UEs with uplink resource block grants to antennas or cables such that uplink data transmissions for simulated UEs with overlapping uplink resource block grants are assigned to different antennas or cables. The method further includes testing, by the multi-UE simulator, uplink virtual MIMO processing capability of the air interface device under test by generating and transmitting uplink signals from the simulated UEs with the overlapping uplink resource block grants to the air interface device under test using the different antennas or cables.

Abstract: A test system for testing a device under test includes: a signal processor configured to generate a plurality of independent signals and to apply first fading channel characteristics to each of the independent signals to generate a plurality of first faded test signals; a test system interface configured to provide the plurality of first faded test signals to one or more signal input interfaces of the device under test (DUT); a second signal processor configured to apply second fading channel characteristics to a plurality of output signals of the DUT to generate a plurality of second faded test signals, wherein the second fading channel characteristics are derived from the first fading channel characteristics; and one or more test instruments configured to measure at least one performance characteristic of the DUT from the plurality of second faded test signals.

Abstract: A method for operating a data processing system to identify documents in a library includes a plurality of documents and a plurality of concepts exemplified by the plurality of documents and computer readable media that stores instructions for causing a data processing system to execute that method are disclosed. The method includes causing the data processing system to identify candidate documents matching a user provided search keyword from the library, causing the data processing system to generate a topical graph relating concepts contained in the candidate documents to one another, and clustering the candidate documents based on the topical graph. For each cluster, the data processing system displays a summary of the candidate documents in that cluster together with a cluster name that characterizes that cluster.

Abstract: In an exemplary embodiment of the disclosure, a signal analyzer includes at least one noise reduction system in the form of an adaptive noise reduction system. The adaptive noise reduction system executes an adaptive noise floor extension (NFE) procedure that includes determining a predicted standard deviation of a response by the signal analyzer to intrinsic noise in the signal analyzer when various signal processing parameters desired by a user are applied to an input signal. The predicted standard deviation is then used in the signal analyzer to select and apply various noise subtraction values upon the input signal before displaying of a signal spectrum of the input signal upon a display of the signal analyzer. The adaptive NFE procedure is directed at reducing or eliminating various ambiguities and/or errors in the displayed signal spectrum.

Abstract: A method is provided for calibrating a multiport measurement system having a local oscillator and a respective receiver associated with each port. The method includes performing a relative calibration by vector calibrating ports of the multiport measurement system and generating relative error-correction terms for the ports. Further, the method includes performing an absolute calibration by calibrating an amplitude response of the receivers of the multiport measurement system, and removing a local oscillator unknown phase response using a single phase reference coupled to a vector calibrated port and transferring cross-frequency phase correction terms from this vector calibrated port to the receivers of the other vector calibrated ports.

Abstract: Various illustrative embodiments pertain to a signal quality evaluation system having a decision feedback equalizer (DFE) and a signal quality evaluator. The DFE receives an input signal containing symbols that represent digital data and uses the symbols to generate multiple detection thresholds. Each detection threshold is one of several detection thresholds that can be generated by the DFE by processing one or more symbols present in the input signal prior to a current clock cycle of a clock that is recovered from the input signal. The signal quality evaluator uses the detection thresholds provided by the DFE to detect transitions in the input signal. The signal quality evaluator may execute jitter measurements and/or time interval error (TIE) measurements by evaluating the transitions in the input signal.

Abstract: A method for controlling a screen in a data processing system to generate displays that include portions of an underlying scene is disclosed. The method includes displaying on the screen a first displayed scene, detecting a long touch gesture, and displaying a second scene on the screen. The first displayed scene is characterized by a first magnification and a first offset relative to the underlying scene. The second displayed scene includes a different portion of the underlying scene and is characterized by a second magnification that is different from the first magnification. In one aspect of the invention, the second displayed scene is characterized by a second offset that is determined by the long touch gesture, and the second offset depends on the first displayed scene and the long touch gesture.

Abstract: Radio frequency (RF) receivers and methods to spread spectral energy of spurious responses of mixers over a frequency band are disclosed. For example, a receiver includes first and second mixers, and first and second variable frequency oscillators (VFOs). The first mixer is configured to receive an RF signal and provide an intermediate frequency (IF) signal. The second mixer is coupled with the first mixer and configured to receive the IF signal and provide a baseband signal. The first VFO is coupled with the first mixer and configured to provide a first angle modulated LO signal. The second VFO is coupled with the second mixer and configured to provide a second angle modulated LO signal. The first and second mixers provide a stable frequency downconversion.