Define waves and transmission lines, Electrical Engineering

Assignment Help:

Q. Define waves and transmission lines?

In basic circuit theory we neglect the effects of the finite time of transit of changes in current and voltage and the finite distances over which these changes occur. We assume that changes occur simultaneously at all points in the circuits. But there are situations in which we must consider the finite time it takes for an electrical or magnetic wave to travel and the distance it will travel. It is in these situations that one must employ traveling-wave theory. Traveling-wave concepts must be used whenever the distance is so great or the frequency so high that it takes an appreciable portion of a cycle for the wave to travel the distance.

For sinusoidal signals, a wavelength λ is defined as the distance that a wave travels in one cycle or period. Since electric waves in free space travel at the velocity of light c(≅ 3×108 m/s), the free-space wavelength is given by c/f. Table shows some free-space wavelengths at selected frequencies. If the traveling-wave technique is to be employed for distances greater than 1/10 wavelength, a distance of 3 mm at 10 GHz would require the use of this technique, whereas the same distance at 100 MHz would not. On the other hand, a distance of 1 km is insignificant at power-line frequencies, but not in the broadcast band.

2161_Define waves and transmission lines.png

The connection of the high-power output of a transmitter located on a building to the transmitting antenna on a tower is often made by special conductors called transmission lines, which guide thewaves and usually consist of two ormore parallel conductors,which are separated  by insulating (dielectric) materials.While transmission lines are available in many forms, Figure illustrates cross sections of some common types. The two-wire line of Figure (a) isused to connect some television antennas. The coaxial cable of Figure (b) is themost widely used of the many possible cable-type transmission lines. For printed-circuit and integrated-circuit applications, transmission lines sketched in Figures (c) through (f) are commonly employed.

513_Define waves and transmission lines1.png

 


Related Discussions:- Define waves and transmission lines

Digital logic design, how to sort three number in descending order and disp...

how to sort three number in descending order and display on seven segment

How monitoring and control has be done, How control and monitoring has be d...

How control and monitoring has be done - Sensors gather information from application being monitored or controlled. - The data being gathered is frequently analogue in natur

Moving coil transducers, Note transducers  convert a physical quantity from...

Note transducers  convert a physical quantity from one  form to another.  The case below illustrates a typical moving coil meter   that   converts   a   current into a mechanical a

Determine the regulation of three-phase, A three-phase, six-pole, wye-conne...

A three-phase, six-pole, wye-connected synchronous generator is rated at 550 V and has a synchronous reactance Xs = 2 . When the generator supplies 50 kVA at rated voltage and a p

Working of a negative clamping circuit, Q. Draw and explain the working of ...

Q. Draw and explain the working of a negative clamping circuit. The clamping network shown above is a negative clamping circuit that will clamp the input signal to a negative d

Dual trace and dual beam cro, what is difference between dual trace and dua...

what is difference between dual trace and dual beam cro?

find the maximum power transferred and input resistance, Given: R 1 = R 3...

Given: R 1 = R 3 = 1 k_, R 2 = 100 k_ and k = 0.1 A/V, and step-up transformer turns ratio is 10. a) Find the value of the load resistor RL that would maximize the power

EDC, What is hall effect?

What is hall effect?

Electrical starter motor, ELECTRICAL STARTER MOTOR This usually consist...

ELECTRICAL STARTER MOTOR This usually consists of a heavy duty, compound wound, DC motor, which draws its electrical supply from an external source. The motor works in conjunc

Components of gis - methods, Methods: A successful GIS operates accordi...

Methods: A successful GIS operates according to a well-designed plan and business rules that are the models and operating practices unique to every organization. GIS gives i

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd