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 transmission method for transmitting an emergency warning signal, pertaining to one aspect of the present disclosure, includes: generating control information, the control information including a flag indicating either presence or absence of information related to a region and, when the flag indicates presence, information related to the region; acquiring information related to emergency warning content; and generating the emergency warning signal including the control information and the information related to the emergency warning content. Thus, emergency warning (early warning) information can be transmitted with greater precision.

Abstract: A terminal (1050) includes a light receiver (151) that receives a light signal emitted by an apparatus (1000), the light signal including an identifier (SSID) of at least one base station (470); a receiver (153) that performs a reception process on the received light signal to output reception data; a data analyzer (155) that selects one base station based on the identifier of the at least one base station that is included in the reception data; and a radio device (453) that establishes a wireless connection with the selected base station (470) by using the identifier of the base station (470) and wirelessly communicates with the base station (470).

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 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: 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: Provided are a frame configuring unit configured to configure a frame using a plurality of orthogonal frequency-division multiplexing (OFDM) symbols, by allocating time resources and frequency resources to a plurality of transmission data, and a transmitter which transmits the frame. The frame includes a first period in which a preamble which includes information on a frame configuration of the frame is transmitted, a second period in which a plurality of transmission data are transmitted by time division, a third period in which a plurality of transmission data are transmitted by frequency division, and a fourth period in which a plurality of transmission data are transmitted by time division and frequency division.

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: An encoder outputs a first bit sequence having N bits. A mapper generates a first complex signal s1 and a second complex signal s2 with use of bit sequence having X+Y bits included in an input second bit sequence, where X indicates the number of bits used to generate the first complex signal s1, and Y indicates the number of bits used to generate the second complex signal s2. A bit length adjuster is provided after the encoder, and performs bit length adjustment on the first bit sequence such that the second bit sequence has a bit length that is a multiple of X+Y, and outputs the first bit sequence after the bit length adjustment as the second bit sequence. As a result, a problem between a codeword length of a block code and the number of bits necessary to perform mapping by a set of modulation schemes is solved.

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: 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: 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: One coding scheme is selected from a plurality of coding schemes, an information sequence is encoded by using the selected coding scheme, and an obtained encoded sequence is modulated to obtain a modulated signal. The obtained modulated signal is subjected to a phase change and is transmitted. The plurality of coding schemes include at least a first coding scheme and a second coding scheme. The first coding scheme is a coding scheme with a first coding rate for forming a generated first codeword as a first encoded sequence by using a first parity check matrix. The second coding scheme is a coding scheme with a second coding rate obtained after puncturing processing, for generating a second encoded sequence by performing the puncturing processing on a generated second codeword by using a second parity check matrix different from the first parity check matrix. The number of bits of the first encoded sequence is equal to the number of bits of the second encoded sequence.

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 method for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. Each signal has been modulated according to a different modulation sheme. The transmission method applies precoding on both signals using a fixed precoding matrix, applies different power change to each signal, 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 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 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 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.