Patent classifications
H04L25/03057
Comparator and Decision Feedback Equalization Circuit
A comparator includes a first-stage circuit, a second-stage circuit, a first switching circuit and a second switching circuit. The first-stage circuit includes a first input circuit and a second input circuit. The first switching circuit is configured to control the conduction of the first input circuit, and the second switching circuit is configured to control the conduction of the second input circuit. The first input circuit is configured to generate a first differential signal in a sampling phase when being switched on. The second input circuit is configured to generate a second differential signal in a sampling phase when being switched on. The second-stage circuit is configured to amplify and latch the first differential signal or the second differential signal in a regeneration phase to output a comparison signal.
COMPARATOR AND DECISION FEEDBACK EQUALIZATION CIRCUIT
A comparator includes a second-stage circuit, a first input circuit, a second input circuit, a first cross-coupled circuit and a second cross-coupled circuit. The first input circuit is configured to generate a first data terminal voltage and a first reference terminal voltage. The first cross-coupled circuit is configured to perform mutual positive feedback on the first data terminal voltage and the first reference terminal voltage to generate a first differential signal. The second input circuit is configured to generate a second data terminal voltage and a second reference terminal voltage. The second cross-coupled circuit is configured to perform mutual positive feedback on the second data terminal voltage and the second reference terminal voltage to generate a second differential signal. The second-stage circuit is configured to amplify and latch the first differential signal or the second differential signal in a regeneration phase to output a comparison signal.
Semiconductor integrated circuit and reception device
According to one embodiment, in a semiconductor integrated circuit, a sampler is connected to an output node of a summer circuit. A shift register is connected to an output node of the sampler and includes K stages of registers, K being an integer that is equal to or larger than 3. To a control circuit, output nodes of respective registers of N-th to M-th stages among the K stages of registers are connected, N being an integer larger than 1 and smaller than K, M being an integer larger than N and equal to or smaller than K. A first switch includes one end connected to the output node of the summer circuit. A correction circuit includes a first control node that is connected to the control circuit through a first feedback line and an output node to which a second end of the first switch is connected.
LATCH CIRCUIT AND EQUALIZER INCLUDING THE SAME
A latch circuit and an equalizer including the same are provided. The equalizer includes: an even data path configured to receive a reception data signal and including a first summing circuit and a first latch circuit; and an odd data path configured to receive the reception data signal and including a second summing circuit and a second latch circuit. An even data signal output from the first latch circuit is configured to be input to the second summing circuit, and an odd data signal output from the second latch circuit is configured to be input to the first summing circuit. Each of the first latch circuit and the second latch circuit includes a latch and a multiplexer.
SUMMING CIRCUIT AND EQUALIZER INCLUDING THE SAME
Provided are a summing circuit and an equalizer including the summing circuit. The summing circuit includes: a reference signal generator generating a first reference signal and a second reference signal, based on a coefficient code; a first non-overlap clock buffer generating a first switching signal and a second switching signal by using the first reference signal; and a first current source receiving the first switching signal and the second switching signal generated by the first non-overlap clock buffer, generating a first output current by using a bias voltage, and outputting the first output current to an output line, wherein the first switching signal includes a switching signal and a complementary switching signal that is a complementary signal to the switching signal, and wherein a logic low period of the second switching signal is included in a logic high period of the complementary switching signal of the first switching signal.
Methods, systems and apparatus for hybrid signal processing for pulse amplitude modulation
A method to implement hybrid signal processing includes steps for receiving an analog signal at a receiver frontend, sampling the received analog signal and storing the analog sampled signals using a plurality of sampling circuitries inside the receiver frontend. Then, processing the plurality of analog sampled signals using interleaved feed-forward equalizers (FFEs) to provide FFE interleaved sampled signal values corresponding to each of the sampling circuitries. Then, processing the analog sampled signals at an interleaved Decision Feedback Equalizer (DFE) to obtain DFE interleaved sampled signal values, summing each of the FFE interleaved sampled signal values with output from one of the DFE interleaved sampled signal values to provide equalizer output signal values, and digitizing the equalizer output signal values to provide digital data bits corresponding to each of the equalizer output signal values. Implementations of the method as a hybrid communication system, system-on-a-chip, and computer readable memory are also disclosed.
EQUALIZATION AND ESTIMATION PROCESSING IN WIRELESS DEVICES
Millimeter-wave (mmWave) and sub-mmWave technology, apparatuses, and methods that relate to transceivers and receivers for wireless communications are described. The various aspects include an apparatus of a communication device including one or more antennas configured to receive an RF signal and an ADC system. The ADC system includes a 1-bit ADC configured to receive the RF signal, and an ADC controller circuitry configured to measure a number of positive samples in the received RF signal for a plurality of thresholds of the 1-bit ADC, estimate receive signal power associated with the received RF signal based on the measured number of positive samples, determine a direct current(DC) offset in the received RF signal using the estimated received signal power, and adjust the received RF signal based on the determined DC offset.
EXPLICIT SOLUTION FOR DFE OPTIMIZATION WITH CONSTRAINTS
A method of equalizing a communication link includes setting a number of coefficients equal to a required number of coefficients, determining a number of pulse responses for a waveform, the number of pulse responses being greater than the number of coefficients, setting all values in a set of values to zero, the set of values having a number of values equal to the number of coefficients, repeating, until all values in the set of values have been assigned, determining a current lowest parameter in a set of given parameters, using a position of the current lowest parameter in the set of given parameters as an index, determining a minimum value between a first term in the set of given parameters multiplied by a main pulse response minus a summation of each parameter in the set of parameters multiplied by each value in the set of values, divided by the current lowest parameter, and a corresponding pulse response, and assigning the minimum value to the value in the set of values having a position equal to position of the current lowest parameter, and determining a value of each coefficient in a set of coefficients by multiplying each value in the set of values with the sign of a corresponding pulse response in the number of pulse responses; defining an equalizer having a number of taps equal to the number of coefficients, each tap having a value based on the corresponding coefficient; and applying the equalizer to a waveform received through the communication link to produce an equalized waveform. A test and measurement device is also disclosed.
Digital noise-shaping FFE/DFE for ADC-based wireline links
Apparatus and associated methods relate to an ADC-based digital receiver including a feedforward equalizer (FFE) that has m precursor taps and n postcursor taps to equalize the precursor portion, and to adapt postcursor intersymbol interference (ISI) through a predetermined equalization coefficient selected to counteract the noise boosting effect associated with the precursor equalization. In an illustrative example, the receiver may dynamically balance noise and ISI through adaptively determining a coefficient hp.sub.1 of a first postcursor tap of a first FFE and a coefficient h.sub.1 of a first postcursor tap of a second equalizer adapted to substantially reduce or eliminate additional ISI introduced by the first FFE. The first FFE may optimize ISI removal and noise reduction, for example. One of the coefficients h.sub.1 and hp.sub.1 may be predetermined, and then the other coefficient may be iteratively adapted to trade off precursor ISI and postcursor ISI to minimize BER.
COMMUNICATION SYSTEM, RECEIVER, EQUALIZATION SIGNAL PROCESSING CIRCUIT, METHOD, AND NON-TRANSITORY COMPUTER READABLE MEDIUM
A detector coherent-receives a signal being transmitted from a transmitter. A filter group includes a plurality of filters connected in series along a signal path of a reception signal. The plurality of filters include a plurality of non-linear distortion compensation filters and one or more linear distortion compensation filters. A coefficient updating unit controls a filter coefficient of the plurality of non-linear distortion compensation filters and a filter coefficient of at least some of the linear distortion compensation filters. The coefficient updating unit adaptively controls the filter coefficient, by using an error back propagation method, based on a difference between an output signal being output from the filter group and a predetermined value of the output signal.