Chapter 14, Problem 14.17P

A rectangular horn antenna, $\text{17 cm}\times \text{24 cm}$ and operating at a frequency of 2400 MHZ, has an effective area of ${\text{200 cm}}^{\text{2}}$ . If the radiated power is 100 W, calculate the
(a) mean power density at the aperture,
(b) maximum power density in the near field,
(c) distance to the start of the far field,
(d) power density in the far field, at a distance of 5 m, and
(e) distance at which the power density is down to ${\text{1 mW/cm}}^{\text{2}}$ .