Transmission method, transmitter apparatus, reception method and receiver apparatus
View Patent ↗Transmission quality is improved in an environment in which direct waves dominate in a transmission method for transmitting a plurality of modulated signals from a plurality of antennas at the same time. 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 a signal in which a first symbol sequence and a second symbol sequence are multiplexed, the first symbol sequence and the second symbol sequence each including video information and each being a precoded signal transmitted from a different transmission system;
decoding information regarding a modulation scheme and information regarding an error correction scheme that are included in the received signal;
demodulating the received signal based on the decoded information regarding the modulation scheme to generate a demodulation symbol sequence; and
performing error-correction decoding on the demodulation symbol sequence based on the decoded information regarding the error correction scheme to output a data sequence including video information, wherein
the first symbol sequence and the second symbol sequence are each generated by applying a precoding matrix to a modulation symbol sequence, the precoding matrix being regularly switched between a plurality of precoding matrices for precoding, the modulation symbol sequence being generated by using a modulation scheme indicated by the decoded information regarding the modulation scheme,
a first symbol included in the first symbol sequence is transmitted at a first frequency,
a third symbol included in the first symbol sequence is transmitted at a third frequency adjacent to the first frequency in a frequency domain,
a second symbol included in the second symbol sequence is transmitted at a second frequency,
a fourth symbol included in the second symbol sequence is transmitted at a fourth frequency adjacent to the second frequency in the frequency domain, and
in the case where the third transmission symbol is a data symbol,
the first transmission symbol and the third transmission symbol are each generated by using a different precoding matrix, and
when any two of the first transmission symbol, the second transmission symbol, the third transmission symbol, and the fourth transmission symbol are transmitted at the same frequency, the same precoding matrix is used for generating the two transmission symbols.
2. A reception device comprising:
a receiver receiving a signal in which a first symbol sequence and a second symbol sequence are multiplexed, the first symbol sequence and the second symbol sequence each including video information and each being a precoded signal transmitted from a different transmission system;
a control information decoder decoding information regarding a modulation scheme and information regarding an error correction scheme that are included in the received signal;
a demodulator demodulating the received signal based on the decoded information regarding the modulation scheme to generate a demodulation symbol sequence; and
a decoder performing error-correction decoding on the demodulation symbol sequence based on the decoded information regarding the error correction scheme to output a data sequence including video information, wherein
the first symbol sequence and the second symbol sequence are each generated by applying a precoding matrix to a modulation symbol sequence, the precoding matrix being regularly switched between a plurality of precoding matrices for precoding, the modulation symbol sequence being generated by using a modulation scheme indicated by the decoded information regarding the modulation scheme,
a first symbol included in the first symbol sequence is transmitted at a first frequency,
a third symbol included in the first symbol sequence is transmitted at a third frequency adjacent to the first frequency in a frequency domain,
a second symbol included in the second symbol sequence is transmitted at a second frequency,
a fourth symbol included in the second symbol sequence is transmitted at a fourth frequency adjacent to the second frequency in the frequency domain, and
in the case where the third transmission symbol is a data symbol,
the first transmission symbol and the third transmission symbol are each generated by using a different precoding matrix, and
when any two of the first transmission symbol, the second transmission symbol, the third transmission symbol, and the fourth transmission symbol are transmitted at the same frequency, the same precoding matrix is used for generating the two transmission symbols.