Topic: Electromagnetics
A broadside array operating at 100 cm wavelength consist of 4 half wave dipoles spaced 50 cm apart. Each element carries radio frequency current in the same phase and of magnitude 0.5 A. The radiated power will be _____ if the radiation resistance is 146 ohm.
- A. 146 W
- B. 73 W
- C. 36.5 W
- D. 18.25 W
Answer: A. 146 W
Explanation: $P_{rad}=n\times I_{rms}^{2}\times R = 4\times(\frac{1}{2})^{2}\times146=146~W$.