Methods, systems, and devices for wireless communications are described. A base station may associate a first port and a second port each with a set of antenna elements based on a first and a second linear precoding vector, where the phases of the ports are coherent. The base station may generate coefficients indicating a first combination and a second combination of a first data set for a first user equipment (UE) and a second data set for a second UE. In some cases, the base station may apply the first linear precoding vector to the first combination, apply the second linear precoding vector to the second combination, and transmit the first combination using a first transmission beam corresponding to the first port and the second combination using a second transmission beam corresponding to the second port to the first and second UEs.

Disclosed herein is a method for detecting a covert channel in wireless communication. The method includes setting a wireless communication specification, detecting a covert timing channel, and detecting a covert storage channel.

A transmitting apparatus is disclosed. The transmitting apparatus includes an encoder to perform channel encoding with respect to bits and generate a codeword, an interleaver to interleave the codeword, and a modulator to map the interleaved codeword onto a non-uniform constellation according to a modulation scheme, and the constellation may include constellation points defined based on various tables according to the modulation scheme.

The present invention provides methods, apparatus and systems for improving a systems-level data rate on a communications link such as the orthogonal frequency division multiplexed multiple access (OFDMA) downlink used in WiFi and LTE cellular/wireless mobile data applications. The present invention preferably uses a form of multilevel coding and decoding known as tiled-building-block encoding/decoding. With the present invention, different receivers coupled to different parallel downlink channels with different channel qualities decode different received signal constellations at different levels of resolution. This allows the downlink of the OFDMA system to operate with a significantly higher data rate, thus eliminating existing inefficiencies in the downlink and significantly increasing system level bandwidth efficiency.

This application provides a signal sending method, a signal receiving method, and a related apparatus. The method includes: modulating a bit stream to generate a modulated symbol, where a modulation order of the bit stream is n, a value of the modulated symbol is one of a plurality of complex number sets, the complex number set includes Y = 2.sup.n complex numbers, and the complex number set meets: a ratio of a real part of a first complex number with a largest absolute value of the real part to a real part of a second complex number with a smallest absolute value of the real part is equal to M:N, where M and N are positive integers, a greatest common divisor of M and N is 1.

A signal detection method for a MIMO-OFDM wireless communication system includes obtaining a channel matrix of each subcarrier for each MIMO-OFDM data packet; receiving a reception vector of each subcarrier; performing MIMO detection for a first OFDM symbol and channel matrix preprocessing to generate a global dynamic K-value table; performing MIMO detection for each subsequent OFDM symbol, the MIMO detection includes: performing the following steps for each subcarrier of a current OFDM symbol: transforming the reception vector of the current subcarrier into a LR search domain; and obtaining a LR domain candidate transmission vector of the current subcarrier, a K-value applied to each search layer of the current subcarrier during the K-best search is a global dynamic K-value in the global dynamic K-value table corresponding to the search layer.

An aspect of present invention discloses a transceiver processing hardware (“TPH”) which is configured to process wireless information based on a constellation map. The TPH includes a minimum mean square error (“MMSE”), an inverse discrete Fourier transform (“IDFT”), and a demapper. The MMSE provides estimation of received bit stream, and the IDFT generates a list of samples associated with frequency of the bit stream. The demapper configured to discard unused constellation points includes a minimum function component (“MFC”) and a special treatment component (“STC”). While MFC is able to receive a bit stream representing a symbol corresponding to a quadrature amplitude modulation (“QAM”), the STC is configured to force one or more infinity values to facilitate generation of an LLR value representing a logic value of the symbol.

Example wireless communication methods and apparatus are described. In one example method, a relay device receives a first signal sent by a first device, where the first signal carries a plurality of bits. The relay device decodes the first signal to determine first information corresponding to each of a plurality of first bits. The first information corresponding to each first bit is determined based on a probability that the first bit is 1 and a probability that the first bit is 0. The relay device sends the first information in a second signal to a second device, so that the second device can use the first information to decode the first signal.

A signal detection method for a MIMO-OFDM wireless communication system includes obtaining a channel matrix of each subcarrier through channel estimation for each MIMO-OFDM data packet in a plurality of MIMO-OFDM data packets; receiving a reception vector of each subcarrier; performing MIMO detection for a first OFDM symbol in a MIMO-OFDM pack and channel matrix preprocessing for the channel matrix of each subcarrier to generate a global dynamic K-value table; performing MIMO detection for each subsequent OFDM symbol in the MIMO-OFDM data packet, in which the MIMO detection includes: performing the following steps for each subcarrier of a current OFDM symbol: reading channel matrix preprocessing results and reception vector of the current subcarrier; transforming the reception vector of the current subcarrier into an LR search domain; and performing K-best search for the current subcarrier to obtain an LR domain candidate transmission vector of the current subcarrier, in which a K-value applied to each search layer of the current subcarrier during the K-best search is a global dynamic K-value in the global dynamic K-value table corresponding to the search layer.

A signal detection method associated with a constellation diagram corresponding to a modulation scheme is provided for enhancing the reliability of code rate search. A mask is provided between two adjacent constellation points in the modulation scheme. The signal detection method includes: receiving a plurality of signals, and mapping the plurality of signals to the constellation diagram; when a first signal among the plurality of signals is located in the mask, discarding the first signal; and when a second signal among the plurality of signals outside located in the mask, determining a constellation point corresponding to the second signal.