How is Location of a Flight or Aircraft Tracked- (ADS-B Technology)

ADS-B  (Automatic Dependent Surveillance Broadcast) system is widely used globally for real-time tracking of flights. Currently around 60% of passenger aircrafts are equipped with ADS-B transponder. When in flight the aircraft gets its GPS location from the satellite in space. Then ADS-B transponder in the aircraft now transmits the GPS location details (and other information including speed, vertical speed, Skuawk signal etc.) to nearby aircrafts and receivers on land. ADS-B signal is received by the receiver and information is analyzed and sent to base stations (including live tracking systems, ATC).  

Further resources:

Live Flight Airoplane Tracking Website

Amidst the current controversy of disappearance of Malaysian Airline flight MH370 I was researching on how to track live stat for flights and I found two very useful resources. These websites are quite useful if you want to track the live position of someone’s flight you are waiting for. They also tell about some very useful and technical information about flight such as speed and altitude. Try these website yourself and be amazed.

Once you search for a flight with its Flight No. Planefinder tells you flight’s Registration no., Altitude, Speed, Route, Course, Squawk etc. It lays out the flights location on Google  map and shows nearby flights as well.
To search a plane on planefinder you need to know the flight no. Simply click on Map Option on top right of page and enter flight no.

Flightradar24. When you search Altitude, Vertical speed, Speed, Track, Latitude, Longitude, Radar, Squawk information is displayed along with flights’s real time map on Google map.