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K.S.RANGASAMY COLLEGE OF

TECHNOLOGY

TIRUCHENGODE -637215

DEPARTMENT OF COMPUTER SCIENCE

AND ENGINEERING

PAPER PRESENTATION ON

LATEST TRENDS IN IT

Hybrid positioning system (xps)

submitted by,

L.ARTHI

Pre-final year

Register no:0714109

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ABSTRACT:

Our ancestors had to go to pretty extreme measures to keep from getting lost.

They erected monumental landmarks, laboriously drafted detailed maps and learned to read

the stars in the night sky. But things are much, much easier today. You can know exactly

where you are on Earth at any moment with the help of positioning system like and hence

you'll never be lost again. Towards this aim, several technologies exist, ranging from personal

area networking, to indoor, outdoor, and up to geographic area systems.Inspite of the pool of

positioning technologies ,we are in search of “THE BEST” technology .

Towards this aim, the paper proposes a HYBRID POSITIONING SYSTEM

which is the combination of several positioning system existing around the globe. This hybrid

positioning system is the best, because it takes into account the merits of several positioning

systems like GPS, Wi-Fi, cell tower triangulation and many more. Therefore overcomes or

solves all the inefficiency problems and provides more accuracy. The positioning system has

proven possibility of providing positional information with high accuracy as a

complementary system of GPS even in the areas where GPS signal is not available.

XPS is a software-only location platform based on Wi-Fi positioning, GPS

and Cell tower triangulation.XPS is available world wide and can be deployed on a broad

range of mobile devices. Hence a mobile device with XPS client collects raw data from each

of the signal sources and sends the information to the XPS server. As a result a single

location is estimated and returned to the mobile device.XPS is able to quickly and accurately

calculate location regardless of the physical environment. The XPS database is created by

collecting all the Wi-Fi access points and cellular tower IDS in the particular area, hence the

XPS system is always expanding. Hence the customers can easily locate the position in both

indoor and dense urban areas.

The commercial application of XPS is that of the Global positioning system and

Wi-Fi, but the basic difference lies in the accuracy, efficiency and liability. To cite the

application includes navigation, locating the position through iphones, vehicle tracking and

many more.

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Hence the hybrid positioning system is Accurate, Available and Reliable.

Abstract: Our ancestors had to go to pretty extreme measures to keep from getting lost. They erected monumental landmarks, laboriously drafted detailed maps and learned to read the stars in the night sky. But things are much, much easier today. you can know exactly where you are on Earth at any moment with the help of positioning system and hence you'll never be lost again. Towards this aim,several technologies exist, ranging from personal

area networking, to indoor, outdoor, and up to geographic area systems.Inspite of the pool of positioning technologies ,we are in search of “THE BEST” . Towards this aim, the paper proposes a HYBRID POSITIONING SYSTEM which is the combination of several positioning system existing around the globe.This hybrid positioning system is the best,because it takes into account the merits of several positioning sysetems like GPS,Wi-Fi,cell tower triangulation and many more.The positioning system has proven possibility of providing positional information with high accuracy as a complementary system of GPS even in the areas where GPS signal is not available.

introduction:

Hybrid positioning systems are systems for finding the location of a mobile

device using several different positioning technologies combined with cell

tower signals, wireless internet signals, Bluetooth sensors or other local

Positioning Systems.These systems are specifically designed to overcome

the limitations of GPS, which is very exact in open areas, but works poorly

indoors or between tall buildings (due to the urban canyon effect) By

comparison, cell tower signals are not hindered by buildings or bad

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weather, but usually provide less precise positioning. Wi-Fi signals may

give very exact positioning, but only in urban areas with high Wi-Fi density

- and depend on a comprehensive database of Wi-Fi access points.Hybrid

positioning systems are increasingly explored for certain civilian and

commercial location-based services and location-based media. which need to

work well in urban areas in order to be commercially and practically viable.

Different hybrid positioning systems are currently being developed and used in

services from Navizon, Xtify, PlaceEngine, SkyHook, Google Maps for Mobile

for application in smartphones including Apple iPhone. The maturity of these

systems approaches requires proofing in operational use.

skyhook's xps:

Skyhook was founded in 2003 to capitalize on the increasing demand for

location-based services. The first location technologies, GPS and cell tower

triangulation, were inadequate - leaving frustrated mobile consumers with slow

and inaccurate positioning information. In response, Skyhook developed the

Wi-Fi Positioning System (WPS). Taking advantage of the hundreds of millions

of Wi-Fi access points throughout populated areas, WPS consistently provides

accurate location information indoors and in urban areas.

Skyhook also provides XPS, the world's first true hybrid positioning system.

Taking advantage of the relative strengths of several location technologies,

WPS, GPS, cellular tower triangulation, XPS is the fastest, most accurate, most

reliable and most flexible location system on the market today. Skyhook's

patented XPS technology is positioned to location-enable hundreds of millions

of applications and mobile devices, including smartphones, netbooks, laptops,

and gaming devices. From traditional navigation apps to cutting edge

augmented reality browsers, today's mobile applications require location that

works reliably and quickly everywhere consumers travel, from rural to urban

areas, indoors and outside.

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XPS is the only location system that meets today's consumer, developer and

device maker demands for location performance.

WORK: XPS is a software-only location platform that can quickly determine the location of any Wi-Fi enabled mobile device with an accuracy or 10 to 20 meters. To see Skyhook's hybrid positoning system (XPS) in action, view a demo now:

To quickly and reliably arrive at accurate location results, XPS synthesizes data

from Skyhook's Wi-Fi Positioning System (WPS), GPS satellites and Cell

Towers with advanced hybrid positioning algorithms. By leveraging the

strengths of more than one underlying position technology, XPS provides the

best location available to mobile applications and devices today.

The following graph illustrates the performance of XPS relative to assisted GPS

(A-GPS) and WPS.

XPS is configured to integrate and synthesize the location output of Skyhook's

Wi-Fi Positioning System (WPS), GPS and cellular towers (Cell ID). It then

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uses advanced hybrid positioning algorithms to combine each of these location

sources to arrive at a single position with a high degree of confidence.

Wi-Fi Positioning System (WPS)

WPS determines location based on Skyhook's massive worldwide database of

known Wi-Fi access points. It performs best where GPS is weakest, in urban

areas and indoors. It is an essential element in any consumer-ready location

system. Click here for details on Wi-Fi data collection methodology and

coverage.

GPS

GPS provides highly accurate location results in "open sky" environments, like

rural areas and on highways. But in urban areas and indoors, tall buildings and

ceilings block GPS' view of satellites, resulting in serious performance

deficiencies in time to first fix, accuracy and availability. Mobile app developers

and consumers now demand location information that is fast and accurate in all

environments. GPS or A-GPS alone cannot meet these standards.

In deep urban settings, WPS can also take advantage of faint GPS signals to

more accurately acquire location in just seconds.

Cell Tower Triangulation

Cell Tower Triangulation provides generalized location results with only 200 -

1000 meter accuracy. It serves as a coverage fallback when neither GPS nor

WPS is available. Skyhook maintains a worldwide database of cell tower

locations, which increases the XPS coverage area and helps improve GPS

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satellite acquisition time. Cell Tower Triangulation can also improve power

utilization by helping XPS intelligently enable/disable communication radios

depending on the location accuracy required.

COVERAG:

To pinpoint location, XPS uses a massive reference network comprised of the

known locations of over 100 million Wi-Fi access points and cellular towers. To

develop this database, Skyhook has deployed drivers to survey every single

street, highway, and alley in tens of thousands of cities and towns worldwide,

scanning for Wi-Fi access points and cell towers plotting their precise

geographic locations. Skyhook's extensive coverage area includes most major

metro areas in North America, Europe, Asia, and Australia.

Wi-Fi Reference and Cellular Database

Skyhook's Wi-Fi and cellular database is the largest and most extensive in the

world. Skyhook maintains the accuracy of this database through an ongoing and

continuous process of data monitoring, analysis, and collection. The three main

components are:

1. Baseline Data Collection and Establishing Coverage Areas

Data collection begins with identifying target geographic areas using population

analysis. Skyhook territory planners build coverage schedules starting with

population centers and then moving into residential and suburban areas.

Skyhook deploys a fleet of data collection vehicles to conduct a comprehensive

access point survey within the target coverage areas. Every single passable

street is included in the survey providing consistent coverage throughout the

territory.

2. Automated Self-Healing Network

Each location transaction starts with a scan for nearby access points and cell towers. The resulting access point information is then compared against the central reference network. Known access points and towers (those already in the reference network) are used to calculate the location of the device.

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Any access point or cell tower that is either not in the database or was previously associated with a different geographic location is automatically identified and its current position entered into the database. In this manner, XPS automatically fixes and expands the reference network as it is being used.

3. Periodic Rescan

Depending on the aging of the survey data and the density of user-generated updates, Skyhook periodically will rescan entire coverage areas to recalibrate the reference network, ensuring that performance remains consistent over time. Every territory added to Skyhook coverage is continuously monitored to assess the quality of the reference network and determine whether a rescan is required.

ARCHITECTURE:

There are two major components to the XPS system, the Mobile Location Client

(MLC) and the XPS Location Server. The nature of the interaction between the

two components and how often they communicate depends on the deployment

model that is adopted.

Mobile Location Client

The Mobile Location Client is the software location engine of XPS. All

applications and services request device location from the client. The MLC

manages the entire process, from optimizing power management on the device

to synchronizing reference data and calculating location. The client can operate

in a fully autonomous mode or over the network with the Location Server.

Mobile Location Server

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The Location Server plays a supporting role to the MLC, ensuring that the client

has the most up-to-date reference data for its region. The Location Server can

also execute positioning algorithms should the operator of the server prefer a

network-centric approach. The server includes components for metering and

tracking location requests in order to integrate with the operator's subscriber

management and billing system. The server is designed to fit into any device

maker or operator's existing location infrastructure. While many service

providers choose to run the Location Server within their network, Skyhook also

hosts a publicly available Location Server for providers that choose to minimize

their cost and complexity. Developers who access XPS via the Skyhook SDK

utilize the hosted server.

Configuration

XPS requires no new specialized hardware to operate on a device - only a "thin"

software client, which can be easily configured to run on most mobile devices.

This dramatically reduces the cost and time of deploying location-based

applications or services in comparison with other positioning technologies. XPS

complies with all location standards, simplifying the process of integrating with

applications via standard interfaces, such as NMEA, and integrating within

carrier networks via industry standards, such as SUPL. Device makers can

employ many different configuration options to balance the needs for network

availability, response time, and data storage in order to deliver the best user

experience.

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Click here to learn more about how XPS is configured to location-enable

devices. Click here to see how XPS can add location to different applications

and services.

PERFORMANCE:

PS provides a ubiquitous and reliable positioning system for any environment

and use case. Contrary to other positioning systems, XPS performs

exceptionally well in highly populated as well as indoor environments. The

speed, reliability, accuracy and flexibility of XPS exceeds those of all other

positioning systems.

Performance Table

XPS GPS A-GPS

Accuracy 10

meters

10

meters

30

meters

Availability 99.8% 80.0% 95%

Time-To-First-

Fix 1 sec 65 sec 30 sec

Unique technical differentiators

As a true hybrid positioning system that jointly optimizes raw location data

from different sources, XPS 2.0 offers many distinct advantages over other

hybrid systems. Some of these include:

1. Improving WPS accuracy by 35% in difficult environments, by

leveraging signals from just two GPS satellites

2. In deep urban settings, XPS uses weak GPS signals and WPS to

acquire a location 100% of the time (A-GPS works only 70% of

the time)

3. From a complete cold start, XPS delivers a full hybrid location

in 4 seconds (compared to 30-60 seconds for A-GPS)

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4. Combining GPS signals and WPS facilitate stationary detection

techniques which reduce jitter, improving the pedestrian

experience

re are millions of iPhones on the market today. Despite stunning sales figures, the iPhone's initial adopters shared a complaint: that it lacked accurate location technology. Without location awareness, the device could not help users find their own location, provide meaningful local search, or instant directions from a users' current location.

Apple wanted to add a software-only location system to the Wi-Fi-enabled

iPhone. It required superior performance, with quick time-to-fix and high

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accuracy in urban areas. Apple also required international coverage that would

match the iPhone's international deployment.

Apple needed revolutionary positioning to match its revolutionary devices. It

chose Skyhook's Wi-Fi Positioning System. Skyhook addressed Apple's needs

by providing a highly accurate, reliable, commercial-grade positioning system

that required no new hardware or complicated device integration.

When Apple's CEO Steve Jobs announced Wi-Fi location for Apple's mobile

devices at Macworld in January 2008, he commented on the technology: "Isn't

that cool? That's really cool.... And it works doggone well." After his

announcement, Wi-Fi location became available to all iPhone and iPod touch

users with a simple firmware upgrade.

1. On the left, iPhone without Skyhook: Imprecise and not

acceptable to users

2. On the right, iPhone with Skyhook: Accurate and meaningful for

users

iPhone 3G

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At the WWDC in June of 2008, Steve Jobs announced the revolutionary iPhone

3G. Skyhook's technology continues to be used on the iPhone 3G, as Jobs

emphasized the importance of having all three dominant location technologies

(GPS, WPS and Cell ID) on the iPhone: "Location services is going to be a

really big deal on the iPhone -- you saw a bit of that here today, it's going to

explode. We get location from cell towers, from WiFi, and now we get it from

GPS."

The deployment of Skyhook's location system on millions of iPhones and iPod

touch devices has won accolades from consumers, analysts, and the press

worldwide.