What will be the reflection coefficient of the wave of the load connected to the transmission line if surge impedance of the line is equal to load?

What will be the reflection coefficient of the wave of the load connected to the transmission line if surge impedance of the line is equal to load?

SOLUTION

The ratio of the reflected wave to the incident wave is known as the reflection coefficient and is simply a measure of the quality of the match between the transmission line and the terminating impedances.

In the general case, the amplitude of the wave reflected at the end of the transmission line is determined by the reflection coefficient, ρ (rho). The value of ρ depends on ZO and Zterms the termination impedance that appears at the end of the line:

ρ = Reflection coefficient = (Zterms − ZO) ⁄ (Zterms + ZO)

When a voltage wave with amplitude Vwave hits the end of a transmission line the wave with amplitude ρ · Vwave is reflected. Note that three simple cases match

Zterms = ZO :- When a transmission line is terminated in its characteristic impedance, the reflection coefficient is 0.

Zterms = 0:- The reflection coefficient of a short-circuited line is -1, producing a reflection of equal magnitude and opposite polarity.

Zterms = ∞ :– The reflection coefficient of an open-circuited line is +1, producing a reflection of equal magnitude and the same Polarity.

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