SIGINT is a very advanced means of information gathering that not only collects information from non-communication sources like Radars, imagery and many other forms, but also Communication intelligence (COMINT).
SIGINT can be very useful in high-power radio monitors, remote surveillance, satellite imagery, and radar systems to monitor and detect hostile and illegal activities before and while they unfold. Signal Intelligence provides vital information for a nation to help countries' civilian and military leaders to cope up with potential and emerging threats to their countries.