What is a key disadvantage of continuous wave radar?

Continuous wave radar operates by emitting a constant frequency signal and measuring the frequency shift of the returned signal, often used for speed detection. However, one of its critical limitations is its inability to measure the range or distance of an object. Since the radar continuously transmits a wave without interruption, it cannot determine the time delay between the transmission and reception of the signal, which is essential for calculating distance. This is distinct from pulse radar systems, which send bursts of energy and measure the time taken for the echo to return, enabling range calculation. The other options, while relevant to radar technology, do not accurately represent a fundamental limitation of continuous wave radar in the context of range measurement.