(1)Reflection coefficient (2) Standing wave ratio
(1)Reflection coefficient
Reflection coefficient R=Er/Ei
=3/6
R=0.5
(2) Standing wave ratio
SWR=Ei+Er/Ei-Er
=6+3/6-3
SWR =3
Description : For a transmission line, the incident voltage. Ei = 6V and Er =2V ,Calculate: (i) Reflection Coefficient (ii) SWR
Last Answer : Reflection Coefficient(K) = Er / Ei = 2V / 6V K = 0.333 SWR = 1+K / 1- K = 1+0.333 / 1-0.333 = 1.333 / 0.667 SWR= 1.998
Description : a) For a transmission line, Find SWR and reflection coefficient R if, i. There is no reflected voltage. ii. Reflected voltage and incident voltage is equal. iii. If reflected voltage=20V and incident voltage=10V. iv. If reflected voltage=10V and incident voltage =20V.
Last Answer : reflection coefficient R=Vr/Vi i. There is no reflected voltage. i.e,Vr=0 R=0 SWR= 1+R/1-R=1 ii. Reflected voltage and incident voltage is equal. Vr=Vi; R=1 SWR= 1+R/1-R=1+1/1-1=infinity iii. If reflected ... and incident voltage =20V. Vr=10 and Vi=20 R=10/20=0.5 SWR= 1+R/1-R=1+.5/1-.5=3
Description : Define standing wave ratio.
Last Answer : Standing wave ratio is defined as the ratio of maximum voltage (Vmax) to minimum voltage (Vmin). Standing wave ratio is also defined as the ratio of maximum current (Imax) to minimum current (Imin).
Description : If Voltage Standing Wave Ratio, (VSWR) of a wave is 2, its reflection coefficient will be _____.
Last Answer : If Voltage Standing Wave Ratio, (VSWR) of a wave is 2, its reflection coefficient will be 1/3.
Description : Calculate the characteristics impedance for a transmission line having L=0.5 mH/Km, C=0.08 µF and negligible R and G.
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Last Answer : Solution :
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Last Answer : b) 0.4
Last Answer : Whenever a wave is incident on a perfect conductor then the reflection coefficient is 0.
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Description : Define VSWR with refernce to standing waves.
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Description : Draw general equivalent circuit of transmission line.
Last Answer : Fig. General Equivalent circuit of transmission line
Description : State and explain the losses in transmission line.
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Last Answer : Define critical frequency w.r. to wave propagation.
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Description : How quarter wave transformer is used for impedance matching.
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Description : Describe the term virtual height with the help of diagram showing ionized layer and the path of wave.
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Description : Compare ground wave and space wave propagation on the basis of: (i) Frequency range (ii) Method of propagation.
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Description : Describe the effect of ionosphere on sky wave propagation.
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Description : List and explain the properties of quarter wave transformer.
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Description : Draw and label the circuit diagram of ratio detector
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Description : A 50Ω transmission line is terminated in an impedance of 20-j50. What will be the reflection coefficient? A) 0.69 B) 1.69 C) 6.9 D) 16.9
Last Answer : A 50Ω transmission line is terminated in an impedance of 20-j50. What will be the reflection coefficient? A) 0.69 B) 1.69 C) 6.9 D) 16.9
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Description : Describe line of sight propagation in brief.
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