Transmission method, transmission apparatus, reception method and reception apparatus
View Patent ↗All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.
1. A reception method comprising:
receiving first radio frequency subcarrier signals and second radio frequency subcarrier signals with one or more antennas;
converting the first radio frequency subcarrier signals to first baseband subcarrier signals and the second radio frequency subcarrier signals to second baseband subcarrier signals;
obtaining a first control information indicating a first modulation scheme and a first error correction encoding scheme from the first baseband subcarrier signals, and a second control information indicating a second modulation scheme and a second error correction encoding scheme from the second baseband subcarrier signals;
demodulating the first baseband subcarrier signals in accordance with the first modulation scheme to obtain a first encoded bit sequence and the second baseband subcarrier signals in accordance with the second modulation scheme to obtain a second encoded bit sequence;
decoding the first encoded bit sequence in accordance with the first error correction encoding scheme and the second encoded bit sequence in accordance with the second error correction encoding scheme, to obtain data including audio data; and
generating an audio signal from the audio data and outputting the audio signal to an output terminal, wherein
the first baseband subcarrier signals include first modulation symbols which are precoded by using a plurality of precoding matrices, while regularly hopping between the precoding matrices, the first modulation symbols being composed of an in-phase component and a quadrature component and being modulated in accordance with the first modulation scheme,
the second baseband subcarrier signals include second modulation symbols which are precoded by using one of a plurality of precoding matrices, the second modulation symbols being composed of an in-phase component and a quadrature component and being modulated in accordance with the second modulation scheme,
the first modulation symbols include two first symbols that are data symbols used to transmit data at a first time and a first subcarrier of the first radio frequency subcarrier signals, two second symbols that are data symbols used to transmit data at a first time and a second subcarrier of the first radio frequency subcarrier signals, and two third symbols that are data symbols used to transmit data at a first time and a third subcarrier of the first radio frequency subcarrier signals,
the first subcarrier being adjacent to the second subcarrier and the third subcarrier, and
the two first symbols being precoded with a different precoding matrix than each of the two second symbols and two third symbols.
2. A reception apparatus comprising:
one or more antennas for receiving first radio frequency subcarrier signals and second radio frequency subcarrier signals;
a radio frequency (RF) converter that converts the first radio frequency subcarrier signals to first baseband subcarrier signals and the second radio frequency subcarrier signals to second baseband subcarrier signals;
a control information decoder that obtaining a first control information indicating a first modulation scheme and a first error correction encoding scheme from the first baseband subcarrier signals, and a second control information indicating a second modulation scheme and a second error correction encoding scheme from the second baseband subcarrier signals;
a demodulator that demodulates the first baseband subcarrier signals in accordance with the first modulation scheme to obtain a first encoded bit sequence and the second baseband subcarrier signals in accordance with the second modulation scheme to obtain a second encoded bit sequence;
a decoder that decodes the first encoded bit sequence in accordance with the first error correction encoding scheme and the second encoded bit sequence in accordance with the second error correction encoding scheme, to obtain data including audio data; and
an audio decoder that generates an audio signal from the audio data and outputs the audio signal to an output terminal, wherein
the first baseband subcarrier signals include first modulation symbols which are precoded by using a plurality of precoding matrices, while regularly hopping between the precoding matrices, the first modulation symbols being composed of an in-phase component and a quadrature component and being modulated in accordance with the first modulation scheme,
the second baseband subcarrier signals include second modulation symbols which are precoded by using one of a plurality of precoding matrices, the second modulation symbols being composed of an in-phase component and a quadrature component and being modulated in accordance with the second modulation scheme,
the first modulation symbols include two first symbols that are data symbols used to transmit data at a first time and a first subcarrier of the first radio frequency subcarrier signals, two second symbols that are data symbols used to transmit data at a first time and a second subcarrier of the first radio frequency subcarrier signals, and two third symbols that are data symbols used to transmit data at a first time and a third subcarrier of the first radio frequency subcarrier signals,
the first subcarrier being adjacent to the second subcarrier and the third subcarrier, and
the two first symbols being precoded with a different precoding matrix than each of the two second symbols and two third symbols.