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 for localizing a mobile device in a physical space based on radio signals received from transmitters in the physical space includes a step of transforming a received signal strength vector to produce a transformed received signal strength vector. Sequence based localization is performed on the transformed RSS vector with a different ideal sequence centroid table.

Binary forward error correcting (FEC) encoding is applied to a stream of input bits, to generate a stream of coded bits. The coded bits are mapped to multiple binary streams. In some embodiments, at least one coded bit is mapped to more than one of the binary streams and none of the binary streams are identical to each other. Stream-specific modulations are applied to the binary streams. Non-binary FEC encoding could be applied after the stream-specific modulations.

Binary forward error correcting (FEC) encoding is applied to a stream of input bits, to generate a stream of coded bits. The coded bits are mapped to multiple binary streams. In some embodiments, at least one coded bit is mapped to more than one of the binary streams and none of the binary streams are identical to each other. Stream-specific modulations are applied to the binary streams. Non-binary FEC encoding could be applied after the stream-specific modulations.

Binary forward error correcting (FEC) encoding is applied to a stream of input bits, to generate a stream of coded bits. The coded bits are mapped to multiple binary streams. In some embodiments, at least one coded bit is mapped to more than one of the binary streams and none of the binary streams are identical to each other. Stream-specific modulations are applied to the binary streams. Non-binary FEC encoding could be applied after the stream-specific modulations.

A method for localizing a mobile device in a physical space based on radio signals received from transmitters in the physical space includes a step of transforming a received signal strength vector to produce a transformed received signal strength vector. Sequence based localization is performed on the transformed RSS vector with a different ideal sequence centroid table.

A signal sending and demodulation method, a device, and a system are provided, relate to the field of communications technologies, and can resolve a prior-art problem of a low user throughput caused by mismatch between poor PDCCH signal demodulation performance and PDSCH signal demodulation performance. A specific solution is as follows: A base station of a serving cell obtains a first power ratio restriction set preset by a base station of at least one interfering cell; sends a preset second power ratio restriction set and the first power ratio restriction set to a terminal; and sends a second original PDCCH signal to the terminal, where a current value of a second power ratio of the second original PDCCH signal is an element selected from the second power ratio restriction set. Embodiments of the present invention are used for signal demodulation.

A method and a communication receiver have been described for calculating log-likelihood ratios in a communication receiver. The log-likelihood ratio is calculated for each bit of one or more subsymbols of each of the one or more spatial streams by computing effective noise on one or more spatial streams after considering noise terms resulting from MIMO detection estimates of the subsymbols on each spatial stream. Finally, signal to noise ratio is determined for one or more spatial streams from the effective noise and scaling bit log-likelihood ratios with the signal to noise ratio.

A method and a communication receiver have been described for calculating log-likelihood ratios in a communication receiver. The log-likelihood ratio is calculated for each bit of one or more subsymbols of each of the one or more spatial streams by computing effective noise on one or more spatial streams after considering noise terms resulting from MIMO detection estimates of the subsymbols on each spatial stream. Finally, signal to noise ratio is determined for one or more spatial streams from the effective noise and scaling bit log-likelihood ratios with the signal to noise ratio.

Block-encoded transmissions of a multi-antenna terminal unit are effectively detected in the presence of co-channel interfering transmissions when the base station has a plurality of antennas, and interference cancellation is combined with maximum likelihood decoding. More specifically, the signals received at the base station antennas are combined in a linear combination that relates to the channel coefficients between the various transmitting terminal units and the base antennas. By selecting proper coefficients for the linear combination and choosing probable transmitted signals that minimize a minimum mean squared error function, the signals of the various terminal units are canceled when detecting the signal of a particular unit. In another embodiment of the invention, the basic approach is used to obtain an initial estimate of the signals transmitted by one terminal unit, and the contribution of those signals is removed from the received signals prior to detecting the signals of other terminal units.