Geolocation and Standards

1
Geolocation and Standards

• A Look at the Current State of Wayfinding

2
Conditions for Location Awareness
The widespread adoption of location-aware
services will depend upon the existence of three
conditions memory, connectivity, and standards.
memory
connectivity
standards
3
Present State Two Out of Three
At the moment we're close to the state of
convergence, or networked geospatial
intelligence. Most mobile devices have adequate
memory and their connection to the net is
sufficient .The missing link is standards.
memory
connectivity
4
How Devices are Found
5
Method 1 You Tell Us
For the current crop of mobile devices, there are
three basic location finding schemes. The first
is by far the simplest, and the most widely used
at the moment. That is having the user -- the
human agent -- identify the location. Often the
user will be asked for a street address or a ZIP
code to retrieve information about a given
location. This method is accurate so long as the
user knows where he is.
6
Method 2 Cellnet Location
Every cell tower has the unique ID. When it is
communicating with a mobile device, which also
has a unique ID, that device can be placed within
the tower's sphere of communication. Many 911
systems operate this way. A more accurate
method of determining location is cell tower
triangulation. This spotting system uses three
or more cell towers and by measuring signal
strength relative to each tower, places the
device at the intersection point of those spheres
of communication.
7
Method 3 GPS
The third and most accurate method of determining
location is GPS, or Global Positioning Systems .

• GPS depends upon a constellation of 24
  medium-orbit satellites that transmit microwave
  signals back to earth.
• The primary GPS in use is NAVSTAR, which is
  funded by the US Department of Defense and
  maintained by the Air Force

8
How GPS Works

• A GPS receiver calculates its position by
  measuring the distance between itself and three
  or more GPS satellites. By determining the
  position of -- and distance to -- at least three
  satellites, the receiver can compute its position
  using trilateration.
• With a fix on a fourth satellite, GPS receivers
  can also determine elevation above sea level.

9
Latitude and Longitude

• To measure location on the surface of the earth,
  global positioning systems use the
  well-established standard of latitude and
  longitude.
• The concept of latitude was understood by ancient
  sailors and by the 16th century latitude could be
  accurately measured with tools such as the
  backstaff or the sextant.
• It wasnt until the middle of the 18th century
  that longitude could be figured accurately by
  measuring time differences between a ships
  chronograph and time at the prime meridian in
  Greenwich, England.

10
Reading Coordinates

• The location of Razorfishs office at 1440
  Broadway is described in latitude and longitude
  as N4045.267 W7359.178.

This means that we are located at 40 degrees, 45
minutes, and 27 seconds north of the equator and
73 degrees, 59 minutes and 18 seconds west of the
meridian passing through Greenwich, England.
11
GPS Limitations

• Although accurate to within a few meters, GPS
  requires a clear view of a wide swath of sky.
  Tall buildings, dense undergrowth, even solar
  flares can interfere with GPS reception.

12
How Devices Share Information
13
Information Sharing

• While the problem of location finding is mostly
  solved, the issue of information sharing is not.
  There are competing standards in both
  communication networks and information networks
  that prevent location-aware devices from becoming
  a truly global phenomenon.
• Most cell phones in the United States run on a
  CDMA (Code Division Multiple Access) network
  while most mobile phones in the rest of the world
  use GSM (Global System for Mobile
  communications). These two networks are not
  compatible.

CDMA
GSM
14
No Standard Format

• In a similar fashion, geospatial information is
  stored and communicated with a multitude of
  different standards.
• For example, Maptech and Garmin, two of the
  leading location-finding companies, record and
  transmit geospatial data in differing proprietary
  formats. Likewise, scientists working with
  bathymetric, orthographic and geodetic data have
  been using divergent content models to record
  their location-specific information.

EXIF
GDA94
ID3
15
Moving Toward Standards

• This Babel of languages and content models is
  slowly moving toward interoperability and mutual
  intelligibility. The United States Geological
  Survey along with the International Standards
  Organization has endorsed SDTS, the Spatial Data
  Transfer Standard, and there are business groups
  like the OGC, or Open Geospatial Consortium
  advocating a standardized interchange of geodata
  in GML (a subset of XML), while the W3C has a
  working group devoted to semantic
  interoperability.

16
SGML and Its Children

• Perhaps the best bet for interoperability will
  come from the 20-year old standard ISO8879, which
  described SGML, or the Standard Generalized
  Markup Language.
• On the web, XML (eXtensible Markup Language,
  which is a subset of SGML) has gained currency.
  XML is the basis for popular web services like
  those offered by Amazon and Yahoo, and it has
  spawned a host of specialized namespaces and
  schemas to handle geospatial information.
• The best known of these geodescriptive
  metalanguages is KML, or keyhole markup language.
  KML is a version of XML that was developed by the
  Keyhole Corp., which Google bought in 2002 to
  build what is now Google Earth.

17
Convergence? Not Yet.

• Widespread adoption of these new tools and the
  shift to standards-based interoperability will
  depend upon a really compelling economic driver,
  or a must-have application.
• So far no such application has emerged to usher
  in the era of fluent intercommunication.
• It seems, however, that it will just be a matter
  of time.

18
Contact

• Rob Cummings,
• Senior Information Architect,
• Avenue A-Razorfish, 1440 Broadway, New York, NY
  10018
• 212.798.6600
• Also
• Rob Cummings,
• Director,
• Greenpoint Design,
• 1125 Lorimer St., Brooklyn, NY 11222
• 347.581.6359
• www.greenpointdesign.com

19
Bibliography and References
20
References

• Articles
• Do-It-Yourself Cartography, NYTimes.com,
  12/11/2005 http//www.nytimes.com/2005/12/11/maga
  zine/11ideas1-13.html?ex1291957200en1502e0b4ee2
  5c734ei5090...
• Google Zooms In Too Close for Some,
  NYTimes.com, 6/1/2007 http//www.nytimes.com/2007
  /06/01/technology/01private.html?ex1338350400en
  b7678075a3c97d28ei5124
• With Tools on Web, Amateurs Reshape Mapmaking,
  NYTimes.com, 7/27/07, http//www.nytimes.com/2007/
  07/27/technology/27maps.html?ex1187928000ena8b1
  34a3a2aba9a0ei5070
• France Launches Maps Site, WIRED.com,
  6/26/2006, http//www.wired.com/techbiz/it/news/20
  06/06/71234
• Google Maps Is Changing the Way We See the
  World, WIRED.com, 6/26/2007, http//www.wired.com/
  techbiz/it/magazine/15-07/ff_maps?currentPageall
• Mapping out a pathway to success, AM NY,
  8/20/2007, http//www.amny.com/business/am-farn082
  0,0,2549876.story
• Books
• How Maps Work, Alan M. MacEachern,
  http//www.amazon.com/How-Maps-Work-Representation
  -Visualization/dp/157230040X/refpd_bbs_sr_2/002-1
  469296-8338434?ieUTF8sbooksqid1187817394sr1
  -2
• The Power of Maps, Denis Wood,
  http//www.amazon.com/Power-Maps-Denis-Wood/dp/089
  8624932/refpd_bbs_2/002-1469296-8338434?ieUTF8s
  booksqid1187817427sr1-2
• How to Lie with Maps, Mark Monmonier,
  http//www.amazon.com/How-Lie-Maps-Mark-Monmonier/
  dp/0226534219/refpd_bbs_sr_1/002-1469296-8338434?
  ieUTF8sbooksqid1187817458sr1-1
• Mapping sites
• Maps.google.com
• Maps.live.com
• Maps.yahoo.com
• Mapquest.com

21
References Continued ...

• The United States Geological Survey
  (http//www.usgs.gov/ )
• International Standards Organization
  (http//www.iso.org/iso/en/ISOOnline.frontpage
• OGC, or Open Geospatial Consortium
  (http//www.opengeospatial.org/ogc )
• W3C working group devoted to semantic
  interoperability (http//www.w3.org/2005/Incubator
  /mmsem/wiki/FrontPage )
• Library of Congress, Maps -- http//memory.loc.gov
  /ammem/gmdhtml/gmdhome.html
• NASAs Worldwind geobrowser http//worldwind.arc.
  nasa.gov/
• The Map Room blog - http//www.mcwetboy.net/maproo
  m/
• Adam Greenfields blog (Everyware)-
  http//v-2.org/index.php
• GPS Visualizer, map your tracks -
  http//www.gpsvisualizer.com/
• MAKE, track your friends - http//www.makezine.com
  /blog/archive/2005/10/diy_gps_tracking.html
• National Atlas, for Lat-Lon info -
  http//nationalatlas.gov/articles/mapping/a_latlon
  g.html
• New York Times, July 19, 2007. Basics, Global
  Positioning by Cellphone. By LARRY MAGID
• GPS on How Stuff Works - http//electronics.howstu
  ffworks.com/gps-phone.htm
• How Stuff Works, Location Tracking -
  http//people.howstuffworks.com/location-tracking.
  htm
• NYT, June 10, 2007 Practical Traveler Sharing
  Photographs Online Snapshots That Do More Than
  Bore Friends By MICHELLE HIGGINS
• PC Today, Luxury GPS, April 2007
  www.pctoday.com
• Wired Magazine, July 2007, The Whole Earth
  Cataloged - http//www.wired.com/techbiz/it/magazi
  ne/15-07/ff_maps
• The Space-Age Sailor, Good Old Boat, July-August
  2007, www.goodoldboat.com