Radiation intensity pattern of antennas, Electrical Engineering

Assignment Help:

Q. Radiation intensity pattern of Antennas?

Antennas do not radiate power equally in all directions in space. The radiation intensity pattern describes the power intensity (which is power per unit solid angle, expressed in units of watts per steradian) in any spatial direction. Conceptually it is convenient to define an isotropic antenna as a lossless antenna that radiates its power uniformly in all directions. Although an isotropic antenna cannot be realized in practice, it serves as a reference for comparison with real antennas. The radiation intensity for such an antenna, with input power P, is a constant in any direction, given by P/4π. The power gain G of a realistic antenna is a measure of the maximum radiation intensity of the antenna as comparedwith the intensity thatwould result froman isotropic antenna, with the same power input. G is then expressed as

576_Radiation intensity pattern of Antennas.png

Referring to Figure when a power Pt /Lt is applied to the transmitting antenna, let us find the signal power Sr available to the receiver from the receiving antenna. An isotropic transmitting antenna would cause a radiation power density (power per unit area of a sphere) of

518_Radiation intensity pattern of Antennas1.png

For a practical antenna that has power gainGt and loss Lta relative to an isotropic antenna, Equation (15.1.19) would be modified as

1347_Radiation intensity pattern of Antennas2.png

We shall assume that the transmitting and receiving antennas (reciprocal elements) point directly toward each other, so that their gains are maximum. Letting Lch denote any losses incurred by the wave in the channel (medium), and Are be the effective area of the receiving antenna, the power that the receiving antenna is able to produce is given by

1031_Radiation intensity pattern of Antennas3.png

Accounting for the receiving antenna loss and receiving-path losses, a total system loss L can be defined as

1845_Radiation intensity pattern of Antennas4.png

Quite often, for simplicity, in the case of LOS radio transmission illustrated in Figure, the transmission loss for a path of length R is given by

2476_Radiation intensity pattern of Antennas5.png

1630_Radiation intensity pattern of Antennas6.png


Related Discussions:- Radiation intensity pattern of antennas

What is meant by interrupt, What is meant by interrupt? Interrupt is an...

What is meant by interrupt? Interrupt is an external signal that causes a microprocessor to jump to a particular subroutine.

Constant voltage from solar panel, circuit for the buck boost regulator con...

circuit for the buck boost regulator connected to a ic regulator , my voltae range is 5v to 24v?

Obtain an expression for the induced emf, Q. Consider a conducting loop of ...

Q. Consider a conducting loop of length l and width w, as shown in Figure, rotated about its axis (shown by the broken line) at a speed of ωm rad/s under the influence of a magneti

Bcd to excess 3 code converter, What are the industrial applications of the...

What are the industrial applications of the project bcd to excess 3 code converter?

Simple harmonic motion, what is the application of simple harmonic motion i...

what is the application of simple harmonic motion in electrical engineering?

Circuit theory, i want circuit theory relavant assingment sir please immed...

i want circuit theory relavant assingment sir please immediately

Explain register direct and indirect data addressing mode, Explain Register...

Explain Register Direct and Indirect data addressing mode (with examples) available in microprocessors. Register Direct Modes and Register Indirect Modes: Does not giv

Construction of a two stage rc coupled amplifier, Q. Describe the construct...

Q. Describe the construction of a two stage RC coupled amplifier with diagram. A cascaded arrangement of common-emitter transistor stages is shown above. The output Y1 of

Explain properties and application of aluminium, Explain properties and app...

Explain properties and application of Aluminium. Properties of Aluminium: 1) Pure aluminium in colour is silver white. 2) Aluminium is a ductile metal and can be put

Full wave bridge rectifier circuit , Construct a full wave bridge rectifier...

Construct a full wave bridge rectifier circuit and connect it to the transformer output. What is the Output Voltage and Frequency?

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