An optical signal transmission apparatus comprising: a modulation unit (101-1, 101-2) which modulates a transmission signal; a training signal sequence generation unit which generates a training signal sequence; a signal multiplexing unit (102-1, 102-2) which appends the training signal sequence to the transmission signal; and an electro-optical conversion unit (103-1, 103-2) which converts a signal sequence obtained by appending the training signal sequence to the transmission signal into an optical signal and transmits the optical signal, wherein the training signal sequence generation unit generates the training signal sequence by generating a plurality of signal sequences which have power concentrated in a plurality of different frequency bands and subsequently modulating at least one of amplitudes and phases of the plurality of signal sequences, the training signal sequence generation unit comprising: a basic signal sequence generation unit which generates a specific frequency band signal in which a frequency component having higher power than the transmission signal is concentrated only at a specific frequency; a modulation sequence generation unit (1003-1, 1003-2, 1003-3, 1003-4) which generates a modulation sequence for modulating the frequency component based on estimation precision of a transmission path parameter and a performance deterioration factor in at least one of an analog device and a propagation path; and a multiplier (1002-1, 1002-2, 1002-3, 1002-4) which multiplies an output sequence of the basic signal sequence generation unit by an output sequence of the modulation sequence generation unit (1003-1, 1003-2, 1003-3, 1003-4), and the modulation sequence generation unit (1003-1, 1003-2, 1003-3, 1003-4) modulating at least one of the amplitudes and the phases so that a power component, that is present at the specific frequency of the specific frequency band signal and is higher than that of the transmission signal, is subjected to frequency spreading. a modulation unit (101-1, 101-2) which modulates a transmission signal; a training signal sequence generation unit which generates a training signal sequence; a signal multiplexing unit (102-1, 102-2) which appends the training signal sequence to the transmission signal; and an electro-optical conversion unit (103-1, 103-2) which converts a signal sequence obtained by appending the training signal sequence to the transmission signal into an optical signal and transmits the optical signal, wherein the training signal sequence generation unit generates the training signal sequence by generating a plurality of signal sequences which have power concentrated in a plurality of different frequency bands and subsequently modulating at least one of amplitudes and phases of the plurality of signal sequences, a basic signal sequence generation unit which generates a specific frequency band signal in which a frequency component having higher power than the transmission signal is concentrated only at a specific frequency; a modulation sequence generation unit (1003-1, 1003-2, 1003-3, 1003-4) which generates a modulation sequence for modulating the frequency component based on estimation precision of a transmission path parameter and a performance deterioration factor in at least one of an analog device and a propagation path; and a multiplier (1002-1, 1002-2, 1002-3, 1002-4) which multiplies an output sequence of the basic signal sequence generation unit by an output sequence of the modulation sequence generation unit (1003-1, 1003-2, 1003-3, 1003-4), and the modulation sequence generation unit (1003-1, 1003-2, 1003-3, 1003-4) modulating at least one of the amplitudes and the phases so that a power component, that is present at the specific frequency of the specific frequency band signal and is higher than that of the transmission signal, is subjected to frequency spreading. <EOS>