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SEMESTER PROJECT

Submitted by

Syed faraz ahmed (ee-2008-093)

Yousuf khan (ee-2008-75)Ahmed hussain (ee-2008-117)

Mateen iftikhar(ee-2008-065)

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Microwave radiationare the radiating wave

movements in whichmicrowave energytravels. Thewavelengths can befrom as long as one

meter to as short as onemillimeter. Microwaveshave a frequency rangeof 0.3 Ghz to 300 Ghz.

They are found betweenthe radio waves and theinfrared waves in theelectromagnetic spect

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Microwaves take a straight linepath. They can pass through non-metal materials such as plastic

and glass, but get reflected offmetal surfaces. Microwaves are absorbed by

materials that have a high watercontent and produce heat, someexamples are food, fruits,vegetables etc. This is where themicrowave kitchen appliances

work, the microwave oven (in thepicture) is used for heating upour food by microwaves.

What are microwaves?

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A microwave ovenconsists: a high voltagetransformer, an electrontube called magnetron , awave guide fan and a

oven chamber. Thetransformer passes electricenergy to the magnetronand the magnetronconverts this electricenergy into microwave

radiation. The microwavesare reflected in the ovenchamber and are absorbedby the food

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The microwaveabsorption, happenswhen the watermolecules in the food

begin to vibrate. Thismolecular movementproduces heat and theresultant heat cooks the

food. Foods that havehigher concentrations ofwater molecules cookfaster.

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OUTLINES

WHAT IS

MICROWAVE

RADIATION?

HOW

MICROWAVE

OVEN WORKING?

WHAT TECHNICAL DESIGN OF

MICROWAVE ? 

HOW DOES

MICROWAVE

COOKING? 

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Microwave radiation is

part of the

electromagnetic radiation

with a wavelength of 

long-term in “cm”

measured from 0.3 to 30

centimeter produces

these rays in nature when

passing electric

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Microwave oven usesmicrowave radiation toheat food in the subjectinside the oven

microwave radiation areradio waves withfrequencies 2500 MHz

and the radio waves atthis frequency has animportant property

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The microwave oven cookfood from the inside tooutside

Absorbs water and fat and

sugar molecules, consistingof food, radio waves

Temperature of foodparticles at the same timeand at the same temperaturebecause all the particles areraised at the same time is nottransmitted to the heatconduction 

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The food particles that containwater, fats and sugars absorbmicrowave radiation through atomsand molecules of food andabsorption of this radiation givesenergy make the move significantlyand collide and produce heat for 

heating cooking

That the material, plastic and glass,ceramics and pottery does notabsorb microwave radiation and isnot affected, and this means thatthey will not rise the temperature,and the shiny metallic materials suchas aluminum that reflects the rays istherefore prohibited for use withinmicrowave ovens

 

Depends artistic design of the oven onoverlapping combinations of electricalcircuits and mechanical devices for theproduction and organization of theenergy needed for heating and cooking,

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  Navigation

Global Navigation Satellite

Systems (GNSS) including the American Global Positioning System (GPS) and the Russian GLONASS broadcast navigational signals in various bandsbetween about 1.2 GHz and 1.6 GHz. 

 Power   A microwave oven  passes (non-ionizing)

microwave radiation (at a frequency near  2.45 GHz) through food,causing  dielectric heating  by absorptionof energy in the water, fats, and sugar contained in the food. 

 Microwave heating is used in industrial

 processes for drying and curing products.   Microwaves can be used to transmit 

 power  over long distances 

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An antenna is a device that:

(or aerial) is an electrical devicewhich converts electriccurrents into radio waves , and viceversa.It is usually used with a radio

transmitter or radio receiver . 

Any conductor throughwhich an RF current isflowing, can be an antenna.

Any conductor that canintercept an RF field can bean antenna.

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 Typically an antenna consists of an arrangement of metallic conductors ("elements"), electrically

connected (often through a transmission line ) to thereceiver or transmitter. The first antennas were built in 1888 by German

 physicist Heinrich Hertz in his pioneeringexperiments to prove the existence of electromagneticwaves predicted by the theory of  James Clerk

 Maxwell.

A good antenna works

A bad antenna is a waste of time & money

Antenna systems can be very inexpensive andsimple

They can also be very, very expensive

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Directivity or Gain: 

Is the ratio of the power radiated by an antenna in its direction of maximum radiation to thepower radiated by a reference antenna in the same direction.Is measured in dBi (dB referenced to an isotropic antenna) or dBd (dB referenced to a half

wavelength dipole)

Feed point impedance ( also called input or drive impedance):Is the impedance measured at the input to the antenna.The real part of this impedance is the sum of the radiation and loss resistancesThe imaginary part of this impedance represents power temporarily stored by the antenna.

Bandwidth:

Is the range of frequencies over which one or more antenna parameters stay within a certainrange.

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 Isotropic antenna or isotropic radiator is ahypothetical (notphysically realizable)concept, used as a useful

reference to describe realantennas.

Isotropic antenna radiatesequally in all directions.

Its radiation pattern isrepresented by a spherewhose center coincideswith the location of theisotropic radiator.

Directional antenna  Directional antenna is anantenna, which radiates(or receives) much morepower in (or from) some

directions than in (orfrom) others.

Note: Usually, this term isapplied to antennas whosedirectivity is much higher

than that of a half-wavelength dipole.

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An antenna, whichhas a non-directionalpattern in a plane

It is usuallydirectional in otherplanes

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Wire Antennas

Short Dipole Antenna 

Dipole Antenna Half-Wave Dipole 

Broadband Dipoles 

Monopole Antenna 

Folded Dipole Antenna Small Loop Antenna 

Microstrip Antennas

Rectangular Microstrip

(Patch) Antennas Planar Inverted-F

Antennas (PIFA) 

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CornerReflectorParabolicReflector (DishAntenna) 

Travelling WaveAntennas

Helical

AntennasYagi-UdaAntennas Spiral Antennas 

Aperture Antennas

Slot AntennaCavity-Backed Slot Antenna 

Inverted-F Antenna Slotted WaveguideAntenna Horn Antenna 

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