公开(公告)号：US20230050303A1

公开(公告)日：2023-02-16

申请号：US17877829

申请日：2022-07-29

Applicant: Tektronix, Inc.

Inventor： John J. Pickerd ,  Kan Tan

IPC: G06F11/27 ,  G06F11/22 ,  G06F1/02

Abstract: A test and measurement system has a test and measurement instrument, a test automation platform, and one or more processors, the one or more processors configured to execute code that causes the one or more processors to receive a waveform created by operation of a device under test, generate one or more tensor arrays, apply machine learning to a first tensor array of the one or more tensor arrays to produce equalizer tap values, apply machine learning to a second tensor array of the one of the one or more tensor arrays to produce predicted tuning parameters for the device under test, use the equalizer tap values to produce a Transmitter and Dispersion Eye Closure Quaternary (TDECQ) value, and provide the TDECQ value and the predicted tuning parameters to the test automation platform. A method of testing devices under test includes receiving a waveform created by operation of a device under test, generating one or more tensor arrays, applying machine learning to a first tensor array of the one or more tensor arrays to produce equalizer tap values, applying machine learning to a second tensor array of the one or more tensor arrays to produce predicted tuning parameters for the device under test, using the equalizer tap values to produce a Transmitter Dispersion Eye Closure Quaternary (TDECQ) value, and providing the TDECQ value and the predicted tuning parameters to a test automation platform.

公开(公告)号：US20220373597A1

公开(公告)日：2022-11-24

申请号：US17745797

申请日：2022-05-16

Applicant: Tektronix, Inc.

Inventor： Maria Agoston ,  John J. Pickerd ,  Kan Tan

IPC: G01R31/319 ,  H04B17/00 ,  G01R31/26 ,  H04L1/20

Abstract: A test and measurement system includes a machine learning system, a test and measurement device including a port configured to connect the test and measurement device to a device under test (DUT), and one or more processors, configured to execute code that causes the one or more processors to: acquire a waveform from the device under test (DUT),transform the waveform into a composite waveform image, and send the composite waveform image to the machine learning system to obtain a bit error ratio (BER) value for the DUT. A method of determining a bit error ratio for a device under test (DUT), includes acquiring one or more waveforms from the DUT, transforming the one or more waveforms into a composite waveform image, and sending the composite waveform image to a machine learning system to obtain a bit error ratio (BER) value for the DUT.

公开(公告)号：US10904042B2

公开(公告)日：2021-01-26

申请号：US16116677

申请日：2018-08-29

Applicant: Tektronix, Inc.

Inventor： John J. Pickerd ,  Kan Tan ,  Pirooz Hojabri

IPC: H03H7/46 ,  H04B17/30 ,  H04L25/03

Abstract: A continuously or step variable passive noise filter for removing noise from a signal received from a DUT added by a test and measurement instrument channel. The noise filter may include, for example, a splitter splits a signal into at least a first split signal and a second split signal. A first path receives the first split signal and includes a variable attenuator and/or a variable delay line which may be set based on the channel response of the DUT which is connected. The variable attenuator and/or the variable delay line may be continuously or stepped variable, as will be discussed in more detail below. A second path is also included to receive the second split signal and a combiner combines a signal from the first path and a signal from the second path into a combined signal.

公开(公告)号：US10476704B2

公开(公告)日：2019-11-12

申请号：US16125684

申请日：2018-09-08

Applicant: Tektronix, Inc.

Inventor： Kan Tan

IPC: H04L25/03 ,  G01R13/02 ,  G01R31/317

Abstract: Disclosed is a mechanism for limiting Intersymbol Interference (ISI) when measuring uncorrelated jitter in a test and measurement system. A waveform is obtained that describes a signal. Such waveform may be obtained from memory. A processor then extracts a signal impulse response from the waveform. The processor selects a window function based on a shape of the signal impulse response. Further, the processor applies the window function to the signal impulse response to remove ISI outside a window of the window function while measuring waveform jitter. The window function may be applied by applying the window function to the signal impulse response to obtain a target impulse response. A linear equalizer is then generated that results in the target impulse response when convolved with the signal impulse response. The linear equalizer is then applied to the waveform to limit ISI for jitter measurement.

公开(公告)号：US20190068411A1

公开(公告)日：2019-02-28

申请号：US16125684

申请日：2018-09-08

Applicant: Tektronix, Inc.

Inventor： Kan Tan

IPC: H04L25/03

Abstract: Disclosed is a mechanism for limiting Intersymbol Interference (ISI) when measuring uncorrelated jitter in a test and measurement system. A waveform is obtained that describes a signal. Such waveform may be obtained from memory. A processor then extracts a signal impulse response from the waveform. The processor selects a window function based on a shape of the signal impulse response. Further, the processor applies the window function to the signal impulse response to remove ISI outside a window of the window function while measuring waveform jitter. The window function may be applied by applying the window function to the signal impulse response to obtain a target impulse response. A linear equalizer is then generated that results in the target impulse response when convolved with the signal impulse response. The linear equalizer is then applied to the waveform to limit ISI for jitter measurement.

公开(公告)号：US10209276B2

公开(公告)日：2019-02-19

申请号：US15282593

申请日：2016-09-30

Applicant: TEKTRONIX, INC.

Inventor： Kan Tan

IPC: G01R13/02 ,  H04L25/03 ,  H04L12/26 ,  H04B3/462

Abstract: A method of employing a Decision Feedback Equalizer (DFE) in a test and measurement system. The method includes obtaining an input signal data associated with an input signal suffering from inter-symbol interference (ISI). A bit sequence encoded in the input signal data is determined to support assigning portions of the input signal data into sets based on the corresponding bit sequences. The DFE is applied to each set by employing a DFE slicer pattern corresponding to each set, which results in obtaining a DFE adjusted waveform histogram/PDF/waveform database graph for each set adjusted for ISI and accurately captures jitter suppression. The DFE adjusted waveform histogram/PDF/waveform database graphs are normalized and combined into a final histogram/PDF/waveform database graph for determining an eye contour of an eye diagram and jitter measurements.

公开(公告)号：US10145874B2

公开(公告)日：2018-12-04

申请号：US14673747

申请日：2015-03-30

Applicant: Tektronix, Inc.

Inventor： Kan Tan ,  John J. Pickerd

IPC: G01R27/28 ,  G01R27/06 ,  G01R21/133 ,  G01R23/00 ,  G01R23/02 ,  G01R31/28 ,  G01R27/16

Abstract: A method for determining scattering parameters of a device under test using a real-time oscilloscope. The method includes calculating a reflection coefficient of each port of a device under test with N ports, wherein N is greater than one, based on a first voltage measured by the real-time oscilloscope when a signal is generated from a signal generator. The method also includes determining an insertion loss coefficient of each port of the device under test, including calculating the insertion loss coefficient of the port of the device under test to be measured based on a second voltage measured by the real-time oscilloscope when a signal is generated from a signal generator.

公开(公告)号：US09933458B2

公开(公告)日：2018-04-03

申请号：US14674344

申请日：2015-03-31

Applicant: Tektronix, Inc.

Inventor： John J. Pickerd ,  Kan Tan

IPC: G05B11/32 ,  G01R13/02 ,  H03M1/10 ,  G01R13/22 ,  H03M1/12

CPC classification number: G01R13/0218 ,  G01R13/0272 ,  G01R13/225 ,  H03M1/1052 ,  H03M1/1215

Abstract: A test and measurement instrument including a splitter configured to split an input signal into at least two split signals, at least two harmonic mixers configured to mix an associated split signal with an associated harmonic signal to generate an associated mixed signal, at least two digitizers configured to digitize the associated mixed signal, at least two MIMO polyphase filter arrays configured to filter the associated digitized mixed signal of an associated digitizer of the at least two digitizers, at least two pairs of band separation filters configured to receive the associated digitized mixed signals from each of the MIMO polyphase filter arrays and output a low band of the input signal and a high band of the input signal based on a time different between the at least two digitizers and a phase drift of a local oscillator, and a combiner configured to combine the low band of the input signal and the high band of the input signal to form a reconstructed input signal.

公开(公告)号：US20170168092A1

公开(公告)日：2017-06-15

申请号：US15143429

申请日：2016-04-29

Applicant: Tektronix, Inc.

Inventor： Kan Tan ,  John J. Pickerd

IPC: G01R13/02 ,  G01R23/175

CPC classification number: G01R13/029 ,  G01R13/0218 ,  G01R19/2509 ,  G01R23/175 ,  G01R31/31709

Abstract: Embodiments of the present invention provide techniques and methods for improving signal-to-noise ratio (SNR) when averaging two or more data signals by finding a group delay between the signals and using it to calculate an averaged result. In one embodiment, a direct average of the signals is computed and phases are found for the direct average and each of the data signals. Phase differences are found between each signal and the direct average. The phase differences are then used to compensate the signals. Averaging the compensated signals provides a more accurate result than conventional averaging techniques. The disclosed techniques can be used for improving instrument accuracy while minimizing effects such as higher-frequency attenuation. For example, in one embodiment, the disclosed techniques may enable a real-time oscilloscope to take more accurate S parameter measurements.

公开(公告)号：US20170089954A1

公开(公告)日：2017-03-30

申请号：US14870357

申请日：2015-09-30

Applicant: Tektronix, Inc.

Inventor： John J. Pickerd ,  Kan Tan

IPC: G01R13/02

CPC classification number: G01R13/0218 ,  G01R13/0272 ,  G01R13/029 ,  H03M1/188

Abstract: A test and measurement instrument, including a splitter configured to split an input signal into two split input signals and output each split input signal onto a separate path and a combiner configured to receive and combine an output of each path to reconstruct the input signal. Each path includes an amplifier configured to receive the split input signal and to compress the split input signal with a sigmoid function, a digitizer configured to digitize an output of the amplifier; and at least one processor configured to apply an inverse sigmoid function on the output of the digitizer.