USE OF “WAVELENGTHS TOWARDS GENERATOR”(WTG) SCALE AND “WAVELENGTHS TOWARDS LOAD”(WTL) SCALE ON SMITH CHART

Let us first discuss USE OF “WAVELENGTHS TOWARDS GENERATOR”(WTG) SCALE AND “WAVELENGTHS TOWARDS LOAD”(WTL) SCALE ON SMITH CHART

The outermost scale around the perimeter of Smith chart is called the Wavelengths towards generator(WTG) scale.It has been constructed to denote movement on the transmission line toward the generator,in units of the wavelength,λ.Thus ,l is measured in wavelengths and one complete rotation corresponds to l=λ/2. Continue reading “USE OF “WAVELENGTHS TOWARDS GENERATOR”(WTG) SCALE AND “WAVELENGTHS TOWARDS LOAD”(WTL) SCALE ON SMITH CHART”

Relation Voltage Standing Wave Ratio and Reflection Coefficient

Last time I have discussed the standing wave ratio and voltage standing wave ratio. Today we will discuss the reflection coefficient and relation of voltage standing wave ratio with the reflection coefficient.

REFLECTION COEFFICIENT

Definition:- Reflection co-efficient is defined as the ratio of the reflected voltage to the incident voltage. Continue reading “Relation Voltage Standing Wave Ratio and Reflection Coefficient”

Standing wave and standing wave ratio

In this article, we will understand; what is standing wave, standing wave ratio (SWR), voltage standing wave ratio (VSWR) and current standing wave ratio (CSWR) in context of transmission line.

STANDING WAVES

When a transmission line is not correctly terminated ,the travelling wave at the receiving end is reflected completely or partially at the termination. The combination of incident and reflected waves give rise to standing waves of current and voltage along the line, with definite maxima and minima of current and voltage along transmission line. Continue reading “Standing wave and standing wave ratio”

Input impedance for quarter wave and half wave transmission line

  1. Input impedance Zi for quarter wave transmission line

A transmission line is said to be quarter wave transmission line when its length equals quarter wavelength.

That is                                             l=λ/4

Or                                                   l=(2n-1)λ/4 (odd multiple of λ/4)

Or                                                   βl=2π/λ * λ/4                                              [ β=2π/λ]

=π/2 Continue reading “Input impedance for quarter wave and half wave transmission line”

TRANSMISSION LINE AND ITS TYPES

TRANSMISSION LINES

Transmission lines are used to carry electromagnetic energy from one point to another . It means it transfer from one point to another. Generally it consists of two conductors. It is used to connect a source to a load. The source may be a transmitter or an electric generator and the load may be an antenna. Transmission lines are used for operational frequencies equal to or less than about 3GHz. Above 3GHz they will be replaced by waveguides. Continue reading “TRANSMISSION LINE AND ITS TYPES”