RECENT TRENDS IN WIRELESS, RADIO AND SATELLITE COMMUNICATION: A SURVEY ON WIRELESS FIDELITY :TECHNOLOGY AND STANDARDS

Authors :  Deepak Mathur¹,Shishir Jain²

¹[Asst. Professor (Comp. Sc.), Lachoo Memorial College of Science and Technology Jodhpur 342003, ]

2[Student (MCA IV), Lachoo Memorial College of Science and Technology, Jodhpur 342003]

Abstract

Wi-Fi stands for Wireless Fidelity. Wi-Fi is based on the IEEE 802.11 family of standards and is primarily a local area networking (LAN) Technology. The number of computing and telecommunications devices are  increasing and consequently the focus on how to connect them to each other. The Solution is to connect them by the cable or by the Wireless technology Wi-Fi offers us remarkably higher peak data rates. So that do 3G systems, primarily since it operates over a larger 20MHz bandwidth. In this paper we are going to survey on wi-fi technology and the standards that are followed.

Keywords: WiFi, WSE,WSM

1 . Introduction:

Wireless Stands for Wireless Fidelity. Wi-Fi is based on the IEEE 802.11 family of standards. Current Wi-Fi systems based on IEEE 802.11a/g support a peak physical-layer data rate of 54Mbps and typically provide indoor coverage over a distance of 100 feet. Today Wi-Fi becomes for last feet broadband connectivity in homes, offices, and public hotspot locations. Vic haves is the person who is called “Father of Wi-Fi”. The first wireless products were under the name WaveLan. Current Wi-Fi systems based on IEEE 802.11a/g support a peak physical-layer data rate of 54Mbps and typically provide indoor coverage over a distance of 100 feet.

2. Wi-Fi Working Concept

2.1 Radio Signals:

Radio Signals are the keys which make WiFi networking possible. These radio signals transmitted from Wi-Fi antennas are picked up by WiFi receivers such as computers and cell phones that are equipped with WiFi cards. Whenever a computer receives any of the signals within the range of a WiFi network which is usually 300 - 500 feet for antennas, the WiFi card will read the signals and thus create an internet connection between the user and the network without the use of a cord. Access points which consist of antennas and routers are the main source which transmit and receive radio waves. Antennas work stronger and have a longer radio transmission with a radius of 300-500 feet which are used in public areas while the weaker yet effective router is more suitable for homes with a radio transmission of 100-150 feet.

2.2  Wi-Fi Cards:

WiFi cards can be external or internal, if a WiFi card is not installed in our computer, we  may purchase a USB antenna attachment and have it externally connect to our USB port, or have an antenna-equipped expansion card installed directly to the computer. For laptops, this card will be a PCMCIA card in which we insert to the PCMCIA slot on the laptop.

2.3 Wi-Fi Hotspots:

A Wi-Fi hotspot is created by installing an access point to an internet connection. The access point transmits a wireless signal over a short distance . typically covering around 300 feet. When a Wi-Fi .enabled device, such as a Pocket PC, encounters a hotspot, the device can then connect to that network wirelessly.

3  Wi- fi Quality of Services

There are plans to incorporate quality of service capabilities in Wi-Fi with the adoption of the IEEE 802.11e standard. The 802.11e standard will include two operating modes, either of which can be used to improve service for voice:

 

3.1 Wi-Fi Multimedia Extensions (WME):

This uses a protocol called Enhanced Multimedia Distributed Control Access (EDCA), which is Extensions an enhanced version of the Distributed Control Function (DCF) defined in the original 802.11 MAC.

The enhanced part is that EDCA will define eight levels of access priority to the shared wireless channel. Like the original DCF, the EDCA access is a contention-based protocol that employs a set of waiting intervals and back-off timers designed to avoid collisions. However, with DCF, all stations use the same values and hence have the same priority for transmitting on the channel.

 

3.2 Wi-Fi Scheduled Multimedia (WSM):

True consistent delay services can be provided with the optional Wi-Fi Scheduled Multimedia (WSM). WSM operates like the little used Point Control Function (PCF) defined with the original 802.11 MAC.

In WSM, the access point periodically broadcasts a control message that forces all stations to treat the channel as busy and not attempt to transmit. During that period, the access point polls each station that is defined for time sensitive service.

4. Wi-Fi Standards

Standard	Data Rate	Modulation Scheme	Security	Pros/Cons & More Info
IEEE 802.11	Up to 2Mbps in the 2.4GHz band	FHSS or DSSS	WEP & WPA	This specification has been extended into 802.11b.
IEEE 802.11g (Wi-Fi)	Up to 54Mbps in the 2.4GHz band	OFDM above 20Mbps, DSSS with CCK below 20Mbps	WEP & WPA	Products that adhere to this standard are considered "Wi-Fi Certified." May replace 802.11b. Improved security enhancements over 802.11. Compatible with 802.11b. 14 channels available in the 2.4GHz band (only 11 of which can be used in the U.S. due to FCC regulations) with only three non-overlapping channels.
Bluetooth	Up to 2Mbps in the 2.45GHz band	FHSS	PPTP, SSL or VPN	No native support for IP, so it does not support TCP/IP and wireless LAN applications well. Not originally created to support wireless LANs. Best suited for connecting PDAs, cell phones and PCs in short intervals.
HiperLAN/1 (Europe)	Up to 20Mbps in the 5GHz band	CSMA/CA	Per-session encryption and individual authentication.	Only in Europe. HiperLAN is totally ad-hoc, requiring no configuration and no central controller. Doesn't provide real isochronous services. Relatively expensive to operate and maintain. No guarantee of bandwidth.

5. Conclusions

As per the above discussion there are following issues which are assumed to be the cause of the sluggish adoption of Wi-Fi technology:

·        Security Problems: Security concerns have held back Wi-Fi adoption in the corporate world. Hackers and security consultants have demonstrated how easy it can be to crack the current security technology, known as wired equivalent privacy (WEP), used in most Wi-Fi connections. A hacker can break into a Wi-Fi network using readily available materials and software.

·         Compatibility and Interpretability: One of the bigger problems with Wi-Fi is compatibility and interpretability, for example 802.11a products are not compatible with 802.11b products, due to the different operating frequencies, and 802.11a hotspots would not help a 802.11b client. Due to lack of standardization, harmonization and certification, different vendors come out with products that do not work with each other.

·         Billing Issues: Wi-Fi vendors are also looking for ways to solve the problem of back-end integration and billing that has dogged the roll-out of commercial Wi-Fi hotspots. Some of the ideas under consideration for Wi-Fi billing include per day, per hour and unlimited monthly connection fees.

·         Use this wireless networking standards chart to get quick information to help we differentiate between the available wireless networking standards and choose which standard might be the right fit for wer business. See the links below the chart for further information on wireless networking standards.

First in the world

First in The World

• The First Person to cross the Atlantic in an open wicker basket hot air Balloon : David Hemapleman Adams

• The First Woman Civilian Police adviser of the U. N.: Kiran Bedi

• The First person in the world to land in the moon : Neil Armstrong and Edwin E. Aldrin

• The First man to enter space: Major Yuri Gafarin(Russian)

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• The First woman cosmonaut of the world: Velentina Tereshkova

• The First Space Vehicle to land on the moon : Lunar Exploration Module(LEM) Nick-Named ‘Eagle’

• The First space ship which carried three American astronauts to land two of them on the moon : Apollo-11

• The Firstcountry to send man to the moon: USA

• The First space rocket brought back to earth after orbiting the moon: Zond-5

• First crew transfer betweeen the orbiting space ships: Soyuz T-15 with Mir Space Station.

• The first mission of a ling-up in space by manned space ships of USA and Soviet Union: Apollo-Soyuz Test Project Mission(ASTP) (launched on July 15 and linked up in space on July 17,1975

• The first man to fly into space belonging to a country other than Russia or the USA: Remek (Czechoslovakia)

• The first to launch earth satellite or artificial baby moon: USSR

• The first spaceship in the world to sample moon’s crust: Surveyor-3(USA)

• The first space vehicle to soft land on moon: Luna 9 (USSR)

• The first manned spaceship to perform the longest stay in space (11 days): Apollo-7 (USA)

• The first man to win 4 Olympic gold medals: Alvin Kranzein (USA) in 1900

• The first lawn tennis player who won the Wimbledon championship for five years consecutively: Bjorn Borg

• First batsman to score three Test Century in three successive Tests on debut: Mohd. Azharuddin (India)

• World’s first Cricketer to score more than, 11,000 runs in his test carrier: Allan Border of Aushtralia swith more than 11,000 runs.

• The first person to reach the South Pole: Amundsen (Norway)

• The first person to have climbed Mount Everst: Edmund Hillary and Sherpa Tenzing 19^th May,1953

• The firstperson to sail round the world: Ferdinanad Magellan (Portugal)

• The first man to have climber Mount Everest Twice: Nawant Gombu

• The first vessel ever to reach the North Pole by sailing thought the thick Arctic ice: Soviet Arktika Atomic-powered (ice-breaker)

• The leader of the expedition ‘Ocean to Sky’: Sir Edmund Hillary

• The first two mountaineers who reached the summit of Everest without using oxygen: Peter Habeler (Austria) and Reinhold Messner (Italy)

• The first woman Prime Minister of a country twice: Mrs. S.Bandarnaike (Sri Lanka)

• The first Presideint of the USA: George Washington

• The first President of the Chinese Republic: Sun Yet Sen

• The first European to visit China: Marco Polo

• The first US President to resign Presidency: Richard Nixon

• The first woman Ambassador of Britain: Anne Warburton

• The first woman Prime Minister of a European Country: Margaret Thatcher

• Woman Bishop: Rev Barbara C. Harris (USA)

• Lady President of a country: Maria Estela Person (Argentina)

• The first Muslim women to win Nobel Prize: Shirin Ebadi.

• Civilian Police Advisor in U.N.: Ms. Kiran Bedi.

• 400 Run maker in an inning of Test Cricket: Brain Lara

• Claimer of hat-trick in very first over of test match cricket: Irfan Pathan (India)

• One Thousand wicket taker in International cricket: M.Murlitharan (Sri Lanka)

• Highest Runs in Test Matches and ODI: SachinTendulkar

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FIRST IN INDIA

FIRST IN INDIA

· British Governor: Warren Hastings

· British Governor-General of Independent India: Lord Mountbatten

· Justice of India: Hiralal J.Kania

· Commander-in-Chief of Free India: General K.M. Cariappa

· Chief of Air Staff: Air Marshal Sir Thomas Elmhirst

· Indian Air Chief: Air Marshal S. Mukherjee

· Chief of Army Staff: General M. Rajendra Singh

· Chief of Naval Staff: Vice-admiral R.D.Katari

· Cosmonaut: Sqn. Ldr. Rakesh Sharma

· Emperor of Mughal Dynasty in India: Babar

· Field Marshal: SPFJ Manekshaw

· Governor-General of Indian Union: C. Rajgopalachari

· Indian to get an Oscar: Bhanu Athaiya

· Indian to Reach of South Pole: Col. I.K.Bajaj

· Indian ICS Officer: Satyendra Nath Tagore

· Indian Member of Viceroy’s Executive Council: Sir, S.P.Sinha

· Indian Man of Swim Across the English Channel: Mihir Sen

· Indian Woman to swim Across the English Channel: Miss Aarti Saha

· Indian Woman to swim Across the Strait of Gibraltar: Aarti Pradhan

· Man to Climb Mount Everest: Sherpa Tensing

· Man to Climb Mount Everest without Oxygen: Phu Dorjee

· Man to Climb Mount Everest twice: Nawang Gombu

· Muslim Woman to sit on the throne of Delhi: Razia Sultana

· Nobel Prize Winner: Rabindra Nath Tagore

· President of the Indian National Congres: W.C.Banerjee

· Woman President of the Indian National Congress: Annie Besant

· President to Die in Office: Dr. Zakir Hussain

· Prime Minister to Lose an Election: Indira Gandhi

· Prime Minister to Resign from Office: Morarji Desai

· Deputy Prime Minister: Vallabhbhai Patel

· Talkie Film: Alam Ara (1931)

· Test-tube Baby: Indira (Baby Harsha)

· Viceroy : Lord Canning

· Woman Chief Minister of State: Mrs. Sucheta Kripalani

· Woman Central Minister: Rajkumari Amrit Kaur

· Woman Governor: Mrs. Sarojini Naidu

· Woman Minister: Mrs. Vijayalakshmi Pandit

· Woman to Climb the Mt. Everest: Bachendri Pal

· Woman Prime Minister: Mrs. Indira Gandhi

· Woman Speaker of a State Assembly: Mrs. Shanno Devi

· Woman Airline Pilot: Durba Banerjee

· Woman to Win an Asiad Gold: Kamaljit Sandhu

· Woman Judge of the Supreme Court: Fathima Beevi

· Woman IPS Officer: Kiran Bedi

· Indian in the British Parliament: Dadabhai Naoroji

· Indian to win Miss Universe Title: Ms. Sushmita Sen

· Indian Woman Congress President: Sarojini Naidu(1925)

· Woman president of UN General Assembly : Vijayalakshmi Pandit

· Woman to win the Nobel Prize : Mother Teresa(1979)

· Woman to become ‘Miss World’ : Reeta Faria

· Speaker, Lok Sabha : G. V. Manavalankar(1952-57)

· Chairman Rajya Sabha : S. V. Krishnamoorthy (1952)

· Indian to pass ICS : Surendra Nath Banerji(1862)

· Indian Pilot : JRD Tata(1929)

· To reach Antarctica : Lt. Ram Charan(1960)

· Telegraph Line Installed : Calcutta to Diamond Harber(1853)

· Silent Movie : Raja Harish Chandra by Dada Saheb Phalke(1913)

· Colored Cinemascope Film : Pyar ki Pyas(1961)

· Satellite Launched : Aryabhatta(1975)

· Atomic Device exploded at : Pokharan in Rajasthan(1974)

· Indigenously Designed and built missile: Prithvi (1988)

· Member of the Dalit Community to become the president of India : K. R. Narayanan

· Electric Train started between : Ludhiana and New Delhi

· Science city was inaugurated in : Kolkata

· Actress of Indian Cinema : Kamalabai Gokhale

· Woman Pilot of IAF : Harita Deol

· Indian writer to win the Booker Prize: Arundhati Roy

· Musician to be Awarded the Bharat Ratna : M. S. Subbulakshmi

· Indian Woman to go into Space: Kalpana Chawala

· Chairman of the Prasar Bharti Board : Nikhil Chakravarthy

· Woman to win an Olympic Medal : Karanam Malleswari

· Woman Foreign Secretary of India : Chokila Iyer

· Indian Grand Master (in Chess) : Vishwanathan Anand

· Chinese pilgrim to visit India : Fahien

· European invader on India soil : Alexender , the great

· Indian to win World Chess Championship : Vishwanathan Anand

· Woman Air vice Marshal : P. Bandopadhyaya

· Lady Cadet of Indian Army : Pryia Jhingan

· First Indian to win a medal in the worlds Athletic Championship : Anju B. George (2003)

· Triple Century Maker in Test Cricket : Virendra Sahwag (2004)

· Medal winner in Olympic Games: Rajyawardhan Singh Rathore(2004)

· Formula-1 Grand Prix Winner : Naryan Kartikeyan

· Asian Tennis Champion, WTA Champion, Third round winner in Grand Slam Tournament Match Winner in U.S. open : Sania Mirza(2005)

· Indian to be awarded ‘Srilanka Ratna’: N.Ram (2005)

· Woman Commanded the annual passing out parade: Wahida Prizm(2006)

· To the ski to the North Pole: Ajeet Bajaj (2006)

· First Air Chief to Sky-dive: Air Chief S.P.Tyagi (2006)

· First Indian Woman to win a badminton Grand Prix: Saina Nehwal

· First President to make a sortie in a combat aircraft: Dr. A.P.J. Abdul Kalam (2006)

· Judge in USA Court: Savita Singh

· First Indian Woman President: Pratibha Devisingh Patil (2007)

· Chief, British Broad easting Corporation : Chtitra Barucha

· Governor in U.S.A. of Indian origin: Bobby Jindal

· Secretary General, Common wealth : Kamlesh Sharna

· Gold Medal Winner in Olympic Games: Abhinav Bindra(Beijing Olympic,2008)

· Bronze Medal Winner Boxer in Beijing Olympic ,2008: Vijendra

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Why we should hire u

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what is your the greatest Achivement

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Personality Test

Fill in using the appropriate response as given below:
Never (1) Sometimes (2) Frequently (3) Always (4)

1. When my feelings are hurt I express this…………….(1 or 2 or 3 or 4)
2. Others value my opinions………………..
3. I feel intellectually capable……………..
4. I feel worthy of the gifts that have been offered to me…………….
5. I am satisfied with my personal development up to now…………..
6. I consider comparing myself with other people to be a waste of time…………….
7. I enjoy meeting and talking with new people. …….
8. I feel comfortable in social gatherings……………
9. I am happy to be me and wouldn’t want to be anybody else ……
10. I like my present life situation………….
11. I am happy with the way I live my life. ……..
12. I like my present place and residence……….
13. I enjoy my work…………….
14. People admire me. …….
15. I am considerate about others. ……..
16. I enjoy getting up in the mornings ……
17. I am self-reliant. …….
18. I make a big contribution to the lives of others. …….
19. I enjoy attending to my own needs: in eating, exercise and general care of myself………….
20. I try to make sure I lead a balanced life-enough rest, work, play……….
21. I enjoy my time alone………..
22. I like myself……….
23. I respect myself………..
24. I value myself………..
25. I see myself as a good-looking person. …..
26. I see myself as attractive to the opposite sex………..
27. I think of myself as a loving person……….
28. I think of myself as a confident person………..
29. I think of myself as a sharing person…………..
30. I see my self as a successful person…………….

Count your score: My score is …………
if your score is above 80:
You are a high achiever with a high degree of self-esteem. You should analyse how you can improve further so that you can take up leadership responsibilities in your chosen field.
If your core is between 51 and 80:
You are reasonably successful with high self-esteem. Still, you need to hone your communication skills. You should also develop better self-esteem by undertaking challenges and overcoming them. There is no greater morale booster than the thrill of confronting head-on real challenges as they unfold.
If your core is between 21 and 50:
You have hidden potential but unfortunately you are a medium achiever possibility due to low self-esteem and fear of failure or opposition. Don’t worry about themand do what you think is correct. Success will be yours, if not now, definitely soon. Remember, the man who wins is the one who thinks he can!
if your core is 20 or less:
You are a somewhat low achiever with very low self-esteem. You should actively try to improve your personality. Is is never too late.

Source: Aryan International College, Ajmer