Question

For an isotropic source, Radiation intensity will be _____ on θ and ______ on Φ.

(a) Dependent, independent

(b) Independent, independent

(c) Independent, dependent

(d) Dependent, dependent

I have been asked this question in homework.

This key question is from Isotropic Radiators in chapter Antenna Parameters of Antennas

Answer 1

Correct answer is (b) Independent, independent

To explain I would say: Due to symmetric distribution in isotropic source, there will be no θ, ф components. Only radial component will be present. \( P_{total \,rad}=∯ Usinθdθd∅=4πU (For \,θ: 0 \,to \,π, \phi: 0 \,to\, 2π).\)

∴ Radiation intensity \(U=\frac{P_{total \,rad}}{4π}\)