What does FMCW stand for and what is it used for?

• A. Frequency Modulated Continuous Wave radar used to measure distance
• B. Fixed Motion Communication Wireless
• C. Frequency Modulated Constant Wave system
• D. Fast Magnetic Communication Wireless

Answer: (A)

FMCW stands for Frequency Modulated Continuous Wave radar. It measures distance by transmitting a continuous signal whose frequency is swept over time (a chirp). The reflected signal from a target returns with a delay, and when you mix the received echo with a sample of the transmitted signal, you get a beat frequency that is proportional to the time delay, which corresponds to range. This method provides precise distance measurements with relatively low peak power and is commonly used in radar systems such as radar altimeters and automotive or aviation sensing. Other options describe wireless communication or non‑varying-wave concepts that aren’t used for obtaining range in radar in this way.