Abstract: A transmission method includes mapping processing, phase change processing, and transmission processing. In the mapping processing, a plurality of first modulation signals and a plurality of second modulation signals are generated using a first mapping scheme, and a plurality of third modulation signals and a plurality of fourth modulation signals are generated using a second mapping scheme. In the phase change processing, a phase change is performed on the plurality of second modulation signals and the plurality of fourth modulation signals using all N kinds of phases. In the transmission processing, the first modulation signals and the second modulation signals are respectively transmitted at a same frequency and a same time from different antennas, and the third modulation signals and the fourth modulation signals are respectively transmitted at a same frequency and a same time from the different antennas.

Abstract: A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end.

Abstract: A communication system includes: a plurality of cameras that generate image data by capturing images; a server that stores the image data generated by each of the plurality of cameras; and a plurality of transmission devices in one-to-one correspondence with the plurality of cameras. Each of the plurality of transmission devices transmits light, including, as a visible light communication signal, information related to communication for accessing a storage location at which the image data generated by a corresponding one of the plurality of cameras is stored in the server.

Abstract: A transmission device that improves data reception quality includes: a weighting synthesizer that generates a first precoded signal and a second precoded signal from a first baseband signal and a second baseband signal, respectively; a phase changer that applies a phase change of i×?? to the second precoded signal; an inserter that inserts a pilot signal into the second precoded signal applied with the phase change; and a phase changer that applies a phase change to the second precoded signal applied with the phase change and inserted with the pilot signal. ?? satisfies ?/2 radians<??<? radians or ? radians<??<3?/2 radians. Each of the first baseband signal and the second baseband signal is modulated via a modulation scheme of quadrature amplitude modulation (QAM) using non-uniform mapping.

Abstract: A transmission method simultaneously transmitting a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals, thereby improving received data signal quality for a reception device.

Abstract: A transmission device includes: a first mapper that maps a first bit stream of a first data series to generate a first modulated symbol stream of the first data series; a second mapper that maps a second bit stream of a second data series to generate a second modulated symbol stream of the second data series; a converter that subjects the second modulated symbol stream to conversion in accordance with the first modulated symbol stream; a superposition unit that superposes the first modulated symbol stream and the second modulated symbol stream at a predetermined amplitude ratio to generate a multiplexed signal, the second modulated symbol stream having been subjected to the conversion in accordance with the first modulated symbol stream; and a transmitter that transmits the multiplexed signal.

Abstract: A transmitting method includes: configuring a frame using a plurality of orthogonal frequency-division multiplexing (OFDM) symbols, by allocating a plurality of transmission data to a plurality of areas; and transmitting the frame. The plurality of areas are each identified by at least one time resource among resources and at least one frequency resource among frequency resources. The frame includes a first period in which a preamble is transmitted, and a second period in which the plurality of transmission data are transmitted by at least one of time division and frequency division. The second period includes a first area, and the first area includes a data symbol generated from first transmission data, a data symbol generated from second transmission data and subsequent to the data symbol generated from the first transmission data, and a dummy symbol subsequent to the data symbol generated from the second transmission data.

Abstract: Provided is a transmission method that improves data reception quality in radio transmission using a single-carrier scheme and/or a multi-carrier scheme. The transmission method includes: generating a plurality of first modulated signals and a plurality of second modulated signals from transmission data, the plurality of first modulated signals being signals generated using a 16QAM modulation scheme, and the plurality of second modulated signals being signals generated using uniform constellation 64QAM modulation; generating, from the plurality of first modulated signals and the plurality of second modulated signals, a plurality of first signal-processed signals and a plurality of second signal-processed signals which satisfy a predetermined equation; and changing the predetermined equation when a 64QAM modulation used to generate the plurality of second modulated signals is switched from the uniform constellation 64QAM modulation to a non-uniform constellation 64QAM modulation.

Abstract: This communication device relays a relay signal to be transmitted to and from a first communication device and a second communication device, and is connected to a first apparatus. The communication device transmits the relay signal using a first transmission slot, and also transmits, using a second transmission slot, a signal having been transmitted from the first apparatus, said signal being transmitted within the transmission period of the first transmission slot in a frequency domain different from that of the first transmission slot.

Abstract: A transmission method includes: in a first period, causing a light source to emit light having a first luminance; and in a second period, causing the light source to transmit an optical signal by causing the light source to alternately emit light having a second luminance and light having a third luminance lower than the second luminance.

Abstract: Disclosed is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals that are transmitted in the same frequency bandwidth at the same time. According to the precoding method, one matrix is selected from among matrices defining a precoding process that is performed on the plurality of baseband signals by hopping between the matrices. A first baseband signal and a second baseband signal relating to a first coded block and a second coded block generated by using a predetermined error correction block coding scheme satisfy a given condition.

Abstract: A transmission device includes: a weighting synthesizer that generates a first precoded signal and a second precoded signal; a first pilot inserter that inserts a pilot signal into the first precoded signal; a phase changer that applies a phase change of i×?? to the second precoded signal, where i is a symbol number and an integer that is greater than or equal to 0; an inserter that inserts a pilot signal into the phase-changed second precoded signal; and a phase changer that applies a phase change to the phase-changed and pilot-signal-inserted second precoded signal. ?? satisfies ?/2 radians<??<? radians or ? radians<??<3?/2 radians.

Abstract: A terminal apparatus includes a receiver and reception signal control circuitry. The receiver, in operation, receives a first downlink data signal transmitted from a first communication station and receives a second downlink data signal transmitted from a first communication station, the first downlink data signal and the second downlink data signal being received over a first downlink channel and a second downlink channel that are at least partially overlapped in time and frequency domain. The reception signal control circuitry, in operation, demodulates the received first downlink data signal and a second downlink data signal.

Abstract: An access point includes a first interface that wirelessly communicates using a first band; a second interface that wirelessly communicates using a second band; and a controller that selects one type of request to send (RTS)/clear to send (CTS) control from among three mutually different types using at least one of the first interface and the second interface, and carries out the selected one type of RTS/CTS control with a terminal.

Abstract: In a repeater device: a communication device receives position information of a forwarding source device and a forwarding destination device using a first communication scheme; based on the position information of the forwarding source device, a moving mechanism moves the repeater device to a position at which it is capable of communicating with the forwarding source device using a second communication scheme; the communication device receives data from the forwarding source device using the second communication scheme; a storage device stores the data; based on the position information of the forwarding destination device received by the communication device, the moving mechanism moves the repeater device to a position at which it is capable of communicating with the forwarding destination device using the second communication scheme, and the communication device transmits the data stored in the storage device to the forwarding destination device using the second communication scheme.

Abstract: Provided is a wireless apparatus that can coexist with a wireless communication system, in which a communicatable distance is made longer, by beam forming. This wireless apparatus comprises: a reception circuit that receives a signal using a first directivity; and a control circuit that controls transmission or stand-by of a transmission signal on the basis of reception of the signal. The reception section of the signal is set shorter than the reception section of a signal received using a second directivity.

Abstract: Disclosed are an encoder, a transmission device, and an encoding method with which the transmission amount is reduced and a deterioration in transmission efficiency is suppressed while improving reception quality when QC-LDPC or a like block encoding is used. A puncture pattern setting unit (620) searches for a puncture pattern for each integral multiple of the number of columns or for each divisor of the number of columns of a sub block matrix that forms a check matrix (H) of a QC-LDPC code, and a puncture unit (data reduction unit) (630) switches the puncture pattern for each integral multiple of the number of columns or for each divisor of the number of columns of the sub block matrix that forms the check matrix of the QC-LDPC code.

Abstract: A signal generation method is used in a transmission device that transmits a plurality of transmission signals from a plurality of antennas at the same frequency and at the same time, in the case where larger power change is performed on a first transmission signal than on a second transmission signal during generation process of the first transmission signal and the second transmission signal, the first transmission signal and the second transmission signal are mapped before the power change such that a minimum Euclidian distance between possible signal points for the first signal is longer than a minimum Euclidian distance between possible signal points for the second signal.

Abstract: Disclosed is a transmission scheme for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a precoding weight by a baseband signal after a first mapping and a baseband signal after a second mapping and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.