Topic: Radar and Navigation
If range of a radar is to be doubled, the peak transmit power of the radar has to be
- A. increased by a factor of 2
- B. increased by a factor of 4
- C. decreased by a factor of 4
- D. increased by a factor of 16
Answer: D. increased by a factor of 16
Explanation: The maximum radar range is given by the Radar Equation: $R_{\text{max}} = \left[\frac{P_{t}G\sigma A_{e}}{(4\pi)^{2}S_{\text{min}}}\right]^{1/4}$.
From this, $R_{\text{max}} \propto [P_{t}]^{1/4}$.
So, if the range of a radar is to be doubled ($2R_{\text{max}}$), the peak transmit power of the radar has to be increased by a factor of $2^4 = 16$.