Recently the Unmanned Aircraft System (UAS) has become very popular due to its current and projected opportunities in diversified applications from surveillance to security to militry. The Federal Aviation Administration (FAA) has mandated for all UASs to be equipped with an Automatic Dependent Surveillance Broadcast (ADS-B) transmitter by 2020. ADS-B is a next generation aircraft communication system, operating with two frequencies, 978 MHZ and 1090 MHz, which will transmit the information of identification, and precise position of an airplane to the nearby airplanes and ground station. At present, the ADS-B transmitter is fabricated with hybrid integrated circuits (HICs) in three different modules: a Phase Locked Loop (PLL) module, an Up-converter (modulator) module and a Power Amplifier (PA) module [8-10] which makes the system very large in size and expensive. In this work, for the first time an ADS-B transmitter as a part of Universal Access Transceievr (UAT) and Universal Beacon Radio (UBR) has beeen developed in a fully integrated single chip using the Complementary Metal Oxide Semiconductor (CMOS) process which is capable of operating both at 978 MHz UAT and 1090 MHz Extended Squitter (ES) modes. The chip provides the modulated output power of 23 dBm which is sufficient for the UAS to operate below class-A airspace. If the UAS needs to operate above this range or needs to operate for a manned aircraft system, this single chip ADS-B transmitter can be interfaced to drive an off-chip high-power PA, and, thus, it will reduce the burden of the input power and the gain of the off-chip PA. The chip supports both single tone and modulated baseband signals. In addition, this chip is capable of operating a part of new datalinks (960 MHz to 1164 MHz) and DME bands for UAS.