InformatIon ScIence Reference Part 7 ppt

The GPS technology and its analogs Global Navigation Satellite System or GLONASS in Rus-sia and the proposed Galileo system in Europe have proven to bethe most cost-effective, fastest, a



Time of Arrival (TOA): The position of

a device can be determined by measuring the

transferring-time of a signal between the device

and the COO

Time Difference of Arrival (TDOA):

Deter-mining a more precise position information of a

device by taking advantage of a cells infrastructure

and measuring the transferring time of a device

to three or more antennas

Ubiquitous Information Management (UIM): A communication concept, which is

free from temporal and, in general, from spatial constraints

Ultra Wideband (UWB): A technology

which enables very short-range positioning formation

Temple University, USA

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Abstr Act

Since the 1990s, the integration of GPS and GIS has become more and more popular and an industry standard in the GIS community worldwide The increasing availability and affordability of mobile GIS and GPS, along with greater data accuracy and interoperability, will only ensure steady growth of this practice in the future This chapter provides a brief background of GPS technology and its use in GIS, and then elaborates on the integration techniques of both technologies within their limitations It also highlights data processing, transfer, and maintenance issues and future trends of this integration.

The use of the Global Positioning System (GPS)

as a method of collecting locational data for

Geo-graphic Information Systems (GIS) is increasing

in popularity in the GIS community GIS data is

dynamic – it changes over time, and GPS is an

effective way to track those changes (Steede-Terry,

2000) According to Environmental Systems Research Institute (ESRI) president Jack Dan-germond, GPS is “uniquely suited to integration with GIS Whether the object of concern is moving

or not, whether concern is for a certain place at

a certain time, a series of places over time, or a place with no regard to time, GPS can measure

it, locate it, track it.” (Steede-Terry, 2000)



Although GIS was available in the market in the

1970s, and GPS in the 1980s, it was only in the

mid-1990s that people started using GPS coupled to

GIS The GPS technology and its analogs (Global

Navigation Satellite System or GLONASS in

Rus-sia and the proposed Galileo system in Europe)

have proven to bethe most cost-effective, fastest,

and most accurate methods of providing location

information (Longley et al, 2005; Trimble, 2002;

Taylor et al, 2001) Organizations that maintain

GIS databases – be theylocal governments or oil

companies – can easily and accurately inventory

either stationary or moving things and add those

locations to their databases (Imran et al, 2006;

Steede-Terry, 2000) Some common applications

of coupling GPS and GIS are surveying, crime

mapping, animal tracking, traffic management,

emergency management, road construction, and

vehicle navigation

bAckground

need for gps data in g Is

When people try to find out where on earth they

are located, they rely on either absolute

coordi-nates with latitude and longitude information or

relative coordinates where location information is

expressed with the help of another location

(Ken-nedy, 2002) GIS maps can be created or corrected

from the features entered in the field using a GPS

receiver (Maantay and Ziegler, 2006) Thus people

can know their actual positions on earth and then

compare their locations in relation to other objects

represented in a GIS map (Thurston et al, 2003;

Kennedy, 2002)

GIS uses mainly two types of datasets: (a)

primary, which is created by the user; and (b)

secondary, which is collected or purchased from

somewhere else In GIS, primary data can be

created by drawing any feature based on given

dimensions, by digitizing ortho-photos, and by

analyzing survey, remote sensing, and GPS data

Using GPS, primary data can be collected curately and quickly with a common reference system without any drawing or digitizing opera-tion Once the primary data is created, it can be distributed to others and be used as secondary data Before using GPS as a primary data collec-tion tool for GIS, the users need to understand the GPS technology and its limitations

ac-The GPS Technology

The GPS data can be collected from a constellation

of active satellites which continuously transmit coded signals to receivers and receive correctional data from monitoring stations GPS receivers process the signals to compute latitude, longitude, and altitude of an object on earth (Giaglis, 2005; Kennedy, 2002)

A method, known as triangulation, is used

to calculate the position of any feature with the known distances from three fixed locations (Le-tham, 2001) However, a discrepancy between satellite and receiver timing of just 1/100th of

a second could make for a misreading of 1,860 miles (Steede-Terry, 2000) Therefore, a signal from a fourth satellite is needed to synchronize the time between the satellites and the receivers (Maantay and Ziegler, 2006; Longley et al, 2005; Letham, 2001) To address this fact, the satellites have been deployed in a pattern that has each one passing over a monitoring station every twelve hours, with at least four visible in the sky all the times (Steede-Terry, 2000)

The United States Navigation Satellite Timing and Ranging GPS (NAVSTAR-GPS) constella-tion has 24 satellites with 3 spares orbiting the earth at an altitude of about 12,600 miles (USNO NAVSTAR GPS, 2006; Longley et al, 2005; Steede-Terry, 2000) The GLONASS consists of 21 satellites in 3 orbital planes, with 3 on-orbit spares (Space and Tech, 2005) The proposed system GALILEO will be based on a constellation of 30 satellites and ground stations (Europa, 2005)



Coupling GPS and GIS

The NAVSTAR-GPS has three basic segments:

(1) the space segment, which consists of the

satel-lites; (2) the control segment, which is a network

of earth-based tracking stations; and (3) the user

segment, which represents the receivers that pick

up signals from the satellites, process the signal

data, and compute the receiver’s location, height,

and time (Maantay and Ziegler, 2006; Lange and

Gilbert, 2005)

Data Limitations and Accuracy Level

Besides the timing discrepancies between the

satellites and the receivers, some other elements

that reduce the accuracy of GPS data are orbit

errors, system errors, the earth’s atmosphere,

and receiver noise (Trimble, 2002; Ramadan,

1998) With better attention to interoperability

between the GPS units, hardware, and software,

some of these errors can be minimized before

the data are used in GIS (Thurston et al, 2003;

Kennedy, 2002)

Using a differential correction process, the

receivers can correct such errors The Differential

GPS (DGPS) uses two receivers, one stationary

and one roving The stationary one, known as

the base station, is placed at a precisely known

geographic point, and the roving one is carried by

the surveyor (Maantay and Ziegler, 2006; Imran

et al, 2006; Thurston et al, 2003; Kennedy, 2002;

Taylor et al, 2001; Steede-Terry, 2000) The base

station sends differential correction signals to the

moving receiver

Prior to 2000, the GPS signal data that was

available for free did not deliver horizontal

po-sitional accuracies better than 100 meters Data

with high degree of accuracy was only available

to U.S government agencies and to some

uni-versities After the U.S Department of Defense

removed the restriction in May 2000, the positional

accuracy of free satellite signal data increased to

15 meters (Maantay and Ziegler, 2006) In

Sep-tember 2002, this accuracy was further increased

to 1 to 2 meters horizontally and 2 to 3 meters

vertically using a Federal Aviation Administration funded system known as Wide Area Augmenta-tion System (WAAS) WAAS is available to thepublic throughout mostof the continental United States (Maantay and Ziegler, 2006)

Depending on the receiver system, the DGPS can deliver positional accuracies of 1 meter or less and is used where high accuracy data is required (Maantay and Ziegler, 2006; Longley et al, 2005; Lange and Gilbert, 2005; Taylor et al, 2001) For example, the surveying professionals now use Carrier Phase Tracking, an application of DGPS, which returns positional accuracies down to as little as 10 centimeters (Maantay and Ziegler, 2006; Lange and Gilbert, 2005)

Integr At Ion of gps And g Is

The coupling of GPS and GIS can be explained

by the following examples:

• A field crew can use a GPS receiver to enter the location of a power line pole in need of repair; show it as a point on a map displayed

on a personal digital assistant (PDA) using software such as ArcPad from ESRI; enter attributes of the pole; and finally transmit this information to a central database (Maantay and Ziegler, 2006)

• A researcher may conduct a groundwater contamination study by collecting the co-ordinates and other attributes of the wells using a GPS; converting the data to GIS; measuring the water samples taken from the wells; and evaluating the water quality parameters (Nas and Berktay, 2006) There are many ways to integrate GPS data

in GIS, ranging from creating new GIS features

in the field, transferring data from GPS ers to GIS, and conducting spatial analysis in the field (Harrington, 2000a) More specifically, the GPS-GIS integration can be done based on the

receiv- 0

following three categories – data-focused

integra-tion, position-focused integraintegra-tion, and

technol-ogy-focused integration (Harrington, 2000a) In

data-focused integration, the GPS system collects

and stores data, and then later, transfers data to

a GIS Again, data from GIS can be uploaded

to GPS for update and maintenance The

posi-tion-focused integration consists of a complete

GPS receiver that supplies a control application

and a field device application operating on the

same device or separate devices In the

technol-ogy-focused integration, there is no need for a

separate application of a device to control the GPS

receiver; the control is archived from any third

party software (Harrington, 2000a)

Figure 1 provides an example of a schematic

workflow process of the GPS-GIS integration by

using Trimble and ArcGIS software In short, the

integration of GPS and GIS is primarily focused

on three areas - data acquisition, data processing

and transfer, and data maintenance

Data Acquisition

Before collecting any data, the user needs to

de-termine what types of GPS techniques and tools

will be required for a particular accuracy

require-ment and budget The user needs to develop or

collect a GIS base data layer with correct spatial

reference to which all new generated data will be

referenced (Lange and Gilbert, 2005)

The scale and datum of the base map are also

important For example, a large-scale base map

should be used as a reference in a site specific

project in order to avoid data inaccuracy While

collecting GPS data in an existing GIS, the datum

designation, the projection and coordinate system

designation, and the measurement units must be

identical (Kennedy, 2002; Steede-Terry, 2000) It

is recommended that all data should be collected

and displayed in the most up-to-date datum

avail-able (Lange and Gilbert, 2005)

The user may create a data dictionary with

the list of features and attributes to be recorded

before going to the field or on-spot If it is created beforehand, the table is then transferred into the GPS data collection system Before going to the field, the user also needs to find out whether the locations that will be targeted for data collection are free from obstructions The receivers need

a clear view of the sky and signals from at least four satellites in order to make reliable position measurement (Lange and Gilbert, 2005; Giaglis, 2005) In the field, the user will check satellite availability and follow the manuals to configure GPS receivers before starting data collection.GIS uses point, line, and polygon features, and the data collection methods for these features are different from one another A point feature (e.g.,

anelectricity transmission pole) requires the user

Figure 1 Example workflow process of GPS-GIS integration



Coupling GPS and GIS

to remain stationary at the location and capture

the information using a GPS device For a line

feature (e.g., aroad), the user needs to record the

positions periodically as s/he moves along the

feature in the real world To capture a polygon

feature (e.g., aparking lot) information, the

posi-tions of the recorder are connected in order to form

a polygon and the last position always connects

back to the first one The user has to decide what

types of features need to be created for a GIS map

In a small scale map, a university campus can be

shown as a point, whereas in a detailed map, even

a drain outlet can be shown as a polygon

GPS coordinates can be displayed in real time

in some GIS software such as ESRI ArcPad,

Intergraph Intelliwhere, and Terra Nova Map

IT In the age of mobile GIS, users can go on

a field trip, collect GPS data, edit, manipulate,

and visualize those data, all in the field While

GPS and GIS are linked, the GPS receiver can

be treated as the cursor of a digitizer It is linked

to the GIS through a software module similar to

a digitizer controller where data are saved into a

GIS filing system (Ramadan, 1998; UN Statistics

Division, 2004) In real-time GPS/GIS integration,

data may be collected and stored immediately for

future use in a mapping application, or data may

be discarded after use in a navigation or tracking

application (Thurston et al, 2003)

For example, Map IT is a new GIS software

designed for digital mapping and GPS data capture

with a tablet PC The software connects a tablet pc

to a GPS antenna via aUSB port While

conduct-ing the field work, the user may use the software

to: (a) display the current ground position on the

tablet PC’s map display in real time; (b) create new

features and add coordinates and other attributes;

(c) edit or post-process the data in real time; and

(d) automatically link all activity recorded in the

field (including photographs, notes, spreadsheets,

and drawings) to the respective geographic

posi-tions (Donatis and Bruciatelli, 2006)

Although the integration of GIS and GPS can

in general increase accuracy and decrease project costs and completiontime, it can also create new problems, including creation of inaccurate data points and missing data points (Imran et al, 2006) Sometimes a handheld GPS navigator may not

be able to acquire a lock on available satellites because of natural conditions like dense forest canopies, or human-made structures like tall buildings or other obstacles (Lange and Gilbert, 2005; Thurston et al, 2003) Data collection with GPS also might get affected by any equipment malfunction in the field

data processing and t ransfer

Once the data are collected, they can be

download-ed, post-processdownload-ed, and exported to GIS format from the field computer to the office computer Where real-time signals are needed but cannot

be received, the post-processing techniques can

be applied to re-process the GPS positions ing this technique, the feature positions can be differentially corrected to the highest level of accuracy The users who integrate GPS data into their own applications need to consider how and when they should apply differential corrections Real-time processing allows recording and correcting a location in seconds or less, but is usually less accurate Post-processing allows the surveyor recording a location as much time

Us-as s/he likes, and then differentially corrects each location back in the office This technique

is used in mapping or surveying (Steede-Terry, 2000; Thurston et al, 2003) Instead of relying

on real-time DGPS alone, the users should enable their applications to record raw GPS data and al-low post-processing techniques to be used either solely or in conjunction with real-time DGPS (Harrington, 2000b)

Most GPS receiver manufacturers have their own data file format GPS data is stored in a receiver in its own format and later can be trans-lated to various GIS formats (Lange and Gilbert,



2005; Ramadan, 1998) Data can be transferred

in a couple of ways One simple way is collecting

coordinates and attributes in a comma delimited

file from the GPS device storage The other more

preferable way is converting the data from GPS

storage to the user-specific database interchange

format using a data translation program (Lange

and Gilbert, 2005) Such a program allows the

user to (1) generate metadata; (2) transform the

coordinates to the projection, coordinate system,

and datum of the user’s choice; and (3) translate

GPS data into customized formats that the GPS

manufacturers could never have anticipated

(Lange and Gilbert, 2005)

A number of file interchange protocols are

available to exchange data between different

brands and types of receivers One widely used

interchange protocol is the Receiver Independent

Exchange Format (RINEX), which is supported

by most satellite data processing software (Yan,

2006) Another commonly used interface standard

is a standard released by the National Marine

Electronics Association (NMEA) Most GPS

receivers support this protocol and can output

NMEA messages, which are available in ASCII

format (Yan, 2006)

data Maintenance

For data revisions or data maintenance, GIS data

is transferred back to the field computer and can

be verified or updated in the field The user can

relocate features via navigation, verify the position

and attribute features, and navigate to locations

to collect new attribute data The user may select

features and examine themin the field, modify

attributes, and even collect new features if desired

Using receivers such as Trimble, any feature that

has been added or updated is automatically marked

to determine which data needs to go back to GIS

(Trimble, 2002)

future trends

The future trends of GIS-GPS integration will

be focused on data accuracy, interoperability, and affordability In order to make the WAAS level of precision available to users worldwide, the Unites States is working on international agreements to share similar technologies avail-able in other parts of the world, namely Japan’s Multi-Functional Satellite Augmentation System (MSAS) and Europe’s Euro Geostationary Navi-gation Overlay Service (EGNOS) (Maantay and Ziegler, 2006) In addition, the European satellite positioning system, Galileo, will be dedicated to civilian activities which will further increase the availability of accurate data to general users New applications of GIS-GPS integration are constantly becoming popular and widespread The latest developments in GPS technology should encourage more use of such integration in the future Reduction in cost and personnel training time of using GPS technology with high data accuracy will eventually provide a cost-effective means of verifying and updating real time GIS mapping in the field (Maantay and Ziegler, 2006;

UN Statistics Division, 2004)

conc Lus Ion

In today’s market, the mobile GIS and GPS devices are available with greater accuracy at a reduced cost The data transfer process from GPS to GIS has become faster and easier GIS software is get-ting more powerful and user friendly, and GPS devices are increasingly getting more accurate and affordable The integration of GIS and GPS has been already proven to be very influential in spatial data management, and it will have steady growth in the future



Coupling GPS and GIS

references

Donatis, M., & Bruciatelli, L (2006) Map IT: The

GIS Software for Field Mapping with Tablet PC

Computers and Geosciences, 32(5), 673-680

Europa web site

http://www.eu.int/comm/dgs/en-ergy_transport/galileo /index_en.htm, accessed

on December 12, 2005

Giaglis, G (2005) Mobile Location Services In

M Khosrow-Pour (Ed.), Encyclopedia of

Infor-mation Science and Technology, 4, 1973-1977

Pennsylvania: Idea Group Reference

Harrington, A (2000a) GIS and GPS:

Technolo-gies that Work Well Together Proceedings in the

ESRI User Conference, San Diego, California.

Harrington, A (2000b) GPS/GIS Integration:

What Can You Do When Real-Time DGPS Doesn’t

Work? GeoWorld, 13(4) Available online at http://

www.geoplace.com/gw/2000/0400/0400int.asp,

accessed on August 25, 2006

Imran, M., Hassan, Y., & Patterson, D (2006)

GPS-GIS-Based Procedure for Tracking Vehicle

Path on Horizontal Alignments Computer-Aided

Civil and Infrastructure Engineering, 21(5),

383-394

Kennedy, M (2002) The Global Positioning

System and GIS: An Introduction New York:

Taylor and Francis

Maantay, J & Ziegler, J (2006) GIS for the Urban

Environment California: ESRI Press, 306-307

Nas, B & Berktay, A (2006) Groundwater

Contamination by Nitrates in the City of Konya,

(Turkey): A GIS Perspective Journal of

Environ-mental Management 79(1), 30-37.

Lange, A & Gilbert, C (2005) Using GPS for

GIS Data Capture In Geographic Information

Systems: Principles, Techniques, Management,

and Applications (pp 467-476) NJ: John Wiley

& Sons, Inc

Letham, L (2001) GPS Made Easy Washington:

The Mountaineers, 5(12), 183-186

Longley, P., Goodchild, M., Maguire, D., & Rhind,

D (2005) Geographic Information Systems and Science New Jersey: John Wiley & Sons, Inc (pp 122-123, 172-173)

Ramadan, K (1998) The Use of GPS for GIS

Applications Proceedings in the Geographic

Information Systems: Information Infrastructures and Interoperability for the 21st Century Informa- tion Society, Czech Republic.

Space and Tech web site dtech.com/spacedata/constellations/glonass_con-sum.shtml, accessed on December 12, 2005

http://www.spacean-Steede-Terry, K (2000) Integrating GIS and

the Global Positioning System California: ESRI

Thurston, J., Poiker, T., & Moore, J (2003)

In-tegrated Geospatial Technologies – A Guide to GPS, GIS, and Data Logging New Jersey: John

Wiley & Sons, Inc

Trimble Navigation Limited (2002) TerraSync Software – Trimble’s Productive Data Collection and Maintenance Tool for Quality GIS Data California: Trimble Navigation Limited

UN Statistics Division (2004) Integration of GPS,

Digital Imagery and GIS with Census Mapping

New York: United Nations Secretariat

USNO NAVSTAR GPS web site http://tycho.usno.navy.mil/gpsinfo.html, accessed on August

26, 2006

Yan, T (2006) GNSS Data Protocols: Choice and

Implementation Proceedings in the International

Global Navigation Satellite Systems Society NSS Symposium, Australia

IG-

key t er Ms

Coordinate System: A reference framework

used to define the positions of points in space in

either two or three dimensions

Datum: The reference specifications of a

measurement system, usually a system of

coor-dinate positions on a surface or heights above or

below a surface

DGPS: The Differential GPS (DGPS) is used

to correct GPS signal data errors, using two

receiv-ers, one stationary (placed at a precisely known

geographic point) and one roving (carried by the

surveyor) The stationary receiver sends

differ-ential correction signals to the roving one

GPS Segment: GPS consists of three

seg-ments: (i) space segment – the GPS satellites, (ii) user segment – the GPS handheld navigator, and (iii) ground control segment – the GPS monitor-ing stations

Projection: A method requiring a

system-atic mathemsystem-atical transformation by which the curved surface of the earth is portrayed on a flat surface

Scale: The ratio between a distance or area

on a map and the corresponding distance or area

on the ground, commonly expressed as a tion or ratio

frac-WAAS: The Wide Area Augmentation System

(WAAS) is a system that can increase the GPS signal data accuracy to 1 to 2 meters horizontally and 2 to 3 meters vertically

National University of Singapore, Singapore

Copyright © 2009, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited.

Navigation systems have been of growing interest

in both industry and academia in recent years The

foundation of navigation systems is based on the concept of utilizing radio time signals sent from some wide-range transmitters to enable mobile receivers to determine their exact geographic

Global Positioning System

The invention of GPS has had a huge influence

on modern navigation systems GPS was oped by the U.S Department of Defense in the mid-1980s Since it became fully functional in

devel-1994, GPS has acted as the backbone of modern navigation systems around the world

The GPS consists of a constellation of 24 ellites in circular orbits at an altitude of 20,200 kilometers (Leick, 1995) Each satellite circles the Earth twice a day Furthermore, there are six orbital planes with four satellites in each plane The orbits were designed so that at least four satellites are always within line-of-sight from most places

sat-on the earth (Langley, 1991) The trajectory of the satellites is measured by five monitoring stations around the world (Ascension Island, Colorado Springs, Diego Garcia, Hawaii, and Kwajalein) The master control station, at Schriever Air Force Base, processes the monitoring informa-tion and updates the onboard atomic clocks and the ephemeris of satellites through monitoring stations (El-Rabbany, 2002)

Each GPS satellite repeatedly broadcasts radio signals traveling by line-of-sight, meaning that they will pass through air but will not penetrate most solid objects GPS signals contain three

location Based on this precise location, mobile

receivers are able to perform location-based

services (Shekhar, et al 2004) With the

avail-ability and accuracy of satellite-based positioning

systems and the growing computational power of

mobile devices, recent research, and commercial

products of navigation systems are focusing on

incorporating real-time information for

support-ing various applications In addition, for routsupport-ing

purposes navigation systems implement many

algorithms related to path finding (e.g., shortest

path search algorithms) An increasing number

of useful applications are implemented based on

these fundamental algorithms

Mo dern nAvIg At Ion syste Ms

A navigation system is an integration of position

and orientation devices, computation devices,

communication hardware and software for

guid-ing the movement of objects (e.g., people, vehicles,

etc.) from one location to another In general,

the infrastructure of navigation systems can be

classified into two subsystems: positioning

sig-nal transmission systems and positioning sigsig-nal

receivers The positioning signal transmission

system allows the signal receiver to determine its

location (longitude, latitude, and altitude) using

timing signals Positioning signal receivers range

from hand-held devices, cellular phones, to

car-based devices These devices typically include

some storage of map data and the computing

capabilities of spatial operations, such as

calculat-ing directions Additionally, in some novel

geo-informatics applications, the receiver also relies

on some server components for various services,

such as real-time traffic information In such a

scenario, a server infrastructure is introduced

which includes a Web server, a spatial database

server, and an application server to provide these

services The signal receiver communicates with



Modern Navigation Systems and Related Spatial Query

pieces of information (Hofmann-Wellenhof et

al, 1994): a pseudo random sequence, ephemeris

data, and almanac data The pseudo random

sequence identifies which satellite is

transmit-ting the signal Ephemeris data allows the GPS

receiver to determine the location of GPS satellites

at any time throughout the day Almanac data

consists of information about the satellite status

and current time from the onboard atomic clock

of the satellite

The GPS receiver calculates its location based

on GPS signals using the principle of trilateration

(Kennedy, 2002) First, the GPS receiver

calcu-lates its distance to a GPS satellite based on the

timing signal transmission delay from the

satel-lite to the receiver multiplied by the speed of

radio signals After measuring its distance to at

least four satellites, the GPS receiver calculates

its current position at the intersection of four

abstract spheres, one around each satellite, with

a radius of the distance from the satellite to the

GPS receiver

GPS Accuracy

As a positioning signal transmission system,

the accuracy of GPS is a very important issue

However, GPS was initially introduced with a

feature called Selective Availability (or SA) that

intentionally degraded the accuracy by

introduc-ing an error of up to 100 meters into the civil

tim-ing signals Improved accuracy was available to

the United States military and a few other users

who were given access to the undegraded timing

signal On May 1, 2000, SA was finally turned

off, resulting in a substantial improvement of the

GPS accuracy (Conley, 2000)

Additionally, the accuracy of GPS can be

af-fected by the atmospheric conditions (e.g.,

Iono-sphere, Troposphere) as well as reflections of the

radio signal off the ground and the surrounding

structures close to a GPS receiver The normal

GPS accuracy is about 30 meters horizontally and

52 meters vertically at the 95% probability level

when the SA option is turned off (Kennedy, 2002) There are several approaches that have been used

to improve the accuracy of GPS

Differential GPS (DGPS) (Kennedy, 2002) uses a network of stationary GPS receivers on the ground acting as static reference points to calculate and transmit correction messages via FM signals

to surrounding GPS receivers in a local area The improved accuracy provided by DGPS is equal to 0.5 m to 1 m near the reference point at the 95% probability level (Monteiro et al 2005) Before the SA option was turned off by the Department

of Defense, DGPS was used by many civilian GPS devices to improve the accuracy

The Wide Area Augmentation System (WAAS) (Loh, Wullschleger et al 1995) has been widely embedded in GPS devices recently WAAS uses

25 ground reference stations across the United States to receive GPS signals and calculate cor-rection messages The correction messages are uploaded to a geosynchronous satellite and then broadcast from the satellite on the same frequency

as GPS to the receivers Currently WAAS only works for North America as of 2006 However, the European Geostationary Navigation Overlay Service (EGNOS) and the Multi-Functional Sat-ellite Augmentation System (MSAS) are being developed in Europe and Japan, respectively They can be regarded as variants of WAAS

The Local Area Augmentation System (LAAS) (United States Department of Transportation, FAA, 2002) uses a similar approach where cor-rection messages are calculated, transmitted, and broadcast via VHF data link within a local area where accurate positioning is needed The transmission range of these correction messages

is typically about a 30 to 50 kilometer radius around the transmitter

g Lon Ass and g alileo positioning System

The GLObal NAvigation Satellite System (Global’naya Navigatsionnaya Sputnikovaya



Sistema, GLONASS) is a satellite-based

position-ing signal transmission system developed by the

Russian government as a counterpart to GPS in

the 1980’s The complete GLONASS consists

of 24 satellites in circular orbits at an altitude

of 19,100 kilometers Each satellite circles the

Earth in approximately 11 hours, 15 minutes

The orbits were designed such that at least five

satellites are always within line-of-sight at any

given time Based on measurements from the

timing signal of four satellites simultaneously,

the system is able to offer location information

with an accuracy of 70 meters

There were 17 satellites in operation by

December 2005 offering limited usage With

the participation of the Indian government, it is

expected that the system will be fully operational

with all 24 satellites by 2010

GALILEO (Issle et al 2003) is being developed

by the European Union as an alternative to GPS

and GLONASS GALILEO is intended to provide

positioning signals with a precision higher than

GPS to both civil and military users Moreover, it

improves the coverage of satellite signals at high

latitude areas The constellation of GALILEO

con-sists of 30 satellites in circular orbits at an altitude

of 23,222 kilometers The GALILEO system is

expected to be fully operational by 2010

positioning signal r eceivers

Most positioning signal receiving devices are

designed for the use with the GPS system These

devices have been manufactured in a wide variety

for different purposes, from devices integrated

into cars, personal digital assistants, and phones,

to dedicated devices such as hand-held GPS

receivers The most popular variants are used in

car-based navigation systems that visualize the

position information calculated from GPS signals

to locate an automobile on a road retrieved from

a map database

In these car-based systems, the map database usually consists of vector information of some area of interest Streets and points of interest are encoded and stored as geographic coordinates The client is able to find some desired places through searching by address, name, or geographic coordinates The map database is usually stored

on some removable media, such as a CD or flash memory A common approach is to have a base map permanently stored in the ROM of GPS de-vices Additional detailed information of areas of interest can be downloaded from a CD or online

by the user in the future

Integrating the positioning data from a GPS receiver with the Geographic Information Sys-tem (GIS) involves data retrieval, data format transformation, multi-layer data display, and data processing With GPS, it is possible to col-lect the positioning data in either the real-time or post-processed mode The digital format of GPS data is then converted into a compatible format used in the GIS applications (Steede-Terry 2000; Kennedy, 2002) Together with other spatially referenced data (e.g., the digital road map data), the GIS application consists of a collection of layers that can be analyzed for a wide variety of purposes, such as calculating the route from the current position to a destination

nAvIg At Ion r eLAted spAt IAL Quer y ALgor Ith Ms

As mentioned earlier, many location-based end-user applications can be provided after a positioning signal receiver calculates the posi-tion of a user There are several spatial query algorithms which are commonly utilized by modern positioning signal receivers (e.g., GPS devices) for supporting location-based services and shortest path routing We broadly categorize them into location-based query algorithms and shortest path search algorithms in this section



Modern Navigation Systems and Related Spatial Query

Table 1 summarizes the symbolic notations used

throughout this section

Location-Based Query Algorithms

Point Query The term point query (PQ) can

be defined as: given a query point q, find all the

spatial objects O which contain q.

PQ( q ) { O| o i O,q o } i

The query processing efficiency of a point query

can be improved by utilizing spatial indices, e.g.,

the R-tree (Guttman, 1984) or the Quadtree (Samet,

1984) With a spatial index, all the spatial objects

are represented by geometric approximations such

as an MBR (Minimum Bounding Rectangle)

Consequently, determining whether the query

point is in an MBR is less expensive than

check-ing if the query point is in an irregular polygon

After retrieving all the MBRs which overlap with

the query point as candidates, the exact geometry

of each element in the candidate set is examined

Point queries can be applied to determine the

overlapping regions (e.g., administrative divisions)

of navigation system users

Nearest Neighbor Query The term nearest

neighbor query (NNQ) can be defined as: given

a query point q and a set of spatial objects O, find

the spatial object o i∈ O which has the shortest

distance to q

NNQ( q ) { o | o i j O,dist( q,o ) dist( q,o )} i j

R-trees and their derivatives (Sellis et al 1987; Beckmann et al 1990) have been a prevalent method to index spatial data and increase query performance To find nearest neighbors, branch-and-bound algorithms have been designed that search an R-tree in either a depth-first (Rousso-poulos et al 1995) or best-first manner (Hjaltason

& Samet, 1999) to detect and filter out unqualified branches Both types of algorithms were designed for stationary objects and query points They may

be used when moving objects infrequently pose nearest neighbor queries

Range Query The term range query (RQ) can

be defined as: given a query polygon q and a set

of spatial objects O, find all the spatial objects in

O which intersect with q.

Range queries can be solved in a top-down sive procedure utilizing spatial index structures (e.g., the R-tree) The query region is examined first against each branch (MBR) from the root

recur-If the query polygon overlaps with any branch, the search algorithm is employed recursively

on sub-entries This process terminates after it reaches the leaf nodes of the index structure The selected entries in the leaves are used to retrieve the records associated with the selected spatial keys (Shekhar et al 2004)

shortest path search Algorithms

Dijkstra’s Algorithm One important function

of navigation systems is to find the shortest route

to a user specified destination The well-known Dijkstra’s algorithm (Dijkstra, 1959) provides an ideal solution for finding single-source shortest paths in a graph of vertices connected through edges We present the algorithm, assuming that there is a path from the vertex of interest to each

of the other vertices It is a simple tion to handle the case where this is not so We

modifica-initialize a set of vertices D to contain only the

Table 1 Symbolic notation

The location of a query point

A set of spatial objects

The Euclidean distance between two objects a and b

A set of nodes

A set of edges

 0

node whose shortest paths are to be determined

and assume the vertex of interest is v 1 We also

initialize a set E of edges to being empty First

we choose a vertex v i that is closest to v 1 and add

it to D In addition, we also add the edge < v 1 , v i

> to E That edge is clearly a shortest path from

v 1 to v i Then we check the paths from v 1 to the

remaining vertices that allow only vertices in D

as intermediate vertices A shortest of these paths

is a shortest path The vertex at the end of such a

path is added to D and the edge that touches that

vertex is added to E This procedure is continued

until D covers all the vertices At this point, E

contains the edges for the shortest paths

(Nea-politan & Naimipour, 1998)

Adaptive Shortest Path Search Algorithm

Most existing shortest path searching algorithms

are executed based on static distance

informa-tion: pre-defined road segments with fixed road

conditions are used in the computation However

any real-time events (e.g., detours, traffic

conges-tions, etc.) affecting the spatial network cannot

be reflected in the query result For example, a

traffic jam occurring on the route to the computed

destination most likely elongates the total driving

time More drastically, the closure of a restaurant

which was found as the destination according to

its network distance might even invalidate a query

result In other words, finding the shortest path in

terms of travel time is more important than the

actual distance Therefore, we need adaptive

short-est path search algorithms which can integrate

real-time events into the search/routing procedure

Ku et al (Ku et al 2005) proposed a novel travel

time network that integrates both road network

and real-time traffic event information Based on

this foundation of the travel time network, they

developed an adaptive shortest path search

algo-rithm that utilizes real-time traffic information

to provide adaptive shortest path search results

This novel technique could be implemented in

future navigation systems

c onc Lus Ion

We have presented the foundation and state of the art development of navigation systems and reviewed several spatial query related algorithms GPS has been increasingly used in both military and civilian applications It can be forecast that GPS will be extensively used and its applicability expanded into new areas of applications in the future Meanwhile, additional civilian frequencies will be developed and allocated to ease the conges-tion of civil usage GPS developers are anticipating the advent of the European GALILEO system that will introduce the birth of the Global Navigation Satellite System (GNSS) infrastructure, which combines the functionality of GPS and GALILEO together (Gibbons 2004) The interoperation of GPS and GALILEO will benefit the users with more signal availability, more signal power, and improved signal redundancy around the world

In addition, several websites (e.g., MapQuest, Yahoo! Maps, etc.) have integrated shortest path search algorithms into on-line services Users can conveniently search the shortest path to their destinations by utilizing these services

Acknow Ledg Ment

This article was made possible by the NSF grants ERC Cooperative Agreement No EEC-9529152, CMS-0219463 (ITR), and IIS-0534761 Any opinions, findings and conclusions or recom-mendations expressed in this material are those

of the authors and do not necessarily reflect those

of the National Science Foundation

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key t er Ms

Ephemeris: Refers to the relative positions

of the planets, or satellites in the sky at a given moment



Geosynchronous Satellite: A satellite whose

orbital track lies over the equator

GIS: A system for creating, integrating,

ana-lyzing and storing managing geographical data

and associated features In general, GIS provides

users with an interface to query, retrieve, and edit

the spatial data in an efficient way

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least cost path through an underlay network

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posi-tions of an object using the geometry of sphere intersections To accurately determine the relative position of an object in 2D, trilateration uses at least 3 reference points, and the measured distance between the object and each reference point

293

Chapter XXXVII

Location Privacy in Automotive

Telematics

Muhammad Usman Iqbal

University of New South Wales, Australia

Samsung Lim

University of New South Wales, Australia

Copyright © 2009, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited.

Abstr Act

Over the past few decades, the technologies of mobile communication, positioning, and computing have gradually converged The automobile has been a natural platform for this convergence where satellite- based positioning, wireless communication and on-board computing work in tandem offering various services to motorists While there are many opportunities with these novel services, signi.cant risks to the location privacy of motorists also exist as a result of the fast-paced technological evolution These risks must be confronted if trust and confidence are to prevail between motorists and service providers This chapter provides an overview of the current situation of location privacy in automotive telematics

by exploring possible abuses and existing approaches to curb these abuses followed by a discussion of possible privacy-strengthening measures



The proliferation of location-aware computing

devices promises an array of “quality-of-life

enhancing” applications These services include

in-car navigation, roadside assistance,

infotain-ment, emergency response services, vehicle

diagnostics and prognostics The key idea is to

provide services using “location” as a geographic

filter These services can be triggered by an event,

for example, the location of the vehicle can be

transmitted to an emergency response center on

deployment of air bags Some services can be

explicitly requested by the driver, for example,

in-car navigation or road side assistance While

other applications can be quietly running at all

times, passing on real-time information of the

vehicle’s movements such as Global Positioning

System (GPS) enabled Pay-As-You-Drive (PAYD)

insurance (Grush, 2005)

Although location data is critical to the

opera-tion of such applicaopera-tions, there is a precarious

balance between the necessary dissemination of

location information and the potential for abuse

of this private information Spatio-temporal

(loca-tion in time) informa(loca-tion continuously monitored

(and logged) about the places a person visits can

reveal a lot about one’s persona Given the current

capabilities of inference by combining disparate

sources of information, a lot can be inferred about

an individual These derived profiles can then

be used to make judgments about a person or

used for unsolicited marketing by location-based

marketers Orwell (1949), in his criticism against

totalitarianism, would have most likely referred

to these “Small Brothers” (location-based retail

marketers) had he known about these inference

attacks

In the next few sections a background on

loca-tion privacy is presented, some possible privacy

abuses of telematics services are discussed, and

existing approaches to curb these abuses are

investigated The chapter then suggests possible measures to strengthen location privacy

bAckground

Before delving into the core issue of location privacy, it is important to agree on a definition of privacy itself Much of the literature pertaining

to privacy refers to Westin’s precise definition

In the context of telematics, location privacy is a special case of privacy, relating to the privacy of location information of the vehicle, and ultimately the user of the vehicle

Privacy is the claim of individuals, groups and institutions to determine for themselves, when, how and to what extent information about them

is communicated to others (Westin, 1967)

How Positioning Systems can be Privacy Invasive?

Positioning systems can be categorized into either being ‘Self-positioning’ or ‘Remote-positioning’

In Self-positioning systems, the vehicle is either fitted with a GPS receiver or Dead-Reckoning system (based on one or more gyroscopes, a compass and odometer) to locate where it is on the road Remote-positioning systems require

a central site to determine the location of the vehicle (Drane and Rizos, 1997) The result is

a set of coordinates (or position) of the vehicle expressed in relation to a reference frame or da-tum Self-positioning systems inherently protect location privacy because they do not report the location of the vehicle to any other system On the other hand, remote-positioning systems track, compute and retain the location information at the central monitoring site and creates a risk to the individual’s privacy Self-positioning systems also pose a privacy risk if they report the vehicle’s



Location Privacy in Automotive Telematics

GPS-derived location to a server through the

communications infrastructure

pr IvAcy Att Acks

ACME Rent a Car Company

Most readers would be familiar with the highly

publicized abuse of GPS technology where

ACME charged its customers $150 for speeding

occurrences of more than 80mph A customer

took ACME to court and won on grounds that

the company failed to clearly explain how the

location tracking system would be used (Ayres

and Nalebuff, 2001) This is an obvious scenario

of how personal information can be exploited It

is not unreasonable to imagine that an ordinary

car trip can become an Orwellian ordeal when

one’s location information can be used in ways

not imagined

Location-based spam

Figure 1 illustrates a possible threat scenario where a vehicle is equipped with an on-board GPS receiver and the vehicle periodically transmits its location data to a tracking server The tracking server is connected to various service providers which have been authorized by the driver to ac-cess location data in order to provide telematics services The service providers are not necessarily trusted and it is not unreasonable to expect loca-tion information of individuals being sold on the market (much like email address lists)

Profiling Driving Behavior

Greaves and De Gruyter (2002) discuss how a driving profile of a person can be derived from GPS track data They sought an understanding

of driving behaviors in real-world scenarios by fitting low-cost GPS receivers to vehicles, and logging the vehicle movements Consequently,

Figure 1 A typical privacy threat scenario

P eriodically report location

B uy or access vehicle pos ition data



they were able to identify driving styles from

this data Imagine a PAYD insurance provider

accessing this information, in order to identify an

individual with an ‘aggressive’ driving style

electronic t oll c ollection

Electronic toll collection seeks to alleviate traffic

congestion at toll gates, and provides a convenient

method for drivers to pay tolls Such schemes

typically require the car to have an electronic tag

attached to the front windscreen Tolls are

de-ducted from the vehicle’s account when the

scan-ner senses the toll tag Electronic toll can become

privacy invasive, for example, if the toll system

passes the entry and exit times of the vehicle to

law enforcement agencies giving them the ability

to issue speeding tickets if the distance is traveled

in too short a time (Langheinrich, 2005)

pr IvAcy defen ses

In the previous section location privacy threats

provoking some serious ambivalence about the

social and ethical telematics issues were discussed

There are some countermeasures that can be

taken The first and most simple one would be an

opt-out approach This would result in a denial

of service for the vehicle driver The more

chal-lenging issue is how to preserve location privacy

while at the same time maximizing the benefits

of telematics services

Legislation and Regulation

Location privacy can be considered to be a special

case of information privacy However, because

this area of the law is in its embryonic stages,

one can consider ‘location’ and ‘information’ as

being synonymous

In the United States, legislation to protect

location information arises primarily from the

Telecommunications Act of 1996 and the 1998 E911 amendments As a result, there is ambiguity about the so-called “opt-in” or “opt-out” approach for customer consent However, a bill specifi-cally addressing location privacy, the Wireless Location Privacy Protection Act of 2005, which required location-based services (LBSs)to give their informed consent for disclosure of location information, was referred to the U.S Senate (Ackerman et al, 2003)

In Australia, the Privacy Act of 1988 (“Privacy Act 1988 (Commonwealth)”, 2005) deals with con-sumers’ privacy Besides legislation, Standards Australia has published a guideline suggesting procedures for toll operators and electronic park-ing operators to protect the personal privacy of their customers (Standards-Australia, 2000) Japan and the European Union have well es-tablished laws for protecting consumers’ location privacy (Ackerman et al, 2003) One issue that should be emphasized is that legislation is not the only defense against (location) privacy attacks The corporate world is very good at obscuring questionable practices with fine print in a ser-vice agreement or contract (Schilit et al, 2003) Therefore there has to be enforcement of laws as well as open audit of privacy practices

Policy-Based and Rule-Based protection

Privacy protection regulation concludes that “user consent” is an essential requirement If the growth

in telematics services proceeds as predicted, then

it would be difficult for a member of the public to keep track of all details Secondly, constant explicit consent requirements can become a source of driver distraction Hence an analogy can be drawn from the internet, where the Platform for Privacy Preferences (P3P) is used to manage web server privacy policies in Extensible Markup Language (XML) machine readable format Typically these



Location Privacy in Automotive Telematics

operate by comparing user profile rules of a web

client with the rules on a particular web server

Such is the importance of location privacy that

there are already efforts to extend the P3P for

location rules (Morris, 2002) This means that

rules like “Allow Alice to access my location

on a weekday” can be created Duri et al (2002)

proposed an end-to-end framework based on

a similar principle that provides both security

and privacy within the telematics environment

There is one problem with these implementations,

since the policies serve as a mutual contract; the

driver has to trust the organization to abide by

the policies

The Internet Engineering Task Force (IETF),

the standards body responsible for developing

in-ternet standards, has also realized the importance

of location privacy It has proposed the

Geographi-cal Location/Privacy Charter, referred to simply as

geopriv This standard seeks to preserve location

privacy of mobile internet hosts (IETF, 2006)

Synnes et al (2003) have implemented secure

location privacy, using a similar approach of using

rules to implement policies In the near future, it is

not hard to imagine automobiles having Internet

Protocol (IP) addresses and ultimately using the

geopriv solution to implement privacy policies

Identity and Location Decoupling

One conclusion that can be drawn is that the

vehicle can be uniquely identified when it

com-municates with a particular Telematics Service

Provider (TSP) Therefore, decoupling of identity

and vehicle location is essential at retention of

data This can be regulated through policy, and

laws such as discussed above Herborn et al (2005)

have studied this concept in pervasive

comput-ing networks They argue that decouplcomput-ing these

data from each other would have more benefits

Name ‘hijacking’ would simply not be possible

The issue here is that for decoupling the identity

and other data to work, a robust scheme to resolve

naming would be required This, however, is still

an open research issue

Anonymous Access

Researchers in the field of LBSs have looked at anonymous solutions to location privacy The basic idea here is to access the services anony-mously Unfortunately, this cannot be regarded

as a complete solution given the inference pabilities of Geographical Information Systems (GIS) and advanced surveillance techniques, as discussed already (Gruteser and Hoh, 2005) An adversary can apply data-matching techniques

ca-to independent samples of anonymous data lected, and map them on predictable paths such

col-as roads, and infer the identity of an individual based on where one is

Drawing from techniques used by census boards and electoral commissions to obscure data so that individuals are not identified, another methodology similar to anonymous access has been proposed It is called “k-anonymous access” This means that when the location information of

a subject is requested, it will only be responded to

if there are k other nodes present in the vicinity

(Gruteser and Grunwald, 2003) This approach can give good protection against privacy attacks if

the value of k is set to a high number, however this

would affect the quality of LBSs In this approach,

k is a variable that could only be altered globally

A second approach deals with k on a per node

basis This means that each user can specify his

or her privacy variable (Gedik & Liu, 2005) This approach appears to more realistically simulate user privacy preferences in the real world.Apart from being identified through map-matching techniques, there is one additional problem that can affect the correct operation of telematics services using anonymous techniques Existing approaches discussed here are aimed

at solving the location privacy problem in the



context of LBSs Telematics can be considered to

be a special case of LBSs, the authors, however,

argue that it needs a totally different mindset

for addressing privacy problems of the mobile

public mainly because of differences such as

higher average speeds, predictable paths, and the

magnanimity of the number of users

Obfuscation

The term “obfuscation” means the process of

confusing or obscuring It has been identified as

one possible approach to protect location privacy

in location-aware computing (Duckham and

Kulik, 2005) This deliberate degradation of

loca-tion informaloca-tion is performed by the individual,

through deciding which service would require

what ‘granularity’ of information, often referred

to as the “need to know principle” Snekkenes

(2001) constructed rules for implementing privacy

policies using this principle He emphasized

that different services require different

resolu-tions, or accuracy, of location information The

advantage of obfuscation over anonymity is that

it allows authentication and customization of the

services However, it still is not the ideal remedy

when high accuracy of reported location, instead

of deliberate degradation, is required

Privacy Aware Designs

While defenses discussed above propose measures

for limiting disclosure of location information,

others have sought to understand privacy aware

designs The success of future LBSs depends on

designing systems with privacy in mind, not just

it being an “afterthought” Langheinrich (2005)

discuss the need for anonymous location

infra-structures and transparency protocols allowing

customers to understand and track how their data

is collected and used Kobsa and Telztrow (2006)

argue that clearly explaining privacy policies at

subscription would encourage users to disclose

information and create a sense of trust They conducted experiments to prove this comparing their privacy friendly systems to the traditional data collection systems

Other examples of privacy aware designs include work by Coroama and Langheinrich (2006) where they implemented a GPS based PAYD insurance system depicting real-time risk assessment of actual road conditions Their system calculates premiums on board the vehicle guaranteeing privacy of owners There is periodic transmission of aggregated information to the in-surance provider for bill generation Iqbal and Lim (2006) extended this idea further and proposed a GPS-based insurance product that preserves loca-tion privacy by computing distances traveled on the onboard unit They additionally safeguarded

“spend privacy” by proposing smart card based anonymous payment systems Their approach was

to redesign a closed system curtailing redundant exchange of location data

conc Lus Ion

Location privacy protection in telematics is deed a social issue The authors have reviewed

in-in this short article location privacy threats and possible countermeasures Each countermeasure

to protect privacy has its own implications, and

it is clear that no general panacea exists This suggests that a combination of several different approaches may be the best solution

The reader might feel that the authors have taken a pessimistic view of privacy issues It is acknowledged that location disclosure would be necessary in life threatening scenarios, or where law enforcement officials need access to this in-formation This critical information, however, like other worthwhile liberties needs to be protected by law Under normal circumstances, only the loca-tion information subject has the right to exercise control of one’s personal information



Location Privacy in Automotive Telematics

Development in telematics is through a

coop-eration of companies that are involved in transport

management, vehicle manufacture or information

technology services The current approach

recog-nizes privacy to be a “non-technical barrier” to

the implementation of ITS

(US-Department-of-Transportation, 1997) Since research in transport

telematics is in its nascent stages, it is important

to understand that these issues are not merely

social hindrances Once such scenarios become

commonplace, the general user may be reluctant

to use these telematics services at all Therefore,

it is important to dispel these privacy concerns

right from the beginning, and focus on “building

in” privacy protection within such systems so that

as new applications become available, appropriate

privacy measures are integral to them

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key ter Ms

Context Aware Computing: The process of

customization of software and services to user preferences The computing mechanism changes based on the context, in telematics perspective, location is a context for customization

Electronic Tolls: Electronic payment systems

designed to identify an electronic tag mounted on

a vehicle to deduct the toll charges electronically from the vehicle owner’s account

In-Car Navigation: Usually a voice-activated

system with a liquid crystal display (LCD) screen displaying maps and a combination of on-board GPS receivers, accelerometers, compass and gy-roscopes for positioning the vehicle on the map

Intelligent Transportation Systems: Tools,

software, hardware and services designed for the efficient movement of road transportation and provision of travel information to the vehicles

Location Privacy: Location privacy is the

ability of an individual to control access to his/her current and past location information

0

Location Privacy in Automotive Telematics

Obfuscation: Obfuscation is the deliberate

degradation of location information by

respond-ing in a less granular fashion about requested

location data

Telematics Service Provider: Telematics

Service providers offer services to vehicle

driv-ers for either a subscription fee or any other

arrangement These can be emergency services

or informational services to improve the driving experience

Vehicle Prognostics: Factory installed

sys-tems monitoring and reporting health of vehicle equipment to owner and manufacturer periodi-cally