How does RADAR determine the distance to an object?

RADAR determines the distance to an object primarily by calculating the time delay between the transmission of a signal and its reception after being reflected off an object. When a RADAR system transmits a pulse of electromagnetic energy, it travels at the speed of light. Once the signal encounters an object, it reflects back to the RADAR receiver. By measuring how long it takes for the signal to return, the system can calculate the distance to the object using the formula:

Distance = (Speed of Light x Time Delay) / 2

The division by two accounts for the round trip of the signal—going to the object and coming back. This principle is foundational in RADAR technology and is what enables the effective gauging of distances in numerous applications, from aviation and maritime navigation to weather forecasting and military surveillance.

The other options, while related to different aspects of RADAR technology, do not directly pertain to the method used to calculate distance. For instance, measuring the width of the signal refers to bandwidth considerations rather than distance, estimating based on signal strength is more related to the object's size or reflectivity, and analyzing frequency shift pertains to Doppler effects that measure speed rather than distance.