An integrated circuit for a receiving link device includes a processing device to detect, using an equalizer of the receiving link device, that a receiver (RX) pre-cursor value is outside of a threshold value based on a target RX tap value. The processing device further generates, based on the detecting, a plurality of tap messages having a plurality of up or down commands to one of decrease or increase a corresponding transmitter (TX) pre-cursor value of a transmitting link device. The processing device further causes the plurality of tap messages to be provided to a local transmitter to be transmitted to the transmitting link device. The plurality of tap messages is to cause the transmitting link device to adjust the corresponding TX pre-cursor value.

An apparatus performs a discrete Fourier transform process on M×N received signal components included in a received signal, by a unit of N received signal components; and estimates an estimated signal containing M×N estimated signal components, which are estimated values of M×N transmission signal components, on the basis of the received signal on which the discrete Fourier transform process is performed. When the estimated signal xe is newly estimated, the apparatus performs an exclusion operation of excluding an estimated value xe.sup.(k) of the M transmission signal components that constitute a k-th transmission signal group from the estimated signal xe newly estimated, and updates the estimated value xe.sup.(k) based on an intermediate signal xt.sup.(k) obtained by the exclusion operation and the received signal, thereby re-estimating the estimated signal xe.

A receiving link device includes a receiver (RX) to receive a data signal from a transmitting link device, the receiver including an equalizer to detect RX tap values and a processing device coupled to the receiver, the processing device to perform operations including: programming the receiver with information related to target RX tap values that are associated RX pre-cursors or RX post-cursors; detecting, using the equalizer, that an RX pre-cursor value is greater or less than a target RX tap value; generating, based on the detecting, a tap message including an up or a down command to decrease or increase a corresponding transmitter (TX) pre-cursor value of the transmitting link device; and causing the tap message to be provided to a local transmitter to be transmitted to a remote receiver of the transmitting link device, which causes the transmitting link device to adjust the corresponding TX pre-cursor value.

A receiving link device includes a receiver (RX) to receive a data signal from a transmitting link device, the receiver including an equalizer to detect RX tap values and a processing device coupled to the receiver, the processing device to perform operations including: programming the receiver with information related to target RX tap values that are associated RX pre-cursors or RX post-cursors; detecting, using the equalizer, that an RX pre-cursor value is greater or less than a target RX tap value; generating, based on the detecting, a tap message including an up or a down command to decrease or increase a corresponding transmitter (TX) pre-cursor value of the transmitting link device; and causing the tap message to be provided to a local transmitter to be transmitted to a remote receiver of the transmitting link device, which causes the transmitting link device to adjust the corresponding TX pre-cursor value.

A receiver unit comprising a signal input configured to receive a receive signal including a plurality of data symbols, a symbol detection circuit configured to detect a subset of data symbols, a reliability measuring circuit configured to determine a reliability value for the data symbols, a feedback loop configured to detect the subset of data symbols and the reliability value iteratively, and a signal output circuitry configured to determine output values of the subset of data symbols on the basis of the detected subset of data symbols and the determined reliability value.

An improved receiver design implements a method for modeling users in SIC turbo loop multiuser detection architectures that reduces the number of implementation cycles, and thereby reduces the computational overhead associated with computing the inverse of the received signal covariance matrix, by efficiently reusing components of a QR decomposition. By reusing some of the computational results from the previous turbo loop's equalizer calculation, the disclosed receiver significantly reduces the computational burden of updating the linear equalizer on each turbo loop. Depending on the embodiment, this reduction can be accomplished in at least two different ways, depending on the dimensionality and other aspects of the implementation.

A turbo equalization device includes equalization circuitry, which in operation, performs an equalization process M times on an input signal, M being an integer equal to or more than 1; counter circuitry, which in operation, counts an iteration number m that indicates a number of the performed equalization process, m being an integer equal to or more than 0 and equal to less than M; control circuitry, which in operation, determines an iteration number N of a decoding process for the m times equalization processed input signal according to the iteration number m of the equalization process, the decoding process using an error correcting code that uses a belief propagation algorithm, N being an integer equal to or more than 1; and decoding circuitry, which in operation, performs a decoding process N or less times on the m times equalization processed input signal.

Consistent with the present disclosure, an encoder circuit is provided at a transmit side of an optical fiber link that maps an input sequence of bits of fixed length k a sequence of symbols of a codeword of length n, such that the symbols of the codeword define a predetermined transmission probability distribution. Preferably, each symbol of the codeword is generated during a corresponding clock cycle, such that after n clock cycles, a complete codeword corresponding to the input bit sequence is output. On a receive end of the link, a decoder is provided that outputs the k-bit sequence every n clock cycles. Accordingly, buffers need not be provided at the output of the encoder and the input of the decoder, such that processing of the input sequence, codewords, and output sequence may be achieved efficiently without large buffers and complicated circuitry. Moreover, the input sequence, with any binary alphabet may be matched to a desired output distribution with any arbitrary alphabet. Accordingly, probabilistic constellation shaping may be achieved over constellations of arbitrary size. In addition, relatively long codewords, may be encoded and decoded with the apparatus and method disclosed herein. Accordingly, for a fixed SNR a higher SE (more bits per symbol) can be achieved. Alternatively, for a fixed SE, a lower SNR may be sufficient. Moreover, the resulting SE may be finely tailored to a particular optical link SNR to provide data transmission rates that are higher than the low order modulation formats that would otherwise be employed for optical signals carried by such links.

A BP detector of a wireless receiver apparatus reads a first parameter set or a second parameter set. The first parameter set includes a plurality of scaling factors and a plurality of damping factors learned together using a deep learning technique. The second parameter set includes a plurality of scaling factors and a plurality of node selection factors learned together using a deep learning technique from a memory. The BP detector executes an iterative BP algorithm that uses the first parameter set or the second parameter set in order to perform multi-user detection.

A BP detector of a wireless receiver apparatus reads a first parameter set or a second parameter set. The first parameter set includes a plurality of scaling factors and a plurality of damping factors learned together using a deep learning technique. The second parameter set includes a plurality of scaling factors and a plurality of node selection factors learned together using a deep learning technique from a memory. The BP detector executes an iterative BP algorithm that uses the first parameter set or the second parameter set in order to perform multi-user detection.