Implementations described herein are directed to satellite transmitters and receivers for applying OFDM-like signaling in broadband satellite transmissions. In such systems, one or more data signals may be shaped and composited into a composite data signal at an OFDM-like transmitter for transmission over a satellite channel. The data signals that are carried over the satellite channel by the composited signal may have their own carrier, and each signal may carry multiple OFDM subcarriers. Further implementations are directed to correcting for distortion in satellite communications systems that utilize OFDM-like signaling. This distortion correction may account for the linear and nonlinear distortion introduced by the high power amplifier of a satellite receiving a composite signal, the linear and nonlinear distortion caused by the interaction of the signals in the composite, the linear and nonlinear distortion caused by the interaction between OFDM subcarriers, and/or the linear and nonlinear distortion caused by inter-carrier interference.

A communications apparatus to receive a composite signal including a desired signal and interferer signals, where the desired signal may include desired symbols and the interferer signals may include interferer symbols. The system may include N frameworks, each framework may include a detector to partition the desired symbols and the interferer symbols based on an interference severity into a dominant group and a non-dominant group, and to generate A Posteriori Probabilities (APP) of the desired symbols and the interferer symbols. The detector of each of the N frameworks generates the APP based on a feedback of a priori probabilities from each of the N frameworks.

Embodiments of the present disclosure relate to methods, apparatuses and computer program products for signal detection in a wireless communication system. A method implemented at a receiver device includes obtaining a set of received signals; determining a channel matrix via which the set of received signals have been transported; and detecting the set of received signals in a staged manner, wherein in a stage, the method includes detecting the set of received signals, based on the channel matrix and a detection algorithm for the stage; fixing one or more of detected symbols output from the detecting algorithm for the stage; and updating the channel matrix and the set of received signals for usage by a next stage, based on the one or more of the detected symbols that are fixed in the stage.

The present disclosure relates to a pre-5.sup.th-Generation (5G) or 5G communication system to be provided for supporting higher data rates beyond 4.sup.th-Generation (4G) communication system such as long-term evolution (LTE). An operating method of a reception device in a wireless communication system includes: receiving a signal transmitted through a plurality of antennas of a transmission device; determining an initial symbol vector based on the signal; determining a first candidate symbol vector based on a plurality of solution vectors which are obtained by a search on the initial symbol vector; determining a second candidate symbol vector by flipping at least one symbol value of the first candidate symbol vector; and determining a symbol vector transmitted from the transmission device based on at least a portion of the second candidate symbol vector.

A method and system for providing sub-band whitening are herein provided. According to one embodiment, a method estimating an interference whitening (IW) factor based on a legacy-long training field (LLTF) signal, updating the estimated IW factor during transmission of a data symbol, and scaling the data symbol based on the updated IW factor and the estimated IW factor.

A wireless receiver including a front end circuit, an adaptive threshold circuit, and a correlator. The front end circuit converts a wireless signal into a series of digital symbols. The adaptive threshold circuit provides an adaptive correlation threshold that is adapted based on a sync word. The correlator correlates the digital symbols with the sync word using the adaptive correlation threshold. The adaptive correlation threshold may be based on amplitude attenuation of the digital symbols that correspond to transitions of the sync word. The adaptive threshold circuit may be a lookup table that stores different threshold values each corresponding to one of multiple different sync words. Alternatively, the adaptive threshold circuit may be implemented as an evaluation circuit that determines the adaptive correlation threshold based on expected amplitude attenuation of the digital symbols that correspond to transitions of the sync word.

An embodiment method includes receiving, by a first user equipment (UE), a message, for a second UE, transmitted over a plurality of resource blocks (RBs) on behalf of a communications controller and determining a plurality of log-likelihood ratios (LLRs) in accordance with the received plurality of RBs. The method also includes transmitting, a subset of the determined LLRs to the second UE.

This application discloses a soft value extraction method and device applicable to an OvXDM system, and the OvXDM system. In the method, waveform coding is performed on all symbols in a hard value sequence, to generate a predictive value after overlapped coding; the symbols in the hard value sequence are reversed one by one, and overlapped coding is performed on each reversed symbol and associated symbols before and after the reversed symbol, to generate a predictive value of the reversed symbol; and for each symbol in the hard value sequence, a soft value of the current symbol is calculated based on A(.sup.+1.sup.1), where A is a coefficient related to a channel type, .sup.+1=y.sub.rxy.sup.+1, and .sup.1=y.sub.rxy.sup.1.sup.2; if y.sup.+1 is a predictive value of the symbol obtained after overlapped coding and before reversing, y.sup.1 is a predictive value of the symbol obtained after overlapped coding and reversing; and y.sub.rx is a received signal sequence.

Methods, systems, and devices for wireless communications are described. A UE may use different modulation schemes, or different modulators, for a single data stream. The set of modulators may be based on a linear combination of a function of encoded bits to be transmitted. In some cases, the UE may use a different permutation or interleaving of the function of bits with the same linear function to generate a different set of modulators. The UE may use a combination of any one or more of the described techniques for generating a set of modulators. Different modulators may be cyclically repeated over time. The UE may apply a device-specific scrambling sequence and transmit the modulated symbols on an uplink channel. The base station may use matched filters and an element-wise estimator (ESE) to compute log-likelihood ratios (LLRs) for each bit of each UE in a received signal.

A method and system for providing sub-band whitening are herein provided. According to one embodiment, a method estimating an interference whitening (IW) factor based on a legacy-long training field (LLTF) signal, updating the estimated IW factor during transmission of a data symbol, and scaling the data symbol based on the updated IW factor and the estimated IW factor.