|
|
| GeoCommunity Mailing List |
| |
| Mailing List Archives |
| Subject: | [gislist] How about tracking a group of Hikers in real-time? |
| Date: |
07/05/2005 12:30:02 PM |
| From: |
Mark Martens |
|
|
Bill:
Sounds like you know a lot about this space. I am interested in finding out what it would take to build a system to track a group of hikers over a wide area, say like a 24-hour eco-challenge. I have the software that wil place them in a virtual location, I just need the GPS transmitter receiver and of things.
Do you think you could point me towards some useful information sources?
Mark
gislist-request@lists.geocomm.com wrote:
Send gislist mailing list submissions to
gislist@lists.geocomm.com
To subscribe or unsubscribe via the World Wide Web, visit
http://lists.geocomm.com/mailman/listinfo/gislist
or, via email, send a message with subject or body 'help' to
gislist-request@lists.geocomm.com
You can reach the person managing the list at
gislist-owner@lists.geocomm.com
When replying, please edit your Subject line so it is more specific
than "Re: Contents of gislist digest..."
Today's Topics:
1. realtime vehicle tracking (Simmonds, Ashley (DTEI))
2. Re: realtime vehicle tracking (Bill Diaz)
3. Calculating a string as a number? (Matt Bachman)
4. Re: Calculating a string as a number? (Zach Travis)
----------------------------------------------------------------------
Message: 1
Date: Tue, 5 Jul 2005 18:27:50 +0930
From: "Simmonds, Ashley (DTEI)"
Subject: [gislist] realtime vehicle tracking
To: gislist@lists.thinkburst.com
Message-ID:
<9D1D8F15E14032438253BB94449EE25703686A08@sagemsg0005.sagemsmrd01.sa.gov.au>
Content-Type: text/plain
sure this has been discussed before. could someone point some fingers at
where some step-by-steps in this arena might be located...
i've been researching APRS a bit, and am already good with GIS and stuff,
but i need to get a good handle on how to transmit a GPS signal from a fleet
of cars, and recieve that signal into my application.
danke
ash simmonds
------------------------------
Message: 2
Date: Tue, 5 Jul 2005 07:55:50 -0500
From: "Bill Diaz"
Subject: Re: [gislist] realtime vehicle tracking
To: "'Simmonds, Ashley (DTEI)'" ,
Message-ID: <030301c58160$dec9ae50$6301a8c0@Dell3G>
Content-Type: text/plain: charset="us-ascii"
Ash,
See below:
>-----Original Message-----
>From: gislist-bounces@lists.geocomm.com
>[mailto:gislist-bounces@lists.geocomm.com] On Behalf Of
>Simmonds, Ashley (DTEI)
>Sent: Tuesday, July 05, 2005 03:58
>To: gislist@lists.thinkburst.com
>Subject: [gislist] realtime vehicle tracking
>
>sure this has been discussed before. could someone point some
>fingers at
>where some step-by-steps in this arena might be located...
>
>i've been researching APRS a bit, and am already good with GIS
>and stuff,
>but i need to get a good handle on how to transmit a GPS
>signal from a fleet
>of cars, and recieve that signal into my application.
Step by step information for commercial AVL system design is hard to come
by, since many companies use proprietary systems and methods. Methods of
transmitting and receiving a signal from a fleet can vary considerably. An
APRS like system may not be suitable for commerical application for a
variety of reasons.
APRS (Amateur Position Reporting System) is used by Radio Amateurs
World-Wide to report postions of various mobile and fixed assets. However,
it has some serious drawbacks. Position reports do not require or expect an
ack. There is no way of knowing if the position information reached the
desired destination. Often, a position report collides with a postion
report from another station, and both position reports are lost since there
is no retry mechanism for position reports.
Commercial AVL systems generally have robust protocols to ensure information
is delivered to the intended destination or is stored locally for later
transmission or download.
The key to a successful AVL systems is a dependable communications system
which covers the intended market area. If the market area is small, a single
base station may suffice and costs can be somewhat reasonable. If the
market area is larger than can be covered by a single base station, costs
can quickly escalate. Many AVL systems in the US utilize existing cellular
networks to carry information since the captial costs are mimimal compared
to a dedicated system. Most networks claim 95% coverage in the US.
Microburst and Cellemetry offer data services which utilitze the control
channel of cellular systems to allow subscribers to relay limited amounts of
data. Other commercial services are available as well.
Several AVL systems do not use radio at all. They simply log position
information into an onboard computer for later download to an AVL system.
Some are hybrid systems. They store location information until they come in
range of the AVL radio system and then send the stored information.
Asset position information can be sent or stor
|
|
Sponsored by:
For information
regarding
advertising rates
Click Here!
|
