Patent classifications
H04L7/0079
PAM4 TRANSCEIVERS FOR HIGH-SPEED COMMUNICATION
The present invention is directed to data communication. More specifically, embodiments of the present invention provide a transceiver that processes an incoming data stream and generates a recovered clock signal based on the incoming data stream. The transceiver includes a voltage gain amplifier that also performs equalization and provides a driving signal to track and hold circuits that hold the incoming data stream, which is stored by shift and holder buffer circuits. Analog to digital conversion is then performed on the buffer data by a plurality of ADC circuits. Various DSP functions are then performed over the converted data. The converted data are then encoded and transmitted in a PAM format. There are other embodiments as well.
TIMING RECOVERY FOR OPTICAL COHERENT RECEIVERS IN THE PRESENCE OF POLARIZATION MODE DISPERSION
A timing recovery system generates a sampling clock to synchronize sampling of a receiver to a symbol rate of an incoming signal. The input signal is received over an optical communication channel. The receiver generates a timing matrix representing coefficients of a timing tone detected in the input signal. The timing tone representing frequency and phase of a symbol clock of the input signal and has a non-zero timing tone energy. The receiver computes a rotation control signal based on the timing matrix that represents an amount of accumulated phase shift in the input signal relative to the sampling clock. A numerically controlled oscillator is controlled to adjust at least one of the phase and frequency of the sampling clock based on the rotation control signal.
DISPOSABLE GLUCOSE BIOSENSOR INCLUDING AN ACTIVITY SENSOR
Example disposable biosensor devices having an activity sensor are disclosed. One example device includes a disposable biosensor that has a first electrode having a distal end to be inserted into a subcutaneous layer beneath a person's skin, the first electrode having a reactive material disposed on the distal end, and a second electrode. The disposable biosensor device also includes an activity sensor that can be activated upon an activity by the person, the activity sensor for detecting the activity and providing data about the activity. The disposable biosensor also includes a radio frequency transmitter for transmitting data obtained from the first or second electrode and the activity sensor.
Semiconductor apparatus
A semiconductor apparatus includes a pattern conversion circuit configured to generate conversion data in response to a monitoring enable signal, pattern select signals and parallel input data; a transmission circuit configured to output the conversion data as serial data in response to a plurality of clocks; a reception circuit configured to output the serial data as parallel output data in synchronization with the plurality of clocks; and a monitoring circuit configured to generate a result signal in response to the plurality of clocks, clock select signals and the serial data.
FREQUENCY OFFSET ESTIMATION AND COMPENSATION METHOD
A method of estimating an integer frequency offset and compensating for the integer frequency offset by an estimated error is provided. A frequency offset estimation method may include receiving a reception signal including PLC data and a physical layer link channel (PLC) preamble, detecting first position information on a position of a subcarrier of the PLC preamble in a frequency axis from the reception signal through a cross-correlation between the PLC preamble and the reception signal, detecting second position information on the position of the subcarrier of the PLC preamble defined in a transmission end by restoring the PLC data, and calculating a frequency offset by comparing the first position information with the second position information.
Clock recovery circuit, corresponding device and method
A clock recovery circuit comprises an input node receiving a data signal having a data rate, and a digital oscillator producing a local clock signal with a frequency higher than the data rate. A counter clocked by the local clock signal has its count value sampled and reset at the rising and falling edges of the data signal, and a storage block coupled to the counter stores a count value that is updated in response to the current sampled count value of the counter lying in an update range between lower and upper bounds. A threshold value set is produced as a function of the updated count value stored in the storage block. Sampling circuitry receives and samples the data signal, and provides a sampled version of the data signal in response to the count value of the counter reaching any of the threshold values.
Embedded Clock in Digital Communication System
A digital receiver for decoding input data having three states includes a first input coupled to a first data line, a second input coupled to a second data line, a third input coupled to a third data line, and a fourth input coupled to a fourth data line. A first decoder is coupled to a first output, wherein the first decoder is for outputting first data signals in response to the sign of input data on the first data line minus input data on the second line. A second decoder is coupled to a second output, wherein the second decoder is for outputting second data signals in response to the sign of input data on the third data line minus input data on the fourth data line.
METHOD AND APPARATUS FOR SOURCE-SYNCHRONOUS SIGNALING
A low-power, high-performance source-synchronous chip interface which provides rapid turn-on and facilitates high signaling rates between a transmitter and a receiver located on different chips is described in various embodiments. Some embodiments of the chip interface include, among others: a segmented fast turn-on bias circuit to reduce power supply ringing during the rapid power-on process; current mode logic clock buffers in a clock path of the chip interface to further reduce the effect of power supply ringing; a multiplying injection-locked oscillator (MILO) clock generator to generate higher frequency clock signals from a reference clock; a digitally controlled delay line which can be inserted in the clock path to mitigate deterministic jitter caused by the MILO clock generator; and circuits for periodically re-evaluating whether it is safe to retime transmit data signals in the reference clock domain directly with the faster clock signals.
Eye width measurement and margining in communication systems
Generally, this disclosure describes eye width measurement and margining in communication systems. An apparatus may be configured to: decouple a phase detector from a CDR loop filter of a receiver under test in response to synchronizing a margining clock signal to a receiver clock signal; apply a margining input to the loop filter, the margining input configured to shift a frequency of the margining clock signal by a constant amount related to the margining input; compare a first bit stream and a second bit stream and configured to detect an error, the first bit stream related to a transmitted bit stream; and count cycles of the receiver clock signal or the margining clock signal, wherein an eye width associated with the receiver under test is related to the margining input, the frequency of the receiver clock signal and a count of clock cycles when the error is detected.
Phase control block for managing multiple clock domains in systems with frequency offsets
A circuit for performing clock recovery according to a received digital signal 30. The circuit includes at least an edge sampler 105 and a data sampler 145 for sampling the digital signal, and a clock signal supply circuit. The clock signal supply circuit provides edge clock 25 and data clock 20 signals offset in phase from one another to the respective clock inputs of the edge sampler 105 and the data sampler 145. The clock signal supply circuit is operable to selectively vary a phase offset between the edge and data clock signals.