A digital signal processing (DSP) device includes a first fitter to equalize channel dispersion associated with signal transmission through a medium, a second filter to cancel channel reflections, and a third filter to at least reduce noise. The DSP device is a receiver DSP of the SERDES.

The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE). A method for operating a receiving device in a wireless communication system comprises determining inter-symbol interference between symbols in a received signal, determining a location of a receive detection window according to the inter-symbol interference, and demodulating the received signal based on the location of the receive detection window. A receiving device includes at least one transceiver, and at least one processor configured to determine inter-symbol interference between symbols in a received signal, determine a location of a receive detection window according to the inter-symbol interference, and demodulate the received signal based on the location of the receive detection window. A transmitting device includes at least one processor configured to estimate an equivalent channel frequency response based on characteristic information of a time-domain filter, estimate an inter-symbol interference based on the equivalent channel frequency response, and generate indication information regarding an adjustment of a location of a receive detection window.

Non-linear interference cancellation techniques are provided for wireless transceivers. Non-linear reduction of interference of a transmit signal on a received signal in a transceiver device, comprises applying the transmit signal to a first non-linear system; applying the received signal to a second non-linear system; and subtracting an output of the first non-linear system output from an output of second non-linear system output to produce an interference mitigated received signal. The first non-linear system and/or the second non-linear system can be implemented using one or more of a Volterra series and a Generalized Memory Polynomial Model. System parameters of the first non-linear system and/or the second non-linear system are adapted to reduce a power of the interference mitigated received signal.

According to an exemplary embodiment, a method of making a Hermetic transform to mitigate noise comprises: receiving over a channel signal frames comprising predetermined data and gaps comprising noise; framing the predetermined data; constructing a set of linear equations which relate a transfer function matrix of the channel to the predetermined data; determining the transfer function matrix by inverting the linear equations using a first pseudo inverse matrix; incorporating transfer function matrix into linear equations for a hermetic transform; and determining the hermetic transform using a second pseudo inverse matrix based on the predetermined data and the noise.

Various embodiments disclosed herein provide for a reciprocity based channel state information acquisition scheme for frequency division duplex wireless communications systems. By converting channel state information from a traditional frequency-time domain to a Delay-Doppler domain, the channel state information feedback overhead can be reduced since the multi-path of radio propagation is reciprocal in terms of each ray and each cluster of antenna elements. Since the surrounding objects create the same multipath fading for both uplink and downlink transmissions, modeling the channel state information in the Delay-Doppler domain, and adjusting the sign of the Doppler value (negative/positive) can account for the multipath characteristics in both uplink and downlink.

The disclosed embodiments relate to the design of an equalizer that uses both cross-coupled cascodes and inductive peaking to reduce distortion in a signal received from a communication channel by attenuating lower frequencies and amplifying higher frequencies. At lower frequencies, when the effects of inductive impedance within the equalizer are negligible, the equalizer essentially functions as a traditional cascode amplifier that presents high gain. At higher frequencies, the increases in inductive impedances within the equalizer act to boost a gain of the equalizer.

A method of Narrow-band Internet of Things physical random-access channel (NPRACH) communication includes: transmitting, from a user equipment (UE), a Narrow-band Internet of Things (NB-IoT) Orthogonal Frequency-Division Multiple Access (OFDMA) symbol using a transmit inverse fast Fourier transform (Tx-IFFT) having a first length; processing, at lower physical layer (LPHY) of a baseband unit (BBU), the NB-IoT OFDMA symbol using a receive fast Fourier transform (Rx-FFT) having a second length different from the first length to generate an Rx-FFT output; sending, from the LPHY of the BBU to upper physical layer (UPHY) of the BBU, a selected number of values of the Rx-FFT output corresponding to desired resources block in the NB-IoT OFDMA symbol; filtering, at the UPHY, intercarrier interference (ICI) from the selected number of values of the Rx-FFT output; and reconstructing, at the UPHY, the NB-IoT OFDMA symbol.

A frequency shift keying (FSK) demodulator for demodulating symbols includes correlation circuits configured to output correlation metrics based on a buffered portion of an input signal as the input signal is continuously received by the FSK demodulator. The FSK demodulator also includes a result combining stage configured to output a set of first correlation results based on correlation metrics generated for a first portion of the input signal encoding a current symbol and at least one past symbol, and a set of second correlation results based on correlation metrics generated for a second portion of the input signal encoding the current symbol and at least one next symbol; and a time combining stage configured to combine a set of delayed first correlation results with the set of second correlation results to produce a demodulation decision that returns a most likely symbol value for the current symbol.

This disclosure relates to a 5G or a pre-5G communication system to be provided to support a higher data rate following 4G communication systems such as LTE. A method according to one embodiment of the present invention is a method for attenuating interference of a signal received in a receiver of a filter bank multicarrier (FBMC) system, the method comprising the steps of: separately extracting data and a reference signal in a received FMBC symbol; obtaining a diagonal element channel of a desired symbol through a channel estimation from the extracted reference signal; generating an interference channel matrix of a non-diagonal component of the desired symbol, a diagonal component and a non-diagonal component of an interference symbol using a channel estimated diagonal component; reconfiguring to a banded channel matrix using an interference channel matrix; and attenuating the interference contained in the extracted data using the reconfigured banded channel matrix information and filter information of a transmitter of the filter bank multicarrier system.

Certain features relate to a remote antenna unit having a multi-stage isolation sub-system for isolating uplink and downlink signal paths. A multi-stage isolation sub-system in the remote antenna unit can include a first stage device that is configured to generate a cancellation signal for canceling unwanted downlink signals received at the uplink antenna. The isolation sub-system can also include a second stage device configured to generate a cancellation signal that attenuates residual noise and intermodulation products generated in the downlink path and received in the uplink path. The multi-stage isolation sub-system can combine the cancellation signals with signals received on the uplink path in order to cancel or attenuate downlink leakage signals and residual noise present on the uplink path.