To provide a transmitter with digital amplitude modulation using a conventional inexpensive filter which is not required to have a steep characteristic, and improving a signal to noise ratio as well.

In this digital amplitude modulation transmitter, an A/D converter 11 performs A/D conversion of an input modulating signal HS on the basis of the frequency of a sampling signal, and applies amplitude modulation to a carrier signal CA by the A/D conversion signal. In this case, a sampling signal generator 12 generates a signal having a frequency 2F0 twice as high as the frequency F0 of the carrier signal CA from the carrier signal CA, and supplies the generated signal as the sampling signal SA to the A/D converter 11. Accordingly, since the generated spurious component has a frequency odd multiple of the carrier signal, the spurious component spreads to a wide band, a filter 16 prepared for each amplifier PA1-PA32 can be used in common even if its characteristic is not steep, the signal to noise ratio can be also improved, and the number of the filter parts is prevented from increasing as well.