Patent classifications
H04L27/01
Bandwidth constrained communication systems with frequency domain information processing
The present disclosure provides techniques for bandwidth constrained communication systems with frequency domain information processing. A bandwidth constrained equalized transport (BCET) communication system can include a transmitter, a communication channel, and a receiver. The transmitter can include a pulse-shaping filter that intentionally introduces memory into a signal in the form of inter-symbol interference, an error control code (ECC) encoder, a multidimensional fast Fourier transform (FFT) processing block that processes the signal in the frequency domain, and a first interleaver. The receiver can include an information-retrieving equalizer, a deinterleaver with an ECC decoder, and a second interleaver joined in an iterative ECC decoding loop. The communication system can be bandwidth constrained, and the signal can comprise an information rate that is higher than that of a communication system without intentional introduction of the memory at the transmitter.
Retransmission control method
A receiving station performs first signal detection processing on a received radio signal, performs a retransmission request to a transmitting station in a case in which a code error is detected in a detected radio packet for user data, and enqueues the radio packet in a reception buffer in a case in which no code error is detected. In parallel with the first signal detection processing, the receiving station performs second signal detection processing on the received signal with a longer processing delay than that of the first signal detection processing, and in a case in which no code error is detected in the detected radio packet for user data, the receiving station enqueues the radio packet in the reception buffer. The receiving station outputs, at a predetermined timing, the radio packet for user data with no code error detected, the radio packet being enqueued in the reception buffer.
Equalizer and transmitter including the same
An integrated circuit for generating an equalized signal, according to a channel, from serial data includes a shift register that extracts a symbol sequence from the serial data. A data storage stores values of an equalized digital signal corresponding to potential symbol sequences corresponding to a filter coefficient sequence. A lookup table outputs the equalized digital signal of a value corresponding to the extracted symbol sequence. A digital-to-analog converter (DAC) converts the equalized digital signal into the equalized signal. A controller refreshes the lookup table, based on at least one of values stored in the data storage and values included in the lookup table, in response to a control signal.
Equalizer and transmitter including the same
An integrated circuit for generating an equalized signal, according to a channel, from serial data includes a shift register that extracts a symbol sequence from the serial data. A data storage stores values of an equalized digital signal corresponding to potential symbol sequences corresponding to a filter coefficient sequence. A lookup table outputs the equalized digital signal of a value corresponding to the extracted symbol sequence. A digital-to-analog converter (DAC) converts the equalized digital signal into the equalized signal. A controller refreshes the lookup table, based on at least one of values stored in the data storage and values included in the lookup table, in response to a control signal.
RECEIVER FOR COMPENSATING FOR VOLTAGE OFFSET IN REAL TIME AND OPERATION METHOD THEREOF
An operation method of a receiver, which includes setting a coefficient of an equalizer based on one of a plurality of first codes, setting a coefficient of an amplifier based on one of a plurality of second codes, performing offset calibration by driving the equalizer and the amplifier based on the coefficient of the equalizer and the coefficient of the amplifier, storing an offset code corresponding to a voltage offset generated when the equalizer and the amplifier are driven, determining whether the offset calibration is completed, performing a normal operation of obtaining reception data from an input signal, in response to determining that the offset calibration is completed, and removing the voltage offset based on the offset code, in the normal operation.
RECEIVER FOR COMPENSATING FOR VOLTAGE OFFSET IN REAL TIME AND OPERATION METHOD THEREOF
An operation method of a receiver, which includes setting a coefficient of an equalizer based on one of a plurality of first codes, setting a coefficient of an amplifier based on one of a plurality of second codes, performing offset calibration by driving the equalizer and the amplifier based on the coefficient of the equalizer and the coefficient of the amplifier, storing an offset code corresponding to a voltage offset generated when the equalizer and the amplifier are driven, determining whether the offset calibration is completed, performing a normal operation of obtaining reception data from an input signal, in response to determining that the offset calibration is completed, and removing the voltage offset based on the offset code, in the normal operation.
Adaptive equalization using correlation of data patterns with errors
An integrated receiver supports adaptive receive equalization. An incoming bit stream is sampled using edge and data clock signals derived from a reference clock signal. A phase detector determines whether the edge and data clock signals are in phase with the incoming data, while some clock recovery circuitry adjusts the edge and data clock signals as required to match their phases to the incoming data. The receiver employs the edge and data samples used to recover the edge and data clock signals to note the locations of zero crossings for one or more selected data patterns. The pattern or patterns may be selected from among those apt to produce the greatest timing error. Equalization settings may then be adjusted to align the zero crossings of the selected data patterns with the recovered edge clock signal.
Adaptive equalization using correlation of data patterns with errors
An integrated receiver supports adaptive receive equalization. An incoming bit stream is sampled using edge and data clock signals derived from a reference clock signal. A phase detector determines whether the edge and data clock signals are in phase with the incoming data, while some clock recovery circuitry adjusts the edge and data clock signals as required to match their phases to the incoming data. The receiver employs the edge and data samples used to recover the edge and data clock signals to note the locations of zero crossings for one or more selected data patterns. The pattern or patterns may be selected from among those apt to produce the greatest timing error. Equalization settings may then be adjusted to align the zero crossings of the selected data patterns with the recovered edge clock signal.
SIGNAL TRANSMISSION SYSTEM FOR USE WITH EYE DIAGRAM MONITOR
A signal transmission system includes an equalization filter configured to filter an input signal based at least in part on a feedback signal, a slicer configured to generate data based on the filtered input signal at a plurality of different phases, a synchronizer configured to compute a phase delay between the input signal at each of the different phases and the data, and a pattern generator configured to generate the feedback signal at a phase adjusted by the phase delay.
SIGNAL TRANSMISSION SYSTEM FOR USE WITH EYE DIAGRAM MONITOR
A signal transmission system includes an equalization filter configured to filter an input signal based at least in part on a feedback signal, a slicer configured to generate data based on the filtered input signal at a plurality of different phases, a synchronizer configured to compute a phase delay between the input signal at each of the different phases and the data, and a pattern generator configured to generate the feedback signal at a phase adjusted by the phase delay.