Frequently Asked Questions On Antenna Theory With Answers -19.


This page contains basic questions and short notes on some of the keywords on antenna theory:


91) Define Refractive index?

It is defined as n = c / Vp
where n = √εr


92)Define maximum Usable Frequency?

The maximum Frequency that can be reflected back for a given distance of transmission is called the maximum usable frequency (MUF) for that distance.

MUF = fcr sec φi


93) Define skip distance?

The distance with in which a signal of given frequency fails to be reflected back is the skip distance for that frequency. The higher the frequency the greater the skip distance.


94) Define Optimum frequency?

Optimum frequency for transmitting between any two points is therefore selected as some frequency lying between about 50 and 85 percent of the predicted maximum usable frequency between those points.


95) What is wave impedance?

η = ηo / √ 1 - (fc - f)

η = 377 / √ 1 - (fc - f)

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