The transmitter is the unit of the fiber-optic communication system responsible for converting an electrical information signal into an optical one. The major components of a transmitter are an LED and a laser diode. However, EPCB will talk something about the radio frequency transmitter this time. A radio frequency transmitter module is a small PCB sub-assembly capable of transmitting a radio wave and modulating that wave to carry data. Transmitter modules are usually implemented alongside a micro controller which will provide data to the module which can be transmitted. Radio frequency transmitters are usually subject to regulatory requirements which dictate the maximum allowable transmitter power output, harmonics, and band edge requirements.