Abstract: A multiple-input multiple-output (MIMO) over-the-air (OTA) test system and method are provided that enable a device under test (DUT) to be tested that has no antenna connectors for interfacing antenna elements of the DUT with the MIMO OTA test system. The MIMO OTA test system and method can include a lens system that allows the OTA tests to be performed in a radiating near-field zone, thereby allowing a relatively small and less expensive anechoic chamber to be used in the MIMO OTA test system.

Abstract: A real-time spectrum analyzer includes an ADC for providing digitized time domain data, an acquisition control unit for selectively acquiring the time domain data, a processing unit and a display unit. The processing unit includes a domain conversion engine configured to convert the acquired time domain data to frequency domain data, first and second display engines configured to generate first and second display data according to first and second display modes, a frequency content based trigger unit configured to generate a frequency content based trigger signal when the frequency domain data meet a first predetermined trigger condition, and a trigger based enabler configured to generate an enable signal for selectively gating the second display engine in response to the frequency content based trigger signal, such that the second display engine stops generating the second display data, while the first display engine continues to generate the first display data.

Abstract: An apparatus for inspecting a substrate is described. The apparatus includes an X-Y stage that supports a substrate to be inspected and is operable to move a substrate supported thereby in X and Y directions; and an imaging system including a plurality of beam columns operable to irradiate regions of a substrate supported by the X-Y stage with beams of energy, respectively, discrete from one another. Respective ones of the beam columns are movable relative to others of the electron beam columns.

Abstract: An optical modulator that is adapted to modulate a light signal at very high RF frequencies and provide the modulating RF signal to equipment separate from the modulator is disclosed. The modulator includes a Mach-Zehnder Modulator in which light loses due to the crossing of the RF waveguide conductors and the optical waveguides are reduced. In addition, problems arising from asynchrony between the RF signals and the optical signals are reduced. The modulator also reduces signal losses due to resonances in the modulator. The modulator can be configured to be used in test probes that require a compact configuration that is adapted to designs having multiple test probes that are proximate to each other.

Abstract: A system and method prevent interference caused by images resulting from mixing an incoming periodically modulated RF signal with multiple LO signals generated by a LO in a receiver system. The method includes determining tone frequencies of multiple tones and determining tone spacing between adjacent tones in the periodically modulated RF signal using a known period of modulation of the periodically modulated RF signal; identifying a sampling rate of an ADC of the receiver system; determining a DFT record size of samples provided by the ADC based on at least the tone spacing and the ADC sampling rate; and determining LO frequencies of the multiple LO signals based on at least the DFT record size and the ADC sampling rate, such that images created by respectively mixing the determined LO frequencies with portions of the periodically modulated RF signal avoid interfering with direct mixing components of the plurality of tones.

Abstract: The multi-channel signal processing device includes a multi-channel continuous waveform (CW) phase shifter module configured to generate phase control and filter interference therein for multiple local oscillator (LO) signals at a same frequency, a multi-channel up-converter module configured to up-convert the multiple LO signals to a desired frequency and filter respective image signals therein, and a multi-channel wideband mixer module configured to receive and mix the up-converted LO signals at the desired frequency from the multi-channel up-converter module with radio frequency (RF) signals.

Abstract: Exemplary embodiments of the present invention pertain to circuitry provided in a digital-to-analog converter (DAC) for carrying out measurements indicative of various performance characteristics of the DAC. In one exemplary implementation, a control circuit containing one or more switches is used to controllably route into a measurement system, a portion of a signal that straddles a boundary between a first digital data bit and a second digital data bit in a sequence of digital data bits that are received in a DAC cell of the DAC. The control circuit, which can be included in one or more DAC cells of the DAC, is connected to a branch of a differential circuit that is provided in each of the DAC cells of the DAC, in a manner that does not affect digital-to-analog conversion in the DAC cells.

Abstract: Generally, in accordance with the various illustrative embodiments disclosed herein, an RF receiver can include an error correction system that executes a signal processing procedure upon a multi-tone digital I-signal and a multi-tone digital Q-signal to derive a wideband correction matrix. The wideband correction matrix can be used to correct one or more of: an amplitude error in any one or more frequency components of an RF input signal provided to the RF receiver, a phase error in any one or more frequency components of the RF input signal, a gain mismatch error between an analog I-signal circuit portion of the RF receiver and an analog Q-signal circuit portion of the RF receiver, or a phase mismatch error between the analog I-signal circuit portion of the RF receiver and the analog Q-signal circuit portion of the RF receiver.

Abstract: A test system for testing a DUT includes a first array of probe elements located in the near field of the DUT antenna that is either mechanically translated or electrically scanned in a first direction while being electrically scanned in a second direction that is different from the first direction to sense a bounded radiation surface comprising RF signals transmitted by the DUT antenna. A test system receiver receives first near field values contained in the RF signals and inputs them to processing logic of the test system. A reference measurement apparatus of the test system detects the RF signals and obtains reference information therefrom. Processing logic of the test system uses the reference information to correct near field phase values contained in or derived from the first near field values for phase shift between the local oscillator (LO) of the DUT and the LO of the test system.

Abstract: A method of forming a connection receptacle over a substrate includes printing a first dielectric layer over the substrate between first and second transmission lines, the first dielectric layer having a tapered cross-section along a plane extending from the first transmission line to the second transmission line; disposing a conductive layer over the printed first dielectric layer; and electrically connecting the conductive layer to a conductor of the first transmission line and a conductor of the second transmission line.

Abstract: A method of determining a noise figure (NF) response of a device under test (DUT) comprises determining a frequency response of a noise receiver over a first frequency range, measuring a gain of the DUT over a second frequency range encompassing the first frequency range, measuring output-noise power of the DUT over the second frequency range, determining an estimated gain of the DUT based on the frequency response of the noise receiver and the gain of the DUT over the first frequency range, and determining the NF response of the DUT over the second frequency range based on the estimated gain and the output-noise power.

Abstract: A current measurement device is provided for use with a measurement target having a conductive path. The current measurement device includes a non-contact current sensor to be positioned adjacent the conductive path of the measurement target. A calibration current superimposing unit, including a first electrode and a second electrode to be positioned in contact with the conductive path of the measurement target, is configured to output a calibration current to flow through the conductive path between the first electrode and the second electrode. A controller, coupled to the non-contact current sensor and the calibration current superimposing unit, is configured to control the output of the calibration current from the calibration current superimposing unit, and is configured to sample a signal from the non-contact current sensor positioned adjacent the conductive path of the measurement target.

Abstract: A test system includes a single-channel signal generator configured to generate an autocorrelation test signal to be distributed to each of a plurality of RF channels of a device under test (DUT). A time offset network includes a plurality of time offset channels each corresponding to one of the plurality of RF channels of the DUT, and is configured to, in combination with the DUT, provide corresponding autocorrelation test signals each with a different time delay as respective RF channel test signals. A single-channel measurement instrument is configured to process a single-channel test signal, based upon a combination of the RF channel test signals, to independently measure at least one characteristic of each of the RF channels of the DUT. The time offset network may be configured to be coupled between the single-channel signal generator and the DUT. Or, the time offset network may be configured to be coupled between the DUT and the single-channel measurement instrument.

Abstract: A differential transmission assembly includes two metal prisms, a ground substrate, and a resistive sheet. The two metal prisms are driven differentially. Each metal prism extends along parallel lines with a space therebetween in a common direction, coplanar in a first plane, and contributing to formation of a three-dimensional electromagnetic field. The ground substrate extends in the common direction, in a second plane parallel to the first plane. The resistive sheet is disposed in a third plane aligned to be substantially perpendicular to an electric field component of a first mode of the three-dimensional electromagnetic field, and to be parallel to an electric field component of a second mode of the three-dimensional electromagnetic field.

Abstract: A three-dimensional interconnect structure having a top surface, a first coaxial conductor, and a shielded chamber is disclosed. The first coaxial conductor is filled with a solid dielectric medium. The first coaxial conductor has a segment that runs parallel to the top surface and a segment connects the first coaxial conductor to the top surface. Conductive pads on the top surface are adapted to receive a signal and couple that signal to the first coaxial conductor at the top surface. The shielded chamber contains a device connecting two conductors that are part of the three-dimensional interconnect structure to one another in that chamber. The shielded chamber is filled with the solid dielectric medium. The structure is a solid block composed of a mixture of metal structures interspersed with the solid dielectric medium.

Abstract: A receiver and method for using the same to generate phase spectra that are independent of the starting time of the sequence of digital measurements used to generate the phase spectra are disclosed. The receiver includes a first signal port adapted to receive a first test signal that includes a plurality of tones and a first ADC that generates one digital value from the first test signal in response to each clock pulse from an ADC clock. The first receiver also includes a phase clock register that includes a time stamp value that is incremented on each clock pulse from the ADC clock, and a processor that records a sequence of the digital values starting at a first time and the time stamp value at the first time.

Abstract: Trigger event detection employs a finite state machine (FSM) and interpolation of time-sampled data. A trigger event detector includes an interpolator configured to interpolate time-sampled data and to provide an interpolated sequence of data. The trigger event detector further includes an FSM that has a plurality of predefined states including a trigger event state. The FSM is configured to transition among the predefined states according to an ordered sequence of symbols corresponding to the interpolated sequence of data. A transition of the FSM into the trigger event state represents detection of a trigger event. The trigger event detection provides one or both of a real-time trigger and a post-acquisition trigger.

Abstract: A system and method: receive an input signal and output digital samples representing the input signal; store the digital samples for at least one acquisition record of the input signal in an acquisition memory; detect a trigger event in the input signal and calculate a trigger address in the acquisition memory for a digital sample corresponding to the detected trigger event; perform digital signal processing on the digital samples of the acquisition memory to produce processed digital samples; detect an edge, representing a trigger, in the processed digital samples, and determine a measured trigger time; temporarily store the processed digital samples in a buffer memory at least until the edge detector detects the edge in the processed digital samples; determine a trigger correction value in response to the measured trigger time; determine a corrected beginning address of the buffer memory from the calculated trigger address and the trigger correction value; and read the processed digital data out from the bu

Abstract: A peripheral component interconnect express (PCIe) eXtensions for instrumentation (PXIe) chassis includes a backplane, multiple peripheral slots, a mezzanine card and an integrated accelerator module. The peripheral slots are located on the backplane and configured to receive insertable PXIe peripheral modules, respectively. The mezzanine card is on the backplane and configured to accommodate at least one of connectors, integrated circuits (ICs) and signal lines incorporated in the PXIe chassis. The integrated accelerator module is on the mezzanine card within the PXIe chassis and configured to accelerate processing of signals received from the PXIe peripheral modules.

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.