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WIRELESS TECHNOLOGYBRANCH - ELECTRONICS AND TELE COMMUNICATION PPT

TOPIC:-WIRELESS TECHNOLOGY

Presented by:- Ankit Hole(3rdyear KGIET)

Aditya Deshmukh(3rdyear KGIET)

INDEX

Introduction What is GPS How GPS works1. Triangulating from Satellites2. Measuring distance from a satellite3. Getting perfect timing4. Determining exact location Applications Of GPS WI-FI Conclusion References Thanks ABSTRACT

The primary means of communicating information of these days are voice and Internet. The unlimited accesses to Internet and sheer number of people connected to the Internet have made industry captain realize its potential. The industry now plans its marketing and communication strategies around the Internet. Today every banking to education, research to health-care is affected by it. E-mail is the way to communicate today. Practically who use the Internet uses E-mail. The wireless technologies and the Internet were growing separately. The wireless industry initially struggled within a number of issues like low bandwidth and low connection stability, to bring Internet to its users. They came together to form a common forum to tackle these issues. This forum is called the WAP. The wireless application protocol.

In this paper we are going to focus on the two most popular and most essential wireless technologies used in 21st century

1)GPS

2)WI-FISo to make aware about wireless technology its a small try by engineering studentsINTRODUCTION

Global positioning system (GPS), space-based radio navigation system, consisting of 24 satellites and ground support, that provides accurate, three-dimensional position, velocity, and time, 24 hours a day, everywhere in the world, and in all weather conditions. Because the user doesnt communicate to the satellite, GPS serves an unlimited number of users. What is GPS?

The Global Positioning System (GPS) is a worldwide radio-Navigation system formed from aconstellation of 24 satellites and their ground stations.GPS uses these "man-made stars" as reference points to calculate positions accurate. In a sense it's like giving every square meter on the planet a unique address.GPS receivers have been miniaturized to just a few integrated circuits and so are becoming very Economical. And that makes the technology accessible to virtually everyone. These days GPS is finding its way into cars, boats, planes, construction equipment, movie making gear, farm machinery, even laptop computers .How GPS works?

Here's how GPS works in five logical steps:

The basis of GPS is Triangulation from satellites.

We're using the word "triangulation" very loosely here because it's a word most people can

Understand, but purists would not call what GPS does "triangulation" because no angles are

Involved. It's really trilateration."Trilateration is a method of determining the relative positions of objects using the geometry of Triangles. To "triangulate," a GPS receiver measures distance using the travel time of radio signals. To Measure travel time, GPS needs very accurate timing which it achieves with some tricks. Along with distance, you need to know exactly where the satellites are in space. High orbits and Careful monitoring are the secret. Finally you must correct for any delays the signal experiences as it travels through the atmosphere

Triangulating from Satellites

Improbable as it may seem, the whole idea behind GPS is to use satellites in space as reference points for locations here on earth.

Suppose we measure our distance from a satellite and find it to be 11,000 miles .Knowing that we're 11,000 miles from a particular satellite narrows down all the possible locations we could be in thewhole universe to the surface of a sphere that is centered on this satellite and has a radius of 11,000miles.

Next, we measure our distance to a second satellite and find out that it's 12,000 miles away. That tells us that we're not only on the first sphere but we're also on a sphere that's 12,000 miles from the second satellite. Or in other words, we're somewhere on the circle where these two spheres intersect.If we then make a measurement from a third satellite and find that we're 13,000 miles from that one, that narrows our position down even further, to the two points where the 13,000 mile sphere cuts through the circle that's the intersection of the first two spheres.

So by ranging from three satellites we can narrow our position to just two points in space. We saw in the last section that a position is calculated from distance measurements to at least three satellites. In the case of GPS we're measuring a radio signal so the velocity is going to be the speed of light or roughly 186,000 miles per second. These two versions would be out of sync. The version coming from the satellite would be a little delayed because it had to travel more than 11,000 miles. If we wanted to see just how delayed the satellite's version was, we could start delaying the receiver's version until they fell into perfect sync. The amount we have to shift back the receiver's version is equal to the travel time of the satellite's version. So we just multiply that time times the speed of light and BINGO! we've got our distance to the satellite Getting perfect timing Satellite Positions

The Air Force has injected each GPS satellite into a very precise orbit, according to the GPS master plan

Satellite Positions

The Air Force has injected each GPS satellite into a very precise orbit, according to the GPS master plan.

GPS Master Plan

The launch of the 24th block II satellite in March of 1994 completed the GPS constellation.

Four additional satellites are in reserve to be launched "on need."

The spacings of the satellites are arranged so that a minimum of five satellites are in view from every point on the globe.

Putting GPS to work

GPS technology has matured into a resource that goes far beyond its original design goals. These days scientists, sportsmen, farmers, soldiers, pilots, surveyors, hikers, delivery drivers, sailors, dispatchers, lumberjacks, fire-fighters, and people from many other walks of life are using GPS in ways that make their work more productive, safer, and sometimes even easier.

In this section you will see a few examples of real-world applications of GPS. These applications fall into three broad categories.

Location - determining a basic position

Navigation - getting from one location to another

Timing - bringing precise timing to the world

APPLICATION OF GPS :Natural Resource Application: Natural resource specialists, such as foresters, geologists, geographers, and biologists, use GPS mapping systems to record GPS position and attribute information. For example, foresters record, attribute information about age, health, quantity, and type of timber.Urban Application: Urban application of GPS mapping systems includes mapping transportation and utility infrastructure. Streets and highways are digitized by driving along the roads while recording the GPS positions.Agricultural Mapping: GPS mapping systems help delineate field characteristics for farming. Microclimates, soil types, crop stress, weed infestations, plant diseases, insect damage, and crop yield are recorded and referenced directly to this location.Social Science Application: Archaeologists and historians use GPS mapping systems to navigate to and record information about unmarked sites. These locations are recorded using a data collector and are called waypoints. Waypoints are useful for navigation to a location.WI-FIINTRODUCTION

What is mean by Wi-Fi?

Suppose that a businessman is attending conference. He has his laptop with him and at the same time he want some information from Internet too quickly & easily without worrying about finding a wired connection. Then what will be the solution ? For this the solution is Wi-Fi that is you can connect your PCs with the net wirelessly. Wi-Fi is the acronym for wireless fidelity. It is new advancement in WLAN (Wireless Local Area Networks) technology. It is discovered in 2002 .

WLAN & HOW IT WORKS:

A wireless LAN (WLAN) is a flexible data communication system implemented as an extension to, or as an alternative for, a wired LAN within a building or campus. Using electromagnetic waves, wireless LANs transmit and receive data over the air, minimizing the need for wired connections. Thus, wireless LANs combine data connectivity with user mobility and through simplified configuration, enable movable LANs.Also,

Security:

Wireless security is important and all Wi-Fi wireless networks provide wired equivalent privacy (WEP) a basic encryption technology that can prevent eavesdropping. Some Wi-Fi certified access points or gateways also provide access control function to restrict access to Wi-Fi network.

WEP is designed to make the security of the wireless medium equal to that of a wired medium. WEP encryption prevents unauthorized access to the network as well as the capture of wireless LAN traffic. WEP uses a shared key system, whereby both the wireless enabled computer and the access points are given the same key string, and the device without this key is denied access.

ADVANTAGES

1. Flexible: With a wireless network any businessman and his staff can have uninterrupted access to people, information and tools as he and his staff move through the workplace with their mobile pc.

2. Responsive: As you change your business operations, your wireless network can change with you.

3. Customized: Your wireless network can be configured the way you want it-even combined with your current wired network.

4. Fast: 11Mbps throughput and advanced roaming capabilities provide reliable access to e-mail, net, file sharing and other network resources away from the desk.

5. Cost-effective: Expand and extend your existing network by simply adding more adapters and access points.

6. Secure: Current STDs utilize 64 and 128-Bit WEP encryption to help guard the network from intruders and protect data in transit.

7. Wi-Fi is superior to 3G in terms of supported data rate.

Disadvantages:

1. Roaming and Billing problem: When user hand off from one carrier to another it is not transparent to user. Due to this user have to pay different charges

.

2. Due to 2.4GHz band microwave ovens are major source of interference.

3. Due to many wireless devices using this band high congestion occurs

.

4. Because it is unlicensed additional applications may target this band in future.

5. Also here as we go on increasing the range data rate decreases.

APPLICATIONS:-1. It can bring broadband access to underserved populations at a fraction of the cost alternative wired or wireless technologies.

2. Office Wi-Fi: It can send instant messages to your co-workers while you are sitting in a conference room. Also it enables staff to access the net wherever they are: meeting room, boardroom, between buildings, shop floor or warehouse. Hence costs of office relocation can be saved as rewiring & reconfiguration is eliminated. Due to this productivity increases. In such cases it supports a maximum of 256 users.

3. School Wi-Fi: It enables teacher and learners to have access to information and courses in any place. Hence there is improved delivery of course material, delivered online in real time.

4. Home Wi-Fi: A Wi-Fi network can connect a family's computers together to share such hardware and software resources as printers and the net. That means everyone in family can share stored files, photos, and documents and print them out on a single printer attached to one desktop computer -all without unsightly cables running throughout the home.

5. Many airports, hotels, coffee shops, industries etc. are implementing this technology.

CONCLUSION:

As the world walking with the new technologies, GPS is adding one step for going forward.GPS technology has matured into a resource that goes far beyond its original design goals. These days scientists, sportsmen, farmers, soldiers, pilots, surveyors, hikers, delivery drivers, sailors, dispatchers, lumberjacks, fire-fighters, and people from many other walks of life are using GPS in ways that make their work more productive, safer, and sometimes even easier GPS changed the navigation forever and soon it will become almost as basic as telephone.

Indeed we think it just may become a universal utility.

The public access WLAN i.e. Wi-Fi is projected to be a hot growth opportunity over the next several years.

For Wi-FI challenges are more business related, not technical, and can be overcome through the co-operation of many diverse. Manufacturers and service providers.

Soon Wi-Fi access may be like visa :

Anywhere you want access

to net you can REFERENCES :-

1. Efy

2. PCQuest Magazine

3. www.google.com4. www.webopedia.comwww.electronicforu.com For more information on GPS, consult the following:

GPS, A Guide to the Next Utility, Trimble Navigation Limited,

www.trimble.com, part number 16778.

Differential GPS Explained, Trimble Navigation Limited,

www.trimble.com, part number 23036.

THANKING YOU Dr. Sau. Kamaltai Gawai Institute of Engineering & Technology, Darapur PRAYUKTI13 Members who allows us to present this paper.

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