23-09-2016, 11:57 AM
1455815979-WIRELESSCHARGINGOFMOBILESUSINGMICROWAVES.pdf (Size: 178.84 KB / Downloads: 7)
ABSTRACT
Mobile Phones are part of our life. It is the fastest and the easiest medium of
communication. Battery life of mobile phone is always been a problem for manufacturers.
People are complaining about their mobile’s battery life, that they don’t have long battery life
and they have to charge their phone several times. In this paper a new idea is shown to charge
your mobile phone anywhere you want without connecting its charger. This is done using
microwaves. Microwaves are the radio waves which provide communication between two
mobile phones. The microwave is sent with the message by the transmitter using antenna at the
frequency of 2.45GHz. Here we are using Microwaves as the source of energy to charge the
phone. We have to add a sensor, a rectenna circuit and a filer in our mobile phone to do the job.
By adding these things we can charge our phone using microwave when we talk. So as we talk
more we can charge more!!
INTRODUCTION
1.1 Electromagnetic Spectrum
As we know that when light shone through
the prism it is divided in all the colors which
we called rainbow, and technically it is
called visible spectrum. So light is made of
photons. Photons are bundle of energy.
Light is traveling at the speed of 3,00,000
km/hr So when light hit an object coming on
its way it actually rebound from its surface.
And it comes in to our eyes and we can see
the object. But color of the object is seen by
us is depend how much amount of energy is
rebound as photons from the object. But
some theory can’t be explained by taking the
light as the bunch of photos. So some
physicians assume that it is some kind of
wave. They define an electromagnetic
sanctum of different wave lengths which is
divided in two parts. One is electric field
and the other is magnetic field.
1.2 Microwave Region
Microwaves are the Radio wave which has
the wave length range of 1 cm to 1 meter.
And the frequency is 300MHz to
300GHz.Each and every object on the earth
absorb different amount of microwave
energy. Microwave oven converts this
microwave energy in to the frequency which
the food absorbs and gets energy from it and
get worm. But the bowl containing the food
do not get worm because its capacity of
absorbing microwave frequency is different!
Microwaves are good at carrying
information from one place to other. As the
microwave penetrates the solid material and
also it do not have and effect of weather and
rain etc. So it is useful to carry information.
2. WIRELESS POWER TRASMISSION
Nikolas Tesla is the father of wireless
electricity transmission. Who first
transmitted electricity without wire.
Magnetic induction is the main principle
behind the wireless power transmission. As
we put one coil carrying current through it,
it creates a magnetic field near to it. And if
we put other coil over there than it is induce
by the first coil and it carry current from it!
This is the simple principle behind it.
2.1 Wireless Power Transmission System
William C. Brown demonstrated how power
can be transfer through space using
microwaves. The concept of wireless power
transmission is shown the block diagram.
Here as we can see there are two part. One is
transmitting part and the other is the
Receiving part. At the transmitting end there
is one microwave power source which is
actually producing microwaves. Which is
attach to the Coax-Waveguide and here
Tuner is the one which match the impedance
of the transmitting antenna and the
microwave source. Directional Coupler
helps the signal to propagate in a particular
direction. It spread the Microwaves in a
space and sent it to the receiver side.
Receiver side Impedance matching circuit
receives the microwave signal through
Recteena circuit. This circuit is nothing but
the combination of filter circuit and the
schottky Diode. Which actually convert our
microwave in to the DC power!
2.2 Components of wireless power
transmission system
The important components of this system
are Microwave generator, Transmitting
antenna, and the receiving antenna.
Microwave Generator
The Microwave Generator is the one which
generates the microwave of preferred
frequency. It generates the Microwave by
the interaction of steam of elections and the
magnetic field.
2.2.2 Transmitting Antenna
There are many kind of slotted wave guide
antenna available. Like parabolic dish
antenna, microstrip patch antenna are the
popular type of transmitting antenna.
2.2.3 Rectenna
A rectenna is a rectifying antenna, a
special type of antenna that is used to
convert microwave energy into direct
current electricity. A simple rectenna
element consists of a dipole antenna with an
RF diode connected across the dipole
elements. The current included by the
microwaves in the antenna is rectified by the
diode. Which powers a load connected
across the diode. Schottky diodes are used because they have low voltage drop and
high speed so that they have low power loss.
. DESIGN
3.1 Transmitter design
A magnetron is a diode vacuum tube.
Filament in the tube act as the cathode.
Magnetron is actually act as a oscillator to
produce microwaves. It can be done by
putting magnet between the resonating
chambers which is the center of the
oscillator. These resonating chambers are
called the anode of the magnetron. When
electrons come out from the cathode it direct
towards the Anode. As it pass through the
magnetic field it start circulating in the
resonating cavity and start producing waves
according to its frequency. And the
generated RF signal flow outside of the
chamber.
CONCLUSION
So here it is shown that a mobile phone can
be charge using the microwave which we
get everywhere where a mobile phone can
perform its task