Abstract: A digital down converter includes a low resolution mixer, a decimation filter, and a high resolution mixer. The low resolution mixer is configured to receive a digitized radio frequency signal, and apply a first down conversion to the radio frequency signal to produce an intermediate frequency signal. The decimation filter is coupled to the low resolution mixer. The decimation filter is configured to receive the intermediate frequency signal, and reduce a sampling rate of the intermediate frequency signal to produce a decimated intermediate frequency signal. The high resolution mixer is coupled to the decimation filter. The high resolution mixer is configured to receive the decimated intermediate frequency signal, and apply a second down conversion to the decimated intermediate frequency signal to produce a down converted signal.

Abstract: The disclosure provides a circuit. The circuit includes an IFFT (inverse fast fourier transform) block. The IFFT block generates a modulated signal in response to a data signal. A clip logic block is coupled to the IFFT block, and generates a clipped signal in response to the modulated signal. A first subtractor is coupled to the clip logic block and the IFFT block, and subtracts the modulated signal from the clipped signal to generate an error signal. A cyclic filter is coupled to the first subtractor, and filters the error signal to generate a filtered error signal. A second subtractor is coupled to the cyclic filter and the IFFT block. The second subtractor subtracts the filtered error signal from the modulated signal to generate a processed signal.

Abstract: A digital filter for interpolation or decimation and a device incorporating the digital filter is disclosed. The digital filter includes a filter block, a first transformation circuit coupled to the filter block and an input stream coupled to provide input values to a component selected from the filter block and the first transformation circuit. The filter block includes a pair of sub-filters having respective transformed coefficients, the respective transformed coefficients of a first sub-filter of the pair of sub-filters being symmetric and the respective transformed coefficients of a second sub-filter of the pair of sub-filters being anti-symmetric. The first transformation circuit is coupled to perform a first transformation; the filter block and the first transformation circuit together provide suppression of undesired spectral images in final outputs of the digital filter.

Abstract: A digital down converter includes a low resolution mixer, a decimation filter, and a high resolution mixer. The low resolution mixer is configured to receive a digitized radio frequency signal, and apply a first down conversion to the radio frequency signal to produce an intermediate frequency signal. The decimation filter is coupled to the low resolution mixer. The decimation filter is configured to receive the intermediate frequency signal, and reduce a sampling rate of the intermediate frequency signal to produce a decimated intermediate frequency signal. The high resolution mixer is coupled to the decimation filter. The high resolution mixer is configured to receive the decimated intermediate frequency signal, and apply a second down conversion to the decimated intermediate frequency signal to produce a down converted signal.

Abstract: The disclosure provides a circuit. The circuit includes an IFFT (inverse fast fourier transform) block. The IFFT block generates a modulated signal in response to a data signal. A clip logic block is coupled to the IFFT block, and generates a clipped signal in response to the modulated signal. A first subtractor is coupled to the clip logic block and the IFFT block, and subtracts the modulated signal from the clipped signal to generate an error signal. A cyclic filter is coupled to the first subtractor, and filters the error signal to generate a filtered error signal. A second subtractor is coupled to the cyclic filter and the IFFT block. The second subtractor subtracts the filtered error signal from the modulated signal to generate a processed signal.

Abstract: A re-sampler comprises: a plurality of multipliers configured to receive an input sample; and a plurality of accumulators coupled to the multipliers and configured to form multiplier-accumulator (MAC) units with the multipliers, wherein the MAC units are configured to: compute partial products from the input sample, accumulate the partial products over clock cycles, and sequentially generate output samples based on the computing and the accumulating. A method comprises: receiving input samples; computing partial products from the input samples; accumulating the partial products over clock cycles; and sequentially generating output samples based on the computing and the accumulating.

Abstract: Apparatus and methods disclosed herein perform gain, clipping, and phase compensation in the presence of I/Q mismatch in quadrature RF receivers. Gain and phase mismatch are exacerbated by differences in clipping between I & Q signals in low resolution ADCs. Signals in the stronger channel arm are clipped differentially more than weaker signals in the other channel arm. Embodiments herein perform clipping operations during iterations of gain mismatch calculations in order to balance clipping between the I and Q channel arms. Gain compensation coefficients are iteratively converged, clipping levels are established, and data flowing through the network is gain and clipping compensated. A compensation phase angle and phase compensation coefficients are then determined from gain and clipping compensated sample data. The resulting phase compensation coefficients are applied to the gain and clipping corrected receiver data to yield a gain, clipping, and phase compensated data stream.

Abstract: The disclosure provides a low power receiver. The receiver includes a first channel that receives an RF signal and generates an input signal. The receiver also includes a second channel and a packet detection circuit. The packet detection circuit is coupled to the first channel and the second channel. The packet detection circuit detects a valid packet in the input signal, and activates the second channel on detection of the valid packet.

Abstract: In accordance with an example, an integrated circuit includes a linear combiner having an input for receiving a signal. The linear combiner also has a plurality of operator circuits for applying weighting factors to the signal, in which a first operator circuit in the plurality of operator circuits performs a first operation on the signal using a first sub-weight of one of the weighting factors to provide a first tile output and a second operator circuit in the plurality of operator circuits performs a second operation on the signal using a second sub-weight of the one of the weighting factors to provide a second tile output. The linear combiner also has an adder having a first input coupled to receive the first tile output and the second tile outputs and providing a combined output.

Abstract: The disclosure provides a low power receiver. The receiver includes a first channel that receives an RF signal and generates an input signal. The receiver also includes a second channel and a packet detection circuit. The packet detection circuit is coupled to the first channel and the second channel. The packet detection circuit detects a valid packet in the input signal, and activates the second channel on detection of the valid packet.

Abstract: A multiplier circuit includes a partial product generation circuit, a truncation circuit, and a summation circuit. The partial product generation circuit is configured to generate a plurality of partial products for multiplying two values. The truncation circuit is coupled to the partial product generation circuit. The truncation circuit is configured to shorten at least some of the partial products by removing a least significant bit from the at least some of the partial products. The summation circuit coupled to the truncation circuit. The summation circuit is configured to sum the truncated partial products produced by the truncation circuit.

Abstract: A digital down converter includes a low resolution mixer, a decimation filter, and a high resolution mixer. The low resolution mixer is configured to receive a digitized radio frequency signal, and apply a first down conversion to the radio frequency signal to produce an intermediate frequency signal. The decimation filter is coupled to the low resolution mixer. The decimation filter is configured to receive the intermediate frequency signal, and reduce a sampling rate of the intermediate frequency signal to produce a decimated intermediate frequency signal. The high resolution mixer is coupled to the decimation filter. The high resolution mixer is configured to receive the decimated intermediate frequency signal, and apply a second down conversion to the decimated intermediate frequency signal to produce a down converted signal.

Abstract: Methods, apparatus, systems and articles of manufacture to increase an integrity of mismatch corrections in an interleaved analog to digital converter are disclosed. An example apparatus includes an instantaneous mismatch estimator that uses an output of an interleaved analog to digital converter to identify a mismatch estimate between two or more component analog to digital converters of the interleaved analog to digital converter. An integrity monitor is to cause the instantaneous mismatch estimator to avoid incorrectly providing the mismatch estimate to a filter, the integrity monitor to instruct the filter to remove the mismatch estimate when the mismatch estimate is detected to be inaccurate.

Abstract: A system includes a first tracking filter configured to track a frequency domain mismatch profile between component analog-to-digital convertors (ADCs) of an interleaved ADC (IADC), and a second tracking filter configured to a track a frequency independent timing delay mismatch and a timing delay mismatch correction error based on frequency domain mismatch profile estimates. An output of the first tracking filter determines a correction of a frequency dependent mismatch profile in an output of the interleaved ADC and an output of the second tracking filter determines a correction of the timing delay mismatch correction error in the output of the interleaved ADC.

Abstract: Circuits and methods for reducing power consumption in a half-duplex transceiver are disclosed. In an embodiment, a power management circuit of half-duplex transceiver includes direct current to direct current (DC-DC) converter and snooze mode controller. The DC-DC converter includes switching circuit and driver circuit to drive the switching circuit. The DC-DC converter provides power supply to at least one element of a transmitter sub-system of the half-duplex transceiver, and operates in snooze control modes. The snooze mode controller is coupled to the DC-DC converter and configured to generate a control signal based on at least one transceiver operating input, where the control signal causes the DC-DC converter to operate in one of the snooze control modes, the snooze control modes corresponding to snooze duty cycles and where in each snooze control mode, the switching circuit and the driver circuit remain in an OFF-state based on a respective snooze duty cycle.

Abstract: A direct down-conversion (DDC) front end receiver includes first Q-channel that filters a sum of PRBS and baseband quadrature signals to generate a first filtered quadrature signal, a second Q-channel that filters a difference of the baseband and PRBS signals to generate a second filtered quadrature signal, a first I-channel and a second I-channel, Q-path and I-path PRBS cancellation blocks for cancelling corresponding PRBS components from sum of first and second filtered quadrature signals and sum of first and second filtered inphase signals respectively, Q-path and I-path sum filter estimation blocks for estimating quadrature and inphase sum filter responses. An IQ mismatch compensation filter estimate and tracking block estimates IQ mismatch compensation filter response from estimated quadrature and inphase sum filter responses, and an IQ mismatch compensation filter filters the modified inphase signal with the IQ mismatch compensation filter response, to generate a filter compensated inphase signal.

Abstract: The disclosure provides a low power receiver. The receiver includes a first channel that receives an RF signal and generates an input signal. The receiver also includes a second channel and a packet detection circuit. The packet detection circuit is coupled to the first channel and the second channel. The packet detection circuit detects a valid packet in the input signal, and activates the second channel on detection of the valid packet.

Abstract: A re-sampler comprises a first CSD multiplier configured to receive input samples, a first accumulator coupled to the first CSD multiplier and configured to form a first MAC unit with the first CSD multiplier, a second CSD multiplier configured to receive the input samples, and a second accumulator coupled to the second CSD multiplier and configured to form a second MAC unit with the second CSD multiplier, wherein the re-sampler is configured to generate output samples based on the input samples. A method comprises receiving, by a first CSD multiplier, input samples, receiving, by a second CSD multiplier, the input samples, generating coefficients, scaling, using the first CSD multiplier and the second CSD multiplier, the input samples with coefficient vectors associated with the coefficients to form coefficient vector scaled input samples, and generating output samples based on the coefficient vector scaled input samples. The CSD multipliers may be MC-CSD multipliers.

Abstract: Suppression of interference across transceivers integrated on a single semiconductor chip. An example of a method of reducing noise in a transceiver includes introducing an adjustable time delay into a signal between a first section of a signal path into which noise may be introduced and a second section of the signal path into which noise may be introduced. The method also includes selectively adjusting the time delay and signal polarity to improve a signal-to-noise metric of the transceiver. An example of the transceiver includes a transmitter and a receiver. The transceiver also includes an adjustable time delay between a first section of a transceiver signal path into which noise may be introduced and a second section of the transceiver signal path into which noise may be introduced and circuitry for reducing noise by adjusting a value of the time delay.

Abstract: A re-sampler comprises: a plurality of multipliers configured to receive an input sample; and a plurality of accumulators coupled to the multipliers and configured to form multiplier-accumulator (MAC) units with the multipliers, wherein the MAC units are configured to: compute partial products from the input sample, accumulate the partial products over clock cycles, and sequentially generate output samples based on the computing and the accumulating. A method comprises: receiving input samples; computing partial products from the input samples; accumulating the partial products over clock cycles; and sequentially generating output samples based on the computing and the accumulating.