A receiver module for receiving an electromagnetic signal, including an analog frontend and at least a first receiving channel and a second receiving channel is described. The receiving channels are both connected to the analog frontend, wherein the frontend is configured to receive an input signal including a symbol sequence and to forward the input signal to the receiving channels, wherein the receiving channels each include an analog to digital converter, wherein the second receiving channel includes an attenuator, wherein the first receiving channel and the second receiving channel each include a soft-input-soft-output-decoder, and wherein the soft-input-soft-output decoders each are configured to process the symbol sequence. Moreover, a data transmission system and a method for receiving an electromagnetic signal are described.

A reception device includes: a reception unit receiving transmission signals; a splitting unit splitting received signals into real component and imaginary component; a narrowing unit narrowing down possible signal point candidates of real component of the signal and imaginary component of the signal to signal point candidates based on the real component and the imaginary component of the split received signal; a signal point candidate hypothesizing unit hypothesizing one signal point candidate of real component from the signal point candidates of real component obtained by narrowing-down and hypothesizing one signal point candidate of imaginary component from the signal point candidates of imaginary component obtained by narrowing-down; and a signal estimation value calculating unit estimating real component of the signal based on the one hypothesized real component signal point candidate and estimating imaginary component of the signal based on the one hypothesized imaginary component signal point candidate.

A receiver is configured for receiving a signal including a training field and a payload over a communication channel. The receiver includes a channel estimator, a scaling factor calculator, a metric calculator and a decoder. The channel estimator is configured to estimate values of a parameter of the communication channel based on the training field of the received signal. The scaling factor calculator is configured to calculate a scaling factor based on the values of the parameter of the communication channel. The metric calculator is configured to calculate soft decoding metrics for use in decoding data carried by the payload of the received signal, including scaling the soft decoding metrics by the scaling factor. The decoder is configured to decode the data carried by the payload of the received signal using the scaled soft decoding metrics.

A receiver for receiving a signal including a plurality of symbols through a multiple input multiple output (MIMO) channel, and an operation method of the receiver are provided. The receiver includes a demodulator configured to calculate, for each physical channel, Euclidean distances of one or more of the received symbols with respect to all candidate vectors included in an initial candidate vector set and to output information about the Euclidean distances. A vector set detector may select, based on the information, one of a plurality of candidate vector sets having different sizes, as a subsequent candidate vector set for calculating a log likelihood ratio (LLR) of other symbols of the plurality of symbols or an LLR with respect to a second signal received following the first signal.

A method and an apparatus in a multiple-input multiple-output (MIMO) wireless communication system are provided. A signal is received over a channel. The channel is decomposed into a plurality of virtual channels. Symbol detection is performed on each of the plurality of virtual channels. Values are obtained for the channel. Decoding is performed using the values to output a decoded symbol value of the received signal.

The present disclosure describes methods and apparatuses for inter-radio access technology carrier aggregation. In some aspects, a user device establishes a wireless link for communicating with a base station via a first radio access technology. The user device receives an inter-radio access technology carrier aggregation communication via the wireless link in accordance with the first radio access technology. The inter-radio access technology carrier aggregation communication includes data relating to a component carrier of the wireless link that uses a second radio access technology. The user device may use the data to configure the user device for communication via the second component carrier of the wireless link.

A method of signal demodulation includes receiving, by a signal receiver, a first signal modulated by a symbol corresponding to a point in a constellation; generating, by the signal receiver and on the basis of the first signal, a first initial modulation estimate; identifying, by the signal receiver and on the basis of the first initial modulation estimate, a row or column of an initial candidate lookup table, the row or column corresponding to a region of the constellation; reading, by the signal receiver, from the row or column of the initial candidate lookup table one or more first initial candidate points of the constellation, at least one among the one or more first initial candidate points being more distant, from a center of the region, than a point, in the constellation, not among the one or more first initial candidate points, and demodulating, by the signal receiver and on the basis of the one or more first initial candidate points, the first signal.

An optical receiver is configured to receive optical signals representative of digital information over an optical communication link. The optical receiver is further configured to decode symbol estimates from an optical signal received over the optical communication link; to demap first bit estimates and second bit estimates from the symbol estimates; to decode third bit estimates from the first bit estimates using second FEC decoding of a second FEC scheme; and to decode fourth bit estimates from both the second bit estimates and the third bit estimates using first FEC decoding of a first FEC scheme. The optical receiver is further configured to use one or more of the third bit estimates to demap one or more of the second bit estimates. Concatenation of the first and second FEC schemes as described herein may relax design constraints on the second FEC scheme, which may reduce power consumption and design complexity.

An optical transmission method for processing a signal based on direct detection includes setting, by an equalizer, an adaptive equalization coefficient by performing an equalization process during a training symbol field section in a frame of a received signal, performing, by a channel estimator, channel estimation to perform an equalization process of a soft output maximum likelihood sequence equalizer (MLSE) during the training symbol field section, driving the soft output MLSE, and compensating for, by the soft output MLSE, distortion of the received signal during a data symbol field section in the frame on the basis of the adaptive equalization coefficient and an estimated result value of a channel, and recovering, by an error corrector which allows soft-decision processing to be performed, the received signal by performing error correction on the received signal in which the distortion is compensated for.

A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.