Radarspotting
Miscellaneous => Other Topics => Antennas => Topic started by: Doodlebug on March 31, 2016, 08:20:34 AM
Just out of interest.........
What is the power output of the ADS-B transmitter on aircraft, please?
Albert.
Extract taken from net.
The ES ADS-B message is a 120 bit transmission that contains the aircraft identification, position, velocity, and status. The message is broadcast with a period that ranges randomly between 0.4 and 0.6 seconds. This randomization function is designed to prevent aircraft from having synchronized transmissions on the same frequency, and thus obscuring each other's transmissions. Required transmitter power for the ADS-B signal varies with the aircraft category. For smaller aircraft, a minimum transmission power of 75 W is specified while larger aircraft require a minimum power of 125 W or 200 W with a maximum output power for all classes of 500 W [6]. Any aircraft that is capable of operating at altitudes greater than 15,000 ft (4570 m) above sea level (ASL), or with cruising speeds above 175 kts (324 km/h), are required to transmit at 125 W as a minimum [6]. Aircraft use a quarter-wave monopole antenna for ADS-B transmissions that transmit vertically polarized signals [6].
Hope this helps
Albert. http://www.avweb.com/news/avionics/183234-1.html
Thanks guys.
Albert