H04L25/061

Low noise quantized feedback configuration
10965311 · 2021-03-30 · ·

Described herein is an improved apparatus for increasing the performance of a modulator, which may function as an ADC. In one embodiment, the modulator comprises a voltage to current converter, a capacitor connected between two outputs of the voltage to current converter to receive a differential input current, and a switch that can switch between connecting each output of the voltage to current converter to ground while disconnecting the other output of the voltage to current converter. In this embodiment, the modulator has no common mode control loop, and no reference current. This results in decreased complexity, i.e., fewer components, as well as reduced noise.

Real time phase error detection in quadrature demodulators

An apparatus for detecting a Q-demodulator's real-time phase and offset error includes an RF signal path configured to receive an RF signal from an RF component, a first chopper to chop the RF signal at a first frequency to generate a chopped RF signal, an LO signal path configured to receive an LO signal, a second chopper to chop the LO signal at a second frequency to generate a chopped LO signal, a summing mechanism to combine the chopped LO signal to the chopped RF signal into a combination signal. The apparatus further includes a Q-demodulator comprising a phase shifter configured to shift a phase of the combination signal and a phase of the LO signal, and a mixer configured to multiply the shifted combination signal by the shifted LO signal to generate a baseband signal, and at least two filters configured to extract different signals contained in the baseband signal for analysis.

Nonlinear receiver, asymmetric decision feedback equalization circuit and method

The present disclosure provides a non-linear receiver, an asymmetric decision feedback equalization circuit and method, including: converting an optical signal emitted by a laser device into an electrical signal; obtaining a compensation amplitude of a current data in the electrical signal by obtaining an actual amplitude of the current data, and compensating the current data based on a logic value of k prior data of the current data and a feedback coefficient corresponding to the prior data; comparing the compensation amplitude of the current data with a decision threshold to determine the logic value of the current data; the feedback coefficient is an absolute value of an influence amount of the prior data on an amplitude of the current data, and k is a positive integer. The present disclosure can overcome the bit error problem of the receiver and reduce jitter of the clock recovered by the clock recovery circuit.

Receiver/transmitter co-calibration of voltage levels in pulse amplitude modulation links
10892920 · 2021-01-12 · ·

A driver circuit of a PAM-N transmitting device transmits a PAM-N signal via a communication channel, wherein N is greater than 2, and the PAM-N signal has N signal levels corresponding to N symbols. A PAM-N receiving device receives the PAM-N signal. The PAM-N receiving device generates distortion information indicative of a level of distortion corresponding to inequalities in voltage differences between the N signal levels. The PAM-N receiving device transmits to the PAM-N transmitting device the distortion information indicative of the level of the distortion. The PAM-N transmitting device receives the distortion information. The PAM-N transmitting device adjusts one or more drive strength parameters of the driver circuit of the PAM-N transmitting device based on the distortion information.

Tracking voltage reference for single ended receiver
10892758 · 2021-01-12 · ·

A receiver includes an input node coupled to receive an analog signal, a first switch coupled between the input node and a first node, a second switch coupled between the input node and a second node, a first resistive element coupled between the first node and a reference node, a second resistive element coupled between the second node and the reference node, a first capacitive element coupled to the first node, and a second capacitive element coupled to the second node. The receiver also includes a comparator having a first input coupled to the input node to receive the analog signal, and a second input coupled to the reference node to receive a reference voltage, wherein an output of the comparator controls the first and second switches.

Identification device and identification method

An identification device includes: M transmission antenna elements each of which transmits a first transmission signal to a predetermined area including a first living body; N receivers disposed surrounding the predetermined area, and each including a reception antenna element and receiving, using the reception antenna element, a first reception signal including a reflection signal obtained as a result of the first transmission signal being reflected by the first living body, during a predetermined period; a memory storing teacher signals which are MN second reception signals obtained about a second living body; and a circuit which calculates a plurality of correlation coefficients from the teacher signals and MN first reception signals obtained as a result of each of the N receivers receiving the first reception signal, performs biometric authentication of the first living body, and identifies the first living body and the second living body as identical.

NONLINEAR RECEIVER, ASYMMETRIC DECISION FEEDBACK EQUALIZATION CIRCUIT AND METHOD

The present disclosure provides a non-linear receiver, an asymmetric decision feedback equalization circuit and method, including: converting an optical signal emitted by a laser device into an electrical signal; obtaining a compensation amplitude of a current data in the electrical signal by obtaining an actual amplitude of the current data, and compensating the current data based on a logic value of k prior data of the current data and a feedback coefficient corresponding to the prior data; comparing the compensation amplitude of the current data with a decision threshold to determine the logic value of the current data; the feedback coefficient is an absolute value of an influence amount of the prior data on an amplitude of the current data, and k is a positive integer. The present disclosure can overcome the bit error problem of the receiver and reduce jitter of the clock recovered by the clock recovery circuit.

Data transceiving method and apparatus

A data transceiving method includes: receiving a first reference signal transmitted on a subcarrier in a target physical resource block, and performing, according to a first mapping rule, corresponding processing on the first reference signal received from the subcarrier in the target physical resource block, where the first mapping rule defines at least mapping of the first reference signal to 10 specified subcarriers in a physical resource block, none of the 10 specified subcarriers are in a DC subcarrier candidate set, and the first reference signal includes a PCRS. In the embodiments of this application, only the 10 specified subcarriers in the physical resource block that are not used as DC subcarriers are selected to transmit the first reference signal, and no additional DC subcarrier is set. In this way, a quantity of downlink subcarriers in a system does not change dynamically.

RECEPTION DEVICE, COMMUNICATION SYSTEM, AND METHOD FOR CALCULATING LIKELIHOOD OF MODULATION SIGNAL

A reception device according to the present invention includes: a signal division unit; a maximum-likelihood point search unit; a maximum-likelihood point search unit; a replica-vector calculation unit; a replica-vector calculation unit; and a likelihood calculation unit. Wherein, the signal division unit divides a reception signal including a plurality of multiplexed signals respectively into a real component and an imaginary component; the maximum-likelihood point search unit narrows down candidate signal points; the maximum-likelihood point search unit to narrows down candidate signal points; the a replica-vector calculation unit calculates a first replica vector by using the first candidate signal point; the replica-vector calculation unit calculates a second replica vector by using the second candidate signal point; and the likelihood calculation unit calculates a likelihood of the modulation signal by using the first replica vector and the second replica vector.

Signal filtering and signal processing apparatus and method

A signal processing method, a signal filtering apparatus, and a signal processing apparatus are provided. An input signal may be input into a filter having a passband, a superfluous signal of the passband may be output from the filter, and a target signal may be obtained by subtracting the superfluous signal from the input signal.