Abstract:
An indicator in a master AP from among a plurality of APs obtains communication quality of communication with an AP which is a communication partner. In the case where the obtained communication quality is less than a threshold, the indicator causes the plurality of APs including the master AP to perform cooperative operation to transmit data. In the case where the obtained communication quality is not less than the threshold, the indicator causes the plurality of APs including the master AP to stop the cooperative operation.
Abstract:
An encoder outputs a first bit sequence having N bits. A mapper generates a first complex signal s 1 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:
A transmission method of 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. One of signal generation processing in which phase change is performed and signal generation processing in which phase change is not performed is selectable, thereby improving general versatility in signal generation.
Abstract:
A first transmission signal z 1 (t) and a second transmission signal z 2 (t) are generated from a first modulated signal s 1 (t) and a second modulated signal s 2 (t) by using a precoding matrix, and parameters of the precoding matrix are calculated from feedback information.
Abstract:
By a transmission method according to one aspect of the present disclosure, in a broadcasting system that generates a first broadcasting signal and a second broadcasting signal by performing multi-antenna encoding on program data, and wirelessly transmits a first broadcasting signal and a second broadcasting signal, a first transmit station transmits the first broadcasting signal, a second transmit station transmits the second broadcasting signal, the first transmit station and the second transmit station transmit the first broadcasting signal and the second broadcasting signal to an overlapping area at an identical time using an overlapping frequency band, polarized wave transmitted from the first transmit station differs from polarized wave transmitted from the second transmit station, and arrangement of the first transmit station differs from arrangement of the second transmit station.
Abstract:
In a transmission method according to one aspect of the present disclosure, quality of received data can be improved in a reception device, when a probability of increasing a minimum Euclid at a signal point in an in-phase I-orthogonal Q plane during reception is increased in a radio wave propagation environment in which a direct wave is dominant. This enables provision of an MIMO (Multiple-Input Multiple-Output) system, which can improve the reception quality in an LOS environment while a plurality of transmit antennas and a plurality of receive antennas are used.
Abstract:
An orthogonal transform subunit 14 separates a reception signal into carriers on a per-symbol basis. In a channel characteristics estimation subunit 15, (i) an SP channel characteristics estimation part 20 calculates channel characteristics at carriers to which SPs are allocated, by using signals output from the orthogonal transform subunit 14, (ii) a symbol direction interpolation part 30 interpolates, in the symbol (time) direction, signals output from the SP channel characteristics estimation part 20, (iii) a TMCC channel characteristics estimation part 40 calculates channel characteristics at carriers to which TMCCs are allocated, by using signals output from the orthogonal transfer subunit 14, and (iv) an adaptive interpolation part 50 calculates filter coefficients by using signals output from the symbol direction interpolation part 30 and the TMCC channel characteristics estimation part 40, and adaptively interpolates signals output from the symbol direction interpolation part 30 by using values of the calculated filter coefficients.
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:
Provided is control information related to polarizations of antennas for MISO communication. The control signal generator generates polarization information indicating whether antennas used for transmission by MISO have only a first polarization or have a second polarization as well as the first polarization. With this structure, the present invention allows for the use of combinations of SISO, MISO and MIMO, taking the polarization of antennas. Furthermore, the present invention enables the receiver to reduce the power consumption.