A shaped-wave application section inputs a first pulse signal
corresponding to transmission data output from a transmission data output
section, and applies, to a modulation and amplification section, a signal
wave corresponding to a second pulse signal such that the waveform of the
first pulse signal is shaped. The pulse signal applied to the base of the
transistor of the modulation and amplification section is
amplitude-modulated into an amplitude-modulated wave in which the
amplitude-modulated portion is strengthened, in accordance with the
signal wave corresponding to the second pulse signal applied to the
emitter thereof. The amplitude-modulated wave is supplied to an antenna
section including a resonance circuit via the collector thereof, and is
transmitted as an electromagnetic wave from the antenna section.