GPS Handhelds

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GPS Handhelds Powered By Docstoc
					GPS Handhelds



   Erin Miller
  Suzette Stone
                    Introduction
• At one time all GPS units attempted to cater to everyone.
• Currently more specialized units are available.
• You need to understand exactly what you intend to do with
  a GPS unit before you buy one.
• It is a good idea to explore a few features beyond the
  basics.
• Today we are focusing on lower-end GPS handhelds with
  an accuracy generally less than 15 m. These can be used
  for outdoor recreation, navigation, the marking of
  landmarks or other points, but not for survey grade
  applications.
                   Things to Consider
•   The many uses of GPS
•   Computer interface to be able to download data.
•   Uploading maps of areas you intend to visit.
•   A unit with an interface that you are comfortable with.
•   What is most important to you? Are the datums you require available?
    Which paper maps, if any, will you be using along with your unit?
    What type of interface? Do you need additional software and cables?
    Do you want internal maps? What uploading capabilities and amount
    of space is available? Battery life? Waterproof? Available accessories
    how accurate do your downloadable maps need to be? Need DGPS?
    WAAS?
             Keep in Mind

A navigation receiver is not a survey device
but it more accurate than most of the
digitized maps you use it with. Remember
many of these maps were digitized using
paper maps.
            The Comparisons

• Garmin Etrex Series
• Other Garmin units
• Thales Navigation units (formerly Magellan)
Manufacturer        Garmin           Garmin              Garmin
Model               Legend           Venture             Vista
Size (WxHxD)        4.4”x2.0”x1.2”   4.4”x2.0”x1.2”      4.4”x2.0”x1.2”
Weight              5.3 oz           5.3 oz              5.3 oz
Batteries/life      2AA / 18 hrs     2AA / 20 hrs        2AA / 12 hrs
Waypoints           500              500                 500
Routes              20 / 50 ea       20 / 50 ea          20 / 50 ea
Display Size        2.1” x 1.1”      2.1” x 1.1”         2.1” x 1.1”
Upload memory       8MB              1MB                 24 MB
O.Ext.antennae      N/A              N/A                 N/A
Basemap             Basemap          Worldwide city Db   Basemap
Map options         MapSource CD     Pts of Interest CD MapSource CD
WAAS enabled        Yes              Yes                 Yes
Compass/Altimeter   No / No          No / No             Yes / Yes
Accuracy            <15 m            <15 m               <15 m
                    <3mWAAS          <3mWAAS             <3mWAAS
List Price          $268             $194                $375
Manufacturer      Garmin           Garmin           Garmin
Model             Emap             GPS 12 Map       GPSMap 76
Size (WxHxD)      5.5”x2.4”x0.8”   5.8”x2.1”x1.2”   6.2”x2.7x1.2”
Weight            6.7 oz           9 oz             <16 oz
Batteries/life    2AA / 12 hrs     4AA / 36 hrs     2AA / 16 hrs
Waypoints         500              500              500
Routes            50 / 50 ea       20 / 30 ea       50
Display Size      2.2” x 1.7”      2.2” x 1.5”      1.6" x 2.2"
Upload memory     Only w/ card     1.44 MB          8 MB
O.Ext.antennae    Yes              Yes              Yes
Basemap           Basemap **       Basemap **       Detailed b.m***
Map options       MetroSource      MapSource CDs MapSource CDs
WAAS enabled      No               No               Yes
Compass/Altimeter No / No          No / No          No / No
Accuracy          <15 m            <15 m            <15 m
                                                    <3m WAAS
List Price        $242             $364             $400
Manufacturer      Thales Navigation   Thales Navigation   Thales Navigation
Model             Map 330             Meridian GPS        Meridian Platinum
Size (WxHxD)      6.2”x2.0”x1.3”      6.5”x2.9”x1.3”      6.5”x2.9”x1.3”
Weight            7 oz                8 oz                8 oz
Batteries/life    2AA / 10 hrs        2AA / 14 hours      2AA / 14 hours
Waypoints         500                 500                 500
Routes            20 / 30 ea          20                  20
Display Size      2.3”x1.4”           1.75”x2.2”          1.75”x2.2”
Upload memory     8MB                 Opt SD card         Opt SD card
O.Ext.antennae    Yes                 Yes                 Yes
Basemap           US Cities, Hwys     US Cities, airprt Also waterways
Map options       MapSend Streets MapSend CD              MapSend CD
WAAS enabled      Yes, upgradeable Yes                    Yes
Compass/Altimeter No / No             No / No             No / No
Accuracy          <15m                <15m                <15m
List Price        $270                $210                $350
 The Potential of
     WAAS
Wide Area Augmentation System




100 meters:                     Accuracy of the original GPS
                                system under Selective Availability
                                (SA) program.
15 meters:                      Typical GPS position accuracy
                                without SA.
3-5 meters:                     Typical differential GPS (DGPS)
                                position accuracy.
< 3 meters:                     Typical WAAS position accuracy.
Manufacturer        Garmin           Garmin            Thales Navigation
Model               Vista            GPSMap 76         Meridian GPS
Size (WxHxD)        4.4”x2.0”x1.2”   6.2”x2.7x1.2”     6.5”x2.9”x1.3”
Weight              5.3 oz           <16 oz            8 oz
Batteries/life      2AA / 12 hrs     2AA / 16 hrs      2AA / 14 hours
Waypoints           500              500               500
Routes              20 / 50 ea       50                20
Display Size        2.1” x 1.1”      1.6" x 2.2"       1.75”x2.2”
Upload memory       24 MB            8 MB              Opt card 8MB $34
O.Ext.antennae      N/A              Yes               Yes
Basemap             Basemap          Detailed b.m***   US Cities, airport
Map options         MapSource CD     MapSource CDs     MapSend CD
WAAS enabled        Yes              Yes               Yes
Compass/Altimeter   Yes / Yes        No / No           No / No
Accuracy            <15 m            <15 m             <15m
                    <3mWAAS          <3m WAAS          <3m WAAS
List Price          $375             $400              $210 ($244)
         Costs for Map Add-ons

Garmin Metroguide     $200.00

Garmin Waterways      $65.00

Garmin Road &          $100.00
Recreation
MapSend for Meridian – $80.00
Streets & Destinations
                           In closing
       For the types of uses we were searching for

• Basic functions for primarily recreational use
• Ability to contain some basic street information as well as uploading
  features
• The accuracy that is possible with WAAS technology




The Meridian GPS by Thales Navigation seems to
be the best choice.
               References

• Garmin www.garmin.com
• Thales Navigation www.magellangps.com
• Yahoo Shopping (for prices not listed on
  corporate sites) www.yahoo.com
• www.gpsinformation.net
• Trimble www.trimble.com
• “Receiver Survey” GPS World January 2001

				
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posted:11/23/2011
language:English
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