Selection of equalization coefficients to configure a communications link between a receiver in a host system and a transmitter in an optical or electrical communication module is performed by a management entity with access to management registers in the receiver and transmitter. Continuous modification of the selected equalization coefficients is enabled on the communications link after the communications link is established to handle varying operating conditions such as temperature and humidity.

The present disclosure discloses a signal equalization apparatus. A channel length estimation circuit determines a transmission channel length of the input signal such that a processing circuit retrieves predetermined feed-forward equalizer coefficients. A feed-forward equalizer equalizes the input signal according to operation feed-forward equalizer coefficients. An auto gain circuit amplifies the input signal according to an offset signal. A signal adding circuit adds the amplified input signal and a feedback adjusting signal to generate an added input signal. A data slicer generates a data-slicing result and the offset signal according to reference thresholds based on the added input signal. A feedback equalizer equalizes the data-slicing result to generate the feedback adjusting signal according to operation feedback equalizer coefficients. The feed-forward equalizer and the feedback equalizer keeps updating the equalizer coefficients such that a signal interference noise is eliminated rapidly to increase a signal and noise ratio of the system.

There is provided a method including receiving, by a multiplexer, input signals having a first rate, applying, by an equalizer in the multiplexer, equalization on the input signals passed through respective signal paths in the multiplexer, and outputting, by the multiplexer, an output signal comprising a selected signal of equalized versions of the input signals produced by the equalization, the output signal having a second rate greater than the first rate. There is further provided a device that includes a multiplexer and a signal driver having an input connected to the output of the equalizer. The multiplexer includes a plurality of inputs to receive respective input signals, an output to provide an output signal selected from among the input signals, and an equalizer to apply equalization on the input signals that are passed through the multiplexer, the equalization to provide the selected signals as equalized signals at the output of the multiplexer.

Selection of equalization coefficients to configure a communications link between a receiver in a host system and a transmitter in an optical or electrical communication module is performed by a management entity with access to management registers in the receiver and transmitter. Continuous modification of the selected equalization coefficients is enabled on the communications link after the communications link is established to handle varying operating conditions such as temperature and humidity.

According to the present invention, a transmitting station apparatus includes: a plurality of modulation units that modulates a plurality of streams into which transmission data is divided to generate a plurality of first data signals; a training signal generation unit that generates a known training signal; a linear equalization unit that linearly equalizes the plurality of first data signals using a tap coefficient for removing inter-antenna interference and inter-symbol interference and outputs second data signals on which transmission beam forming and equalization are simultaneously performed; and a plurality of transmitting station communication units that transmit the training signal or the second data signals to a receiving station apparatus and receive the tap coefficient from the receiving station apparatus, and a receiving station apparatus includes: a coefficient estimation unit that estimates a channel impulse response from the training signal and calculates the tap coefficient based on the channel impulse response; and a receiving station communication unit that receives the second data signals or the training signal and transmits the tap coefficient calculated by the coefficient estimation unit to the transmitting station apparatus.

There is provided a method including receiving, by a multiplexer, input signals having a first rate, applying, by an equalizer in the multiplexer, equalization on the input signals passed through respective signal paths in the multiplexer, and outputting, by the multiplexer, an output signal comprising a selected signal of equalized versions of the input signals produced by the equalization, the output signal having a second rate greater than the first rate. There is further provided a device that includes a multiplexer and a signal driver having an input connected to the output of the equalizer. The multiplexer includes a plurality of inputs to receive respective input signals, an output to provide an output signal selected from among the input signals, and an equalizer to apply equalization on the input signals that are passed through the multiplexer, the equalization to provide the selected signals as equalized signals at the output of the multiplexer.

All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.

Methods, systems, and devices for wireless communications are described. Generally, a base station may indicate, to a user equipment (UE), when it changes a power amplifier (PA) non-linearity model. The base station may transmit a set of parameters for the PA model, and a set of parameters for a non-linear equalizer function for the UE to use during a digital post-processing procedure (DPoD). The base station may indicate, to the UE, a lookup table, a vector of lookup tales, a set of kernels (e.g., from which the UE may estimate the coefficients of the PA model), or a set of both the kernels and the coefficients for the PA model. Similarly, for the non-linear equalizer function, the base station may indicate an explicit indication of the function, or may indicate a lookup table, or a kernels series (e.g., with or without corresponding coefficients).

All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.

The present invention relates to precoding and feedback channel information in wireless communication system. A method includes receiving a first Precoding Matrix Index (PMI) and a second PMI from a terminal; mapping one or two codewords into layers; precoding symbols mapped into the layers using a first precoding matrix derived from the first PMI and a second precoding matrix derived from the second PMI; and transmitting the precoded symbols to the terminal, wherein the reception of the first PMI is less frequent than the reception of the second PMI.