User's Manual

UtiliNet® Endpoint User Guide 1-5-2007
Page 20 of 30
© Cellnet 2005
Repeatability of the GPS information has proven to be less than ideal. Readings taken from the same
physical location at different times of the day tend to vary significantly (often more than the specified +/-
300 meters). As mentioned earlier, it is most important that the radios’ lat/long coordinates be
RELATIVELY correct to one another. Using a GPS may compromise the repeatability of relatively correct
readings. The user may want to occasionally verify the GPS.
• When using a GPS it is necessary to physically visit each site in order to derive the lat/long coordinates. It
may be desirable to pre-program the radios before they are taken to the site to be installed. This would
require two trips to the site.
• Logistically speaking, only those with the GPS have the ability to derive lat/long coordinates. Efficient
network deployment and maintenance could be compromised or limited by the availability of the GPS.
United States Geological Survey Maps - USGS Maps
USGS maps are readily available from local maps stores, through mail order, and from USGS directly.
Each map section has lat/long coordinates printed along the borders of the map. When considering the use
of a USGS map for constructing and maintaining a UtiliNet network, here are some issues to evaluate:
• Because all USGS maps have a central reference, all derived lat/long coordinates will always be relatively
correct to one another. As mentioned earlier, this is important when considering UtiliNet’s logical routing
algorithms.
• In addition to the geographical information, USGS maps provide topological information that is helpful
when planning and maintaining a UtiliNet network. If the network is installed in an area with high ridges
and low valleys, USGS maps can be used to determine potential trouble areas as well as ideal repeater
sites.
• Maps also provide an excellent graphical representation of the network. If a radio is programmed with the
incorrect lat/long it can easily be identified in a graphical way.
For mail order USGS maps contact:
Map Link, Inc.
30 S. La Patera Lane, Unit #5
Santa Barbara, California 93117
Phone: [phone]
Toll-free phone: [phone]
Fax: [phone]
Toll-free fax: [phone]
U.S.G.S. Topo Dept. Fax: [phone]
Web: http://www.maplink.com
E-Mail: [e-mail]
MapInfo
MapInfo® is a desktop software application that allows the user to graphically view city, county and state
maps on a computer screen. Latitude and longitude coordinates can be derived by simply positioning a
mouse cursor over the intended installation location. The approximate cost for the MapInfo application and
associated map data is $2000. When considering the use of a MapInfo for constructing and maintaining a
UtiliNet network, here are some issues to evaluate:
• MapInfo has software hooks which allow it to connect to a database server. System integrators can use
this feature to store specific installation information about many different networks. In addition to the
lat/long information, the user can store other information such as a description of the site, the installation
date, or the type of installation.
• MapInfo software can run on a laptop computer for field applications. When installing a UtiliNet radio, it
may be easier, depending on the deployment technique, for field personnel to program radios while on site.
With MapInfo, users can derive actual lat/long coordinates and program the radio while in the field.