Use a low frequency radar system
The first thing that you should do is employ a multistatic low-frequency radar system with numerous receivers and transmitters. Note that you should use multiple receivers and transmitters for this purpose, as this will increase your chances of detecting a plane that is flying in stealth mode. In order to detect a plane, you should also take help from advanced algorithms and attempt to trace FM radio signals, TV signals or mobile signals, if any.
Detect the aircraft while it deploys weapons
If it has become harder for you to detect the aircraft through means of algorithms and signals, then you must try to detect it while it deploys its weapons. In order to deploy its weapons and aim at the target, the aircraft has to use a radar system and this is the most vulnerable time for any aircraft. Therefore, it is strongly advised that you should focus and try to run the detection while it deploys its weapons.
Use the heat trail system
Regardless of the technology that could be used by any aircraft, there is little chance that it can get rid of its heat trials. Thus, it is strongly suggested that you should try to trace its heat system.
Use Doppler radar
If your normal radar is not working properly, then you must use a Doppler radar; this is a high frequency radar and is relatively efficient when it comes to the detection of stealth mode aircrafts.
Trace disturbances in the Earth’s magnetic field
You should also try to trace the disturbances that are created by the aircraft in the Earth’s magnetic field.