Friday, 4 May 2012

Sixth Footmark on 2nd May

Introduction to Wireless Technology 


* Joke *

When Alex was young he used to pray for a bike,
 then he realized that God doesn't work that way, 
so he stole a bike and prayed for forgiveness.

 * Good Picture *

  * Enjoy it *


...How Do I Feel....

Basically, we learnt about the wireless in this lesson, so there was quite interesting to know how the signal being transferred from one place to another place via devices.

Besides that, we also know new knowledge about antennas, horn, satellite, and so on...

In addition, two groups of my friends have presented their slide to us, regarding about the creation of website and uploading the music or video to website... that were fun and useful to us...

"Formal education will make you a living. Self-education will make you a fortune."

The lesson I learnt today....

Require line-of-sight transmission and reception equipment
The taller the antennas the longer the sight distance
Towers = on hills/mountains

2 types of antennas:
1.Parabolic dish
Parabolic dish: based on geometry of parabola
Works like a funnel (catching a wide range of waves and directing to a common point call focus)

2. Horn

Looks like gigantic scoop
Outgoing transmission are broadcast up a stem & deflected outward in a series of narrow parallel beams by the scooped shape of the horn.

3. Satellite

Satellite acting as a super tall antenna and repeater
Single bounce
Capability = any location on earth no matter how remote 
Transmission from earth to satellite = uplink 
Transmission from the satellite to earth = downlink

1. Wireless technology 
-        is generally used for mobile IT equipment. It encompasses cellular telephones, personal digital assistants (PDA's), and wireless networking.

2. Wireless networking technologies 
-        range from global voice and data networks, which allow users to establish wireless connections across long distances, to infrared light and radio frequency technologies that are optimized for short-range wireless connections.
 3. Wireless communication involves
radio frequency communication.
microwave communication, for example long-range line-of-sight via highly directional antennas, or short-range communication.
infrared (IR) short-range communication, for example from remote controls or via IRDA.

Applications may involve
and other wireless networks.

4. Type of Wireless Network

-Wireless wide area networks (WWANs)
-Wireless metropolitan area networks (WMANs)
-Wireless local area networks (WLANs)
-Wireless personal area networks (WPANs)

5. Application : Data Networking. 


Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances (using short-wavelength radio transmissions in the ISM band from 2400–2480 MHz) from fixed and mobile devices, creating personal area networks (PANs) with high levels of security. Created by telecoms vendor Ericsson in 1994, it was originally conceived as a wireless alternative to RS-232 data cables. It can connect several devices, overcoming problems of synchronization.


 Wi-Fi 6. 
is a brand originally licensed by the Wi-Fi Alliance to describe the underlying technology of wireless local area networks (WLAN) based on the IEEE 802.11 specifications. 
Broadband wireless access7. 
is a technology aimed at providing high-speed wireless access over a wide area from devices such as personal computers to data networks. According to the 802.16-2004 standard, broadband means 'having instantaneous bandwidth greater than around 1 MHz and supporting data rates greater than about 1.5 Mbit/s'.
It is planned to be used in the next few years and is estimated to have a range of 50km (30 miles). 

8. 3G vs 4G

How much faster is 4G compared to 3G and what applications run better on 4G?

3G and 4G are standards for mobile communication. Standards specify how the airwaves must be used for transmitting information (voice and data). 3G (or 3rd Generation) was launched in Japan in 2001. As recently as mid-2010, the networks for most wireless carriers in the U.S. were 3G. 3G networks were a significant improvement over 2G networks, offering higher speeds for data transfer. The improvement that 4G offers over 3G is often less pronounced. Analysts use the analogy of standard vs Hi-Def TV to describe the difference between 3G and 4G.

                                                                           Comparison chart

3G 4G
Data Throughput: Up to 3.1mbps Practically speaking, 3 to 5 mbps but potential estimated at a range of 100 to 300 mbps.
Forward error correction (FEC): 3G uses Turbo codes for error correction. Concatenated codes are used for error corrections in 4G.
Frequency Band: 1.8 – 2.5GHz 2 – 8GHz
Services And Applications: CDMA 2000, UMTS, EDGE etc Wimax2 and LTE-Advance
Network Architecture: Wide Area Cell Based Integration of wireless LAN and Wide area.
Peak Upload Rate: 50 Mbit/s 500 Mbit/s
Peak Download Rate: 100 Mbit/s 1 Gbit/s
switching technique: packet switching packet switching, message switching      

9. Unbounded and bounded media

 Bounded media are those that use cables for transmitting electricity or light; unbounded media does not require cabling and includes satellite, microwave and radio transmission. Wireless connections, including 802.11b and 802.11g, are examples of unbounded media. Today, bounded media continue to be more common than unbounded.



How does satellite work???


Which is Faster? 3G vs 4G Speed Test - iPhone 4 on AT&T, EVO on Sprint

*  Learn something new.Try something different.Convince 

yourself that you have no limits. * 


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