Question

The wavelength of the EM signal propagation in the T.I.L for duct propagation is _________

(a) \(λ=2.5h_d \sqrt{∆μ×10^{-6}} \)

(b) \(λ=2.5h_d \sqrt{∆μ×10^6} \)

(c) \(λ=5.2h_d \sqrt{∆μ×10^{-6}} \)

(d) \(λ=25h_d \sqrt{∆μ×10^{-6}} \)

I had been asked this question in a job interview.

My question is from Space Wave Propagation in portion Space Wave Propagation of Antennas

Answer 1

The correct choice is (a) \(λ=2.5h_d \sqrt{∆μ×10^{-6}} \)

To elaborate: The wavelength of the EM signal propagation in the T.I.L for duct propagation is

\(λ=2.5h_d \sqrt{∆μ×10^{-6}} \)

Here ∆μ is change in the refraction index in height hd.