OFDM transmitter device having a symbol generator for generating non-zero control symbols, and OFDM transmission method including generating non-zero control symbols

摘要

An OFDM transmitter and an OFDM receiver respectively transmit and receive N (N≧2, N is an integer) control symbols. For each control symbol, a guard interval time-domain signal is, for example, identical to a signal obtained by frequency-shifting at least a portion of a useful symbol time-domain signal by an amount different from any other symbol, or to a signal obtained by frequency-shifting one or both of a portion and a span of a useful symbol interval time-domain signal different from any other symbol by a predetermined amount.

主权项

1. An OFDM transmitter, comprising:
a first symbol generator generating a first control symbol and a second control symbol each being made up of a useful interval, a leading guard interval that precedes the useful interval, and a trailing guard interval that follows the useful interval, the leading guard interval of the first control symbol including a first leading signal in which a leading portion of the useful interval of the first control symbol has undergone a first frequency shift that is non-zero, the trailing guard interval of the first control symbol including a first trailing signal in which a trailing portion of the useful interval of the first control symbol has undergone the first frequency shift, the leading guard interval of the second control symbol including a second leading signal in which a leading portion of the useful interval of the second control symbol has undergone a second frequency shift that is non-zero, the trailing guard interval of the second control symbol including a second trailing signal in which a trailing portion of the useful interval of the second control symbol has undergone the second frequency shift, the leading guard interval of the first control symbol and the leading guard interval of the second control symbol differing in length, the trailing guard interval of the first control symbol and the trailing guard interval of the second control symbol differing in length, and total length of the leading guard interval of the first control symbol and the trailing guard interval of the first control symbol being equal to total length of the leading guard interval of the second control symbol and the trailing guard interval of the second control symbol; a second symbol generator generating a plurality of symbols different from the first control symbol and the second control symbol; and a symbol inserter inserting the first control symbol and the second control symbol into the plurality of symbols.