What is the meaning of Exciter?

A person who excites.

The electronic oscillator that generates the carrier signal for a transmitter.

An audio signal processing technique used to enhance a signal by dynamic equalization, phase manipulation, harmonic synthesis of (usually) high frequency signals, and through the addition of subtle harmonic distortion.

to excite (to stir the emotions of)

first-person singular present passive subjunctive of excitō

Source: wiktionary.org