Abstract: According to one embodiment, a wireless transmission method is disclosed. The method can perform feedback loop processing including subtracting a feedback data signal obtained by multiplying a feedback processing data signal by a gain from an input data signal to generate the feedback processing data signal. The method can perform beam forming processing with respect to the feedback processing data signal and at least one pilot signal for channel estimation to generate a beam-formed signal. In addition, the method can transmit the beam-formed signal by a plurality of antennas. Precoding processing performed on the pilot signal is only beam forming processing.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: A wireless communication apparatus includes a plurality of antennas, transmits a plurality of known symbol sequences each including a plurality of known symbols by using the antennas, each of the known symbols having subcarrier arrangement on which plural known information of the each of the known symbols are carried on, and inversion/non-inversion of a phase of known information on one of two adjacent subcarriers of the subcarrier arrangement being controlled in accordance with the number of the known symbols and time position of the each of the known symbols, and transmits data symbols by using the antennas after the known symbol sequences are transmitted.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: A wireless device, method, and signal for use in communication of a wireless packet between transmitting device and a wireless receiving device via a plurality of antennas, wherein a signal generator generates wireless packet including a short-preamble sequence used for a first automatic gain control (AGC), a first long-preamble sequence, a signal field used for conveying a length of the wireless packet, an AGC preamble sequence used for a second AGC to be performed after the first AGC, a second long-preamble sequence, and a data field conveying data. The AGC preamble sequence is transmitted in parallel by the plurality of antennas.

Abstract: A wireless device, method, and signal for use in communication of a wireless packet between transmitting device and a wireless receiving device via a plurality of antennas, wherein a signal generator generates wireless packet including a short-preamble sequence used for a first automatic gain control (AGC), a first long-preamble sequence, a signal field used for conveying a length of the wireless packet, an AGC preamble sequence used for a second AGC to be performed after the first AGC, a second long-preamble sequence, and a data field conveying data. The AGC preamble sequence is transmitted in parallel by the plurality of antennas.

Abstract: A wireless device, method, and signal for use in communication of a wireless packet between transmitting device and a wireless receiving device via a plurality of antennas, wherein a signal generator generates wireless packet including a short-preamble sequence used for a first automatic gain control (AGC), a first long-preamble sequence, a signal field used for conveying a length of the wireless packet, an AGC preamble sequence used for a second AGC to be performed after the first AGC, a second long-preamble sequence, and a data field conveying data. The AGC preamble sequence is transmitted in parallel by the plurality of antennas.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: A wireless device, method, and signal for use in communication of a wireless packet between transmitting device and a wireless receiving device via a plurality of antennas, wherein a signal generator generates wireless packet including a short-preamble sequence used for a first automatic gain control (AGC), a first long-preamble sequence, a signal field used for conveying a length of the wireless packet, an AGC preamble sequence used for a second AGC to be performed after the first AGC, a second long-preamble sequence, and a data field conveying data. The AGC preamble sequence is transmitted in parallel by the plurality of antennas.

Abstract: A wireless communication apparatus includes a first storage unit configured to store each of a plurality of upper limit values of absolute values of additional signals that are set for a corresponding one of a plurality of first wireless communication apparatuses and are added when a plurality of modulation symbols to be transmitted to the first wireless communication apparatuses are precoded, a coding unit configured to decide each of a plurality of first values of the additional signals for a corresponding one of the first wireless communication apparatuses within ranges defined by the upper limit values, and precode the modulation symbols using the first values to obtain a plurality of transmission signals, and a first transmission unit configured to transmit, using multi-user MIMO (Multiple Input Multiple Output), the transmission signals to the first wireless communication apparatuses.

Abstract: A wireless device, method, and signal for use in communication of a wireless packet between transmitting device and a wireless receiving device via a plurality of antennas, wherein a signal generator generates wireless packet including a short-preamble sequence used for a first automatic gain control (AGC), a first long-preamble sequence, a signal field used for conveying a length of the wireless packet, an AGC preamble sequence used for a second AGC to be performed after the first AGC, a second long-preamble sequence, and a data field conveying data. The AGC preamble sequence is transmitted in parallel by the plurality of antennas.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: A wireless device, method, and signal for use in communication of a wireless packet between transmitting device and a wireless receiving device via a plurality of antennas, wherein a signal generator generates wireless packet including a short-preamble sequence used for a first automatic gain control (AGC), a first long-preamble sequence, a signal field used for conveying a length of the wireless packet, an AGC preamble sequence used for a second AGC to be performed after the first AGC, a second long-preamble sequence, and a data field conveying data. The AGC preamble sequence is transmitted in parallel by the plurality of antennas.

Abstract: A wireless device, method, and signal for use in communication of a wireless packet between transmitting device and a wireless receiving device via a plurality of antennas, wherein a signal generator generates wireless packet including a short-preamble sequence used for a first automatic gain control (AGC), a first long-preamble sequence, a signal field used for conveying a length of the wireless packet, an AGC preamble sequence used for a second AGC to be performed after the first AGC, a second long-preamble sequence, and a data field conveying data. The AGC preamble sequence is transmitted in parallel by the plurality of antennas.

Abstract: A radio communication apparatus includes: generation units generating first to mth signals; a storage storing allocation information defining that beams of different quality levels are allocated to first to mth communication apparatuses for each of first to nth subcarriers so that frequencies of respective quality levels are substantially uniform over all the subcarriers among the apparatuses; determining units determining transmission weights by which the signals are multiplied so that the beams according to the allocation information are formed for the apparatuses for each of the subcarriers; generation units performing multiplication processing by using the signals and the weights for each of the subcarriers to generate first to hth weighted signals for each of the subcarriers; transform units performing inverse Fourier transform on the weighted signals for each of the subcarriers to generate first to hth transformed signals; and transmission processing units transmitting the transformed signals via first

Abstract: Before data is transmitted from a plurality of antennas, a plurality of known symbol sequences are transmitted from these antennas. Each known symbol sequence contains a plurality of known symbols having different subcarrier arrangements. Known symbols transmitted from different antennas have different subcarrier arrangements.

Abstract: In a wireless transmitting device which performs transmission by an OFDM using a plurality of subcarriers orthogonal to each other, a plurality of preambles to which a plurality of different subcarrier groups selected from a plurality of subcarriers within an OFDM signal band are allocated are transmitted by using a plurality of transmit antennas, and data is transmitted by using the antennas after the preambles are transmitted.

Abstract: A wireless transmission device which communicates with a wireless reception device is provided with a transmission-signal-generating unit configured to generate, transmission signals having transmission rates arranged in order corresponding to an input order of data items of the information sequence. The transmission device is also provided with a preamble adder which adds, to the transmission signals, respective preamble signals assigned in order of the transmission rates and used for estimation of channel responses at the wireless reception device. The transmission device is further provided with transmission units configured to transmit the transmission signals with the preamble signals added thereto.

Abstract: A wireless communication apparatus includes a plurality of antennas, transmits a plurality of known symbol sequences each including a plurality of known symbols by using the antennas, each of the known symbols having subcarrier arrangement on which plural known information of the each of the known symbols are carried on, and inversion/non-inversion of a phase of known information on one of two adjacent subcarriers of the subcarrier arrangement being controlled in accordance with the number of the known symbols and time position of the each of the known symbols, and transmits data symbols by using the antennas after the known symbol sequences are transmitted.

Abstract: A wireless communication system which transmits and receives a signal by using a plurality of wireless apparatuses, comprising: a first wireless apparatus group having a plurality of transmitting apparatuses, each transmitting a wireless signal based on a first control signal, said first wireless apparatus group forming a first ad-hoc network between said transmitting apparatuses; and a second wireless apparatus group having a plurality of destination apparatuses, each receiving the wireless signal transmitted from said first wireless apparatus group, said second wireless apparatus group transmitting and receiving the wireless signal received by said destination apparatuses based on a second control signal, and said second wireless apparatus group forming a second ad-hoc network between said destination apparatuses different from said first ad-hoc network.