discusses topics such as wifi, radar, cellular phones and MRI

2. 1. COVER PAGE
2. CONTENTS
3. ELECTROMAGNETIC EXPLAINATION OF RADIO WAVES
4. WIFI
5. PROPERTIES OF WIFI
6. MRI (magnetic resonance imagining)
7. RADAR
8. CELL PHONES AND WALKIES
9. THE END THOUGHT
10. BIBLIOGRAPHY

3. Radio waves as you can see in the diagram below are the
longest in wavelength and lowest in level of frequency (waves
per second) this is shown from the curvature on the diagram
Radio waves have managed to give visuals, audio and text based
communication. These sources of communication have a range of
20KHz to 100GHz with mediums such as TV being further up the
spectrum and AM Radio at the lower end

4.  Wifi transmits at a frequency of 2.4 or 5 GHz (gigahertz) which is way higher than
most radio broadcasters such as TV, Mobile Phones and Walkie Talkies for example.
The higher frequency results in more information to be carried across and received.
 Wifi allows multiple wireless devices to run through 1 router which is connected to
your computer usually through your house phone connection. WiFi is similar to Radio
and TV when carrying information, it uses binary in 1’s and 0’s which is then received
visa versa and then decoded. Standard Wireless Routers in homes have an average
coverage of 30 meters in all directions.
 For example, in most homes only one main computer is plugged into the router and
uses something called a Ethernet cable to get the wireless service. This allows
several devices such as; laptops, mobile phones and other portable devices with the
same capability to use the same connection without any cables attached, hence
wireless connection. This in conclusion is cost effective for users as they need only 1
transmitter instead of many and allowing for greater productivity also as you can move
from room to room without disconnecting, also travellers who often use laptops on
trains take advantage of the capability to get work done on the move.

5. Although great most of the time, the downside to this multiple source of
connectivity is that if many people try to use high bandwidth applications at the
same time the connection can suffer levels of interference in terms of
performance. Ultimately you can lose connection altogether for a period of time
if too many people are actively using it. Which in turn makes people angry as
hell when a 30 second video clip takes 5 minutes to load.

6. MRI machine are often used to explore the
human infrastructure. This is achieved by
using magnets and radio waves that
specifically pick up hydrogen molecules
alone. The waves travel through the human
body and set off reactions within cells that
give off radio signals.

7. THE PROCESS OF RADAR
For example, a radar gun used by police is simply a radio
transmitter and receiver. An amplifier is used to then intensify the
signal which is then sent out through an antenna. The waves
then bounce back (at the speed of light ) to the receiver which is
channelled through the antenna then converted back to an
electrical current . Radar in its simplest form is used to
detect the distance of objects by using concentrating
radio waves and waiting for an echo to reflect back. The
time of the returning echo calculates the distance.
USES OF RADAR
• Detecting planes on ground & air to guide landings.
• Police use it to monitor speed
• Space operations, tracking satellites and debris.
• Aiding the military in locating the enemy, land & sea.
• Tracking wind pressure, hurricanes etc.
Use of radar on speeding car
• Even entering supermarkets through automatic doors.

8. The cellular telephone system is a great system that divides a city into
sections of cells. This division of cells allows multiple reuse of extensive
frequencies which in turn allows millions of cell users to operate phones
Simultaneously.
A cell phone system operates on a full-duplex radio system which
transmits 2 different frequencies so the communication can take place
and make a 2 way conversation. Each cell is usually on average 110
square miles in all directions. The cellular approach means phone convo’s
can have an incredible range and allow people to be hundreds of miles
apart and keep the connection compared to a walkie talkie for example
that can only receive from a mile or 2 at the longest. Walkie Talkie work on
a half – duplex system..This means only 1 channel can be used but with
many users on 1 frequency. This means like we know, that only1 person
can talk at a time.
Although cellular phones have the advantage of shifting its frequency and
cell to get great coverage, thick walls or surfaces like bridges etc still can
lead to connection failure. This is something walkie talkies can do without
fail.

9.  http://computer.howstuffworks.com/wireless-network.htm
 http://en.wikipedia.org/wiki/Cellular_frequencies
 http://electronics.howstuffworks.com/cell-phone1.htm
 http://electronics.howstuffworks.com/cell-phone2.htm
 http://electronics.howstuffworks.com/cell-phone3.htm
 http://www.laptopsarena.com/wireless-connection-for-internet-on-pc-or-laptop/
 http://www.holytaco.com/how-to-fix-your-broken-internet/angry-at-computer/
 http://computer.howstuffworks.com/wireless-network3.htm
 http://en.wikipedia.org/wiki/Wi-Fi
 http://www.cambridgenow.ca/cnt/files/1CambridgeNowEditorial%202011/CMH%202011//MRI-
Machine.jpg
 http://science.howstuffworks.com/radar.htm
 http://www.clker.com/clipart-radar.html
 http://science.hq.nasa.gov/kids/imagers/ems/
 http://auto.howstuffworks.com/radar-detector1.htm