Abstract: A wireless reception device is notified of whether a multi-user MIMO signal transmitted from a wireless transmission device has undergone linear precoding or non-linear precoding without increasing the amount of control information. A wireless transmission device having a plurality of transmit antennas 303, for transmitting spatially multiplexed signals to a plurality of wireless reception devices includes a group construction unit 307 configured to classify the wireless reception devices into a plurality of groups and to determine a precoding scheme for each of the groups, a selection unit 315 configured to select one group from among the groups, and a precoding unit 323 configured to precode transmit data addressed to each of wireless reception devices belonging to the selected group, using a precoding scheme determined for the selected group.

Abstract: A terminal apparatus can be notified whether an MU-MIMO signal transmitted from a base station apparatus is linear-precoded or nonlinear-precoded by using effective signaling. According to the present invention, the base station apparatus decides whether the nonlinear precoding is used in an own cell, includes the decided nonlinear precoding setting information in system information or a layer 3 message, and notifies the terminal apparatus of the decided nonlinear precoding setting information by using a physical broadcast channel, a physical downlink share channel, or the like. The terminal apparatus performs a demodulation process for user data destined for the own terminal apparatus based on the nonlinear precoding setting information acquired from the notified system information or layer 3 message.

Abstract: The present invention switches an interference suppression system between a linear precoding and a nonlinear precoding in accordance with a communication environment. A wireless transmission apparatus is provided with a plurality of transmission antenna units (303), and multiplexes spatially and transmits a plurality of series of data with respect to at least one wireless reception apparatus, and includes a selection unit (307) configured to select any one precoding system from a plurality of types of precoding systems and a precoding unit (315) configured to carry out precoding with respect to the plurality of series of data using the selected precoding system. In addition, the selection unit selects either of a first precoding system carrying out linear processing with respect to the plurality of series of data or a second precoding system carrying out nonlinear processing with respect to the plurality of series of data.

Abstract: It is intended to provide a transmission device, a reception device and a communication system capable of improving transmission characteristics by performing packet combining by HARQ in MU-MIMO transmission using non-linear precoding. In a case of receiving NAK from any of terminal devices (400), a base station device (100) retransmits a packet, in which an error occurs, addressed to this terminal device. The base station device (100) transmits the data to be retransmitted together with other transmission data addressed to a different terminal device or addressed to the own terminal device by spatial multiplexing transmission with MU-MIMO. At this time, for the retransmission data, precoding is performed such that a perturbation term same as a perturbation term which has been added to this data by non-linear precoding at the time of initial transmission is added.

Abstract: A base station device according to the present invention receives wireless frames transmitted by terminal devices in nearby cells, estimates the state of the propagation channels between the terminal devices in the nearby cells and itself, based on the received signals thereof, and performs precoding on transmission data addressed to terminal devices in its own cell, based on the estimation results of the propagation channel state, and transmits.

Abstract: To realize transmission performances equivalent to those of an MU-MIMO BLAST ZF-THP system without increasing a signal processing amount in a base station apparatus in a downlink MU-MIMO transmission system. A transmission apparatus is provided with a plurality of transmission antennas, generates a transmission signal addressed to each reception apparatus based on information indicating spatial correlation of channels to and from a plurality of reception apparatuses, space-multiplexes the generated each transmission signal in the same wireless resource, and transmits it to each reception apparatus.

Abstract: In a codebook-based closed loop type MIMO, improvement for complexity in a mobile station apparatus, and reduction of amount of overhead needed for notification from the mobile station apparatus should be provided. A wireless transmission apparatus that includes a plurality of transmission antennas, performs precoding on a data signal for each of a plurality of reception apparatuses and spatially multiplexes and transmits the signal after the precoding. The wireless transmission apparatus performs sharing a codebook describing a plurality of linear filters associated with each other is shared with the each reception apparatus, and precoding on the data signal for each reception apparatus, based on a first linear filter that is extracted from the codebook in each reception apparatus based on the association and that is notified from each reception apparatus.

Abstract: The disclosed is a transmission device including a plurality of transmission antennas for transmitting signals in the same channel at the same time point to a plurality of reception devices, characterized by including: a dedicated reference signal generator configured to generate dedicated reference signals for the respective reception devices; a data signal generator configured to generate data signals for the respective reception devices; a spatial multiplexer configured to spatially multiplex at least some of the dedicated reference signals and at least some of the data signals; and a transmitter configured to transmit the spatially multiplexed signals.

Abstract: A base station apparatus according to the present invention is capable of adjusting antenna gains in a horizontal direction and a vertical direction of the plurality of antennas included in the base station apparatus, by adjusting a phase and an amplitude of a signal addressed and transmitted to a terminal apparatus, stores a codebook which is shared with the terminal apparatus and describes a plurality of linear filters associated with antenna gains in the horizontal direction and antenna gains in the vertical direction, acquires control information indicating at least one out of a plurality of linear filters described in the codebook, of which notification is sent from the terminal apparatus, performs precoding on the signal addressed to the terminal apparatus, based on the control information and the first codebook, and transmits the signal subjected to the precoding.

Abstract: A wireless communication system in which a base station apparatus having a plurality of transmission antennas and one or more terminal apparatuses communicate with each other is provided with at least two methods of a first feedback method and a second feedback method regarding propagation path information at the time of reception. In accordance with a communication condition between the base station apparatus and the terminal apparatus, or the function of the terminal apparatus, the terminal apparatus performs feedback by one of the two methods of the first feedback method and the second feedback method. The base station apparatus performs spatial multiplexing transmission on the basis of the propagation path information that has been fed back. Thus, in a system in which CSI is fed back for MIMO transmission, desired transmission characteristics can be efficiently obtained.

Abstract: Degradation in transmission performance due to a feedback error is lessened in a wireless communication system that performs non-linear pre-coding.

Abstract: In a wireless communication system that performs non-linear pre-coding, degradation in transmission performance due to a feedback error is improved. The terminal device according to the present invention is a terminal device which receives radio signals that are space-multiplexed and on which non-linear pre-coding is performed, from a base station device including multiple antennas, the terminal device including: a channel state estimator 53 that estimates channel state information on a channel between the terminal device and the base station device; a terminal antenna module 51 that acquires a linear filter that is calculated in the base station device; and a channel equalization module 57 that performs channel equalization processing on the radio signals that are received at a first point in time, based on the channel state information at a second point in time that precedes the first point in time and on the linear filter.

Abstract: A terminal device notifies a base station device about control information associated with a receive quality of the terminal device. The base station device performs data modulation on a plurality of pieces of transmit data for the terminal device, by using a plurality of different data modulation schemes one by one, based on the control information, and spatially multiplexes the plurality of pieces of transmit data after the data modulation over a single wireless resource and transmits a spatially multiplexed signal. The terminal device receives the signal with the plurality of pieces of transmit data spatially multiplexed, and detects desirable transmit data from the receive signal, based on a first channel matrix which represents channel state information between the base station device and the terminal device and a second channel matrix in which the first channel matrix is multiplied by a transform matrix.

Abstract: When spatial multiplexing is performed to any of a plurality of receiving antennas included in each terminal, it becomes possible to obtain excellent receiving characteristics by combining signals received by all antennas appropriately. A receiving antenna unit 28 receives channel state information from each terminal, a channel matrix H is obtained. A transmit weight/interference coefficient calculation unit 24 calculates a transmit weight and an interference coefficient based on channel matrix. The transmit weight is input to transmit weight multiplication units 17 and 23. The interference generation unit 15 generates an interference signal based on the interference coefficient. An interference subtraction unit 13 subtracts the interference signal from a desired signal. A modulo unit 14 adds a signal so that amplitude of an information signal output from the interference subtraction unit 13 falls within a constant range.

Abstract: A magnetic field rotation detection sensor that detects a rotation of a magnet, includes: a plurality of first magnetic sensor elements constituting a first bridge circuit; and a plurality of second magnetic sensor elements constituting a second bridge circuit, wherein sensitivity axes of the plurality of first magnetic sensor elements and sensitivity axes of the plurality of second magnetic sensor elements are oriented in directions where the sensitivity axes intersect each other, and the plurality of first magnetic sensor elements are disposed further inside than the plurality of second magnetic sensor elements.

Abstract: More reduction of the amount of operation than in QRM-VP is realized while maintaining transmission performance that can be achieved by VP.

Abstract: MU-MIMO is implemented with little changes in the mechanism of the DCF. There is provided a wireless terminal station apparatus that is used in a wireless communication system formed of one wireless base station apparatus and a plurality of wireless terminal station apparatus, in which grouping is performed on the wireless terminal station apparatus in such a way that the wireless terminal station apparatus belongs to any one of a plurality of groups, and the wireless terminal station apparatus includes a backoff controlling portion that performs control such that a backoff value at the time of random backoff, the backoff value of the wireless terminal station apparatus belonging to at least one group, is selected from a set of candidates for a backoff value which is a set of values formed of predetermined limited numbers.

Abstract: When signals received by receiving antennas included in each terminal are subjected to MMSE combining, it is configured that each terminal is able to grasp position of desired signal in signal vector obtained after combining. A base station 100 receives by a receiving antenna 23 from the terminal apparatus channel state information between a transmitting antenna 16 and spatial multiplexing object antennas included in each terminal apparatus. A transmit weight calculation unit 19 calculates a transmit weight for performing spatial multiplexing transmission to the terminal apparatus based on the channel state information. Transmit weight multiplication unit s 12 and 18 multiplies an information signal addressed to each terminal apparatus to be performed spatial multiplexing by the transmit weight. A signal multiplexing unit 13 multiplexes the information signal multiplied by the transmit weight and an information to specify the information signal that needs to be demodulated by each terminal apparatus.

Abstract: The present invention provides a technology that sets an offset value with respect to a received power of a reference signal from each of base station apparatuses, taking into consideration a difference between precoding schemes, in a wireless communication system that supports multiple different precoding schemes. The base station apparatus according to the present invention communicates with at least one of terminal apparatuses using the multiple different precoding schemes. The base station apparatus according to the present invention includes a transmission unit that transmits to the terminal apparatus multiple offset values that are to be added by the terminal apparatus to the received power of the reference signal from the base station apparatus, in which the multiple offset values correspond to the multiple precoding schemes, respectively.

Abstract: A filter calculating device includes a first equalization filter calculating section that generates at least a first conversion matrix and a first triangular matrix based on a channel state of a first channel; a first quasi-orthogonalization section that calculates a first unimodular matrix based on the first triangular matrix; and a second equalization filter calculating section that generates at least a second conversion matrix and a second triangular matrix based on a channel state of a second channel and the first unimodular matrix.