A signal conversion unit (120) of a signal transmission apparatus (10) includes an in-band distortion compensation analog circuit unit (122) that generates, for each band, an in-band distortion compensation signal for compensating for in-band intermodulation distortion occurring due to frequency mixing of RF signals of a single band, the distortion being included in RF signals which are output from an amplification unit (130), and causes the generated signal to be carried by the RF signals corresponding to the single band, and an inter-band distortion compensation analog circuit unit (124) that generates, for each combination of two bands, an inter-band distortion compensation signal for compensating for cross-modulation distortion occurring due to frequency mixing of RF signals between a plurality of bands which are input to the amplification unit (130), and causes the generated signal to be carried by each of the RF signals corresponding to the two bands.