An Analog-to-Digital Converter (ADC) includes a plurality of ADC channels connected to an in-service signal input via an isolated power combiner; an on-chip circuit including a calibration source connected to the isolated power combiner; and one or more switches configured to switch the ADC between an in-service mode and a calibration mode. The one or more switches are set such that, in the calibration mode, the in-service signal input is disconnected and the on-chip circuit is connected to the isolated power combiner, and, in the in-service mode, the in-service signal input is connected and the on-chip circuit is disconnected to the isolated power combiner. In the calibration mode, the on-chip circuit is configured to provide a test signal to the plurality of ADC channels for a determination of interleave errors in the plurality of ADC channels.

A system and method for performing discrete frequency transform including a pair of single-bit analog to digital converters (ADCs), a phase converter, a memory, a discrete frequency transform converter and summation circuitry. The ADCs convert an analog input signal into N pairs of binary in-phase and quadrature component samples each being one of four values at a corresponding one of four phases. The phase converter determines a phase value for each pair of component samples. The memory stores a set of discrete frequency transform coefficient values based on N. The discrete frequency transform converter uses a phase value and a pair of discrete frequency transform coefficient values retrieved from the memory for a selected frequency bin to determine a discrete frequency component for each pair of phase component samples. The summation circuitry sums the corresponding N frequency domain components for determining a frequency domain value for the selected frequency bin.

A method for non-linearity correction includes receiving a first output signal from a data signal path containing a first analog-to-digital converter and receiving a second output signal from a second analog-to-digital converter. The method also includes generating first non-linearity coefficients using the first output signal and generating second non-linearity coefficients using the first and second output signals. The method further includes applying, by a non-linearity corrector in the data signal path, the first and second non-linearity coefficients to compensate for non-linearity components in a digitized signal output from the first analog-to-digital converter to generate a corrected digitized signal.

An automated test equipment for analyzing an analog time domain output signal of an electronic device under test includes: an analog-to-digital converter configured for converting an analog time domain signal; a sampling clock configured for producing a clock signal; a time-to-frequency converter configured for converting the digital time domain signal into a digital frequency domain signal so that the digital frequency domain signal is represented by frequency bins; a memory device configured for storing a set of empirically determined operating parameters; and a jitter components removal module for removing jitter components produced by the analog-to-digital converter, wherein the jitter removal module is configured for subtracting the lower spur and the upper spur of each frequency bin of the frequency bins from the digital frequency domain signal so that the cleaned digital frequency domain signal is produced.

Systems and methods are disclosed for improving data channel design by applying transform domain analytics to more reliably extract user data from a signal. In certain embodiments, an apparatus may comprise a channel circuit configured to receive an analog signal at an input of the channel circuit, and sample the analog signal to obtain a set of signal samples. The channel circuit may further apply a filter configured to perform transform domain analysis to the set of signal samples to generate a first subset of samples, the first subset including fewer transitions and having a higher signal to noise ratio (SNR) than the set of signal samples. The channel circuit may detect first bit transform domain representation values from the first subset, and determine channel bit values encoded in the analog signal based on the set of signal samples and using the first bit transform domain representation values detected from the first subset as side information.

A system and method for performing discrete frequency transform including a pair of single-bit analog to digital converters (ADCs), a phase converter, a memory, a discrete frequency transform converter and summation circuitry. The ADCs convert an analog input signal into N pairs of binary in-phase and quadrature component samples each being one of four values at a corresponding one of four phases. The phase converter determines a phase value for each pair of component samples. The memory stores a set of discrete frequency transform coefficient values based on N. The discrete frequency transform converter uses a phase value and a pair of discrete frequency transform coefficient values retrieved from the memory for a selected frequency bin to determine a discrete frequency component for each pair of phase component samples. The summation circuitry sums the corresponding N frequency domain components for determining a frequency domain value for the selected frequency bin.

Systems and methods are disclosed for improving data channel design by applying transform domain analytics to more reliably extract user data from a signal. In certain embodiments, an apparatus may comprise a channel circuit configured to receive an analog signal at an input of the channel circuit, and sample the analog signal to obtain a set of signal samples. The channel circuit may further apply a filter configured to perform transform domain analysis to the set of signal samples to generate a first subset of samples, the first subset including fewer transitions and having a higher signal to noise ratio (SNR) than the set of signal samples. The channel circuit may detect first bit transform domain representation values from the first subset, and determine channel bit values encoded in the analog signal based on the set of signal samples and using the first bit transform domain representation values detected from the first subset as side information.

A method and an apparatus for determining and compensating respective harmonic distortions of digital to analog and analog to digital conversions are described. A signal from a digital to analog converter is passed through a plurality of calibration paths. Output signals from each calibration path, converted by an analog to digital converter, are analyzed in order to determine the harmonic distortions introduced by each side of the chain separately. One embodiment represents a digital sine generator which has harmonic distortions of its analog output continually compensated. Another embodiment compensates harmonic distortions introduced by an analog to digital converter in order to measure harmonic distortions of an analog signal precisely. Other embodiments are described and shown.

A non-linearity correction circuit includes a non-linearity coefficient estimation circuit. The non-linearity coefficient estimation circuit includes a data capture circuit, a non-linearity term generation circuit, a time-to-frequency conversion circuit, a bin identification circuit, a residual non-linearity conversion circuit, and a non-linearity coefficient generation circuit. The non-linearity term generation circuit is coupled to the data capture circuit. The time-to-frequency conversion circuit is coupled to the data capture circuit and the non-linearity term generation circuit. The bin identification circuit is coupled to the time-to-frequency conversion circuit. The residual non-linearity conversion circuit is coupled to the bin identification circuit. The non-linearity coefficient generation circuit is coupled to the bin identification circuit and the residual non-linearity conversion circuit.

A DAC error measurement apparatus includes: an ADC and a feedback DAC, where a measurement input of the ADC includes a square wave signal with a constant frequency, a direct-current signal at a constant logical level, and an analog output of the feedback DAC; a measurement selection module, configured to provide a measured digit in a digital output to a separately selected source cell, and provide remaining digits in the digital output to remaining source cells, where the measured digit is a flippable digit, and the remaining digits are non-flipping digits; and a measurement module, configured to measure an amplitude of the digital output based on the digital output. One flipping digit in the digital output is the measured digit, and the remaining digits are the non-flipping digits, such that the measurement selection module may separately select one source cell to receive the measured digit.