Posted on

Why Use VHF/UHF GPS Transponders Instead of Cellular Connected Devices

Often a system decision comes down to cellular vs. VHF/UHF RF communications.

Cellular based GPS transponders and cell phones rely on a public cellular radio networks to connect to the carrier’s network, which then passes the GPS location information to the end user via the Internet.

VHF/UHF radio networks utilize private licensed radio frequencies to communicate.  The radio networks are privately operated, and may be owned and controlled by the system operator.

When trying to decide if dedicated VHF/UHF GPS transponders like the Raveon ATLAS PT or M7-GX transponder is the right choice, or cellular transponder is the right choice, keep these very important points in mind:

  1. You will know where everyone is at all times.  A GPS Transponder operates at all times, with fast update rates, even when cell service is not available. They even operate when a base station is off-line.
  2. Battery Life.  A GPS transponder can run for days on a single charge.  Most cell-phones will operate 8 hours or so when tracking in real-time.
  3. Emergency Assistance.  In an emergency situation, both technologies can be used to summon help.  But if the person is incapable of moving or unconscious, making a call is not possible.  The VHF/UHF GPS transponder will not only continue to send the locations out, but alert that no motion is taking place.
  4. Search and Recovery.  Raveon’s GPS transponders automatically, continuously, and quickly transmit GPS location and status.  Rescue personnel can use a tablet or laptop computer to locate the transponder in real-time, live while searching.  Finding the transponder can take only minutes. No internet connection is needed.
  5. No Voice Communications.   In many situations it is undesirable to have the people being tracked to be able to talk amongst themselves. This could be for training purposes, privacy, or security. Learn more about how the RavTrack system is designed by viewing our asset tracking infographic.
  6. Fast Updates.   Cellular locators get quite expensive unless they are configured for very slow update rates.  Tracking hundreds of vehicles or people requires an advanced channel-access protocol like Raveon’s TDMA protocol. Airtime is free on the VHF and UHF bands.
  7. Log Files.  With fast updates, the system can store GPS data to log files for later review or in case there is an incident, the log can be queried to determine what happened during the incident.
  8. Keep People Honest.  Often GPS tracking is done to monitor behavior to verify that they are following rules and staying within limits and boundaries.  Cell phones will not help in these situations. They can be turned off (The ATLAS PT’s power button can be disabled).
  9. Rugged.  The ATLAS PT is submersible to 1 meter of water, very rugged, and made from aluminum.  Few cellphones can take the abuse the ATLAS PT can.  When people lives are at stake, a rugged, long-life product is important.

Comparison of Features

Feature

GPS Transponder PRO

GPS Transponder CON

Cellular GPS
PRO

Cellular GPS
CON

Voice Communications

User’s Can’t communicate. Security. Privacy.

Cannot call for help without pressing the ALert Button

Users can chatter amongst themselves.

Users can cheat if they are supposed to be on their own.
Voice comms takes up bandwidth used for GPS tracking.

Battery Life

Excellent
24-48 hours

8-12 hours

Real-time Tracking

Excellent

   Limited bandwidth  Excellent

Expensive

Safety System

Great situational awareness

No voice. Cannot talk to rescue.

User must operate their own private radio network.

Can talk to rescuers

Will not work when out of cell coverage or cellular system is down.

User Cannot Turn Power Off

Always On when needed

Requires charger to shut off.

None.

Users can turn radio off if they don’t want to be tracked.

No Motion Alert

Automatic Transmission if idle to long.

Sometime false alerts when sleeping/resting.

None

Few cellular transponders have this feature.

Live Tracking by Searcher and Rescue

Rescuers, cadre or commanders can drive right up to the transponder.

None

Personnel can use voice to help direct searchers to find them

Sometimes difficult to explain location.  Must be within cell service, and probably standing up.

Learn more about the advantages of the RavTrack system by attending our webinar. We work with some of the most successful companies and government agencies, including the FAA. Find out more about our customers.

Posted on

Campus Bus Tracking (Missouri State University)

Guest Blog posted by Corbin Campbell, Electronics Support Services Missouri State University
Just a little history, our Assistant Director of Public Safety had a project for me. Missouri State University had the ability to GPS track the shuttle bus fleet for the students, faculty, staff, and public safety. This was done using a wireless carrier and through a smartphone on each shuttle. The problem was the speed and the recurring data cost. We wanted to be able to track our shuttle fleet without the cellular cost and in real time. Other GPS systems that we looked at had cellular data fees and would only update once a minute. The cost of these systems were also not in the public safety budget. He knew there had to be some other options.  Being the campus radio guy, he thought that I might have seen something that would do what he wanted.  After some looking and talking with other GPS tracking  vendors, I came to the website of Raveon and the RV-M7-GX GPS modem. I knew that I had something that would do what I wanted but I wanted to to find out more.

bus tracking using gps radioI called Raveon and I started out with the tech support people since these are the guys that have to fix the problems.  After talking with them, I knew that I had to demo this product to see if the hype matched the product.  Sales at Raveon reviewed the project with me to make sure we had a good fit, and arranged to send us the proper gear for testing. A demo was programmed up on a UHF frequency that I had and the units were set up for 1 second updates. We used RavTrack PC for the interface and Google Earth for the mapping. After 30 minutes in the demo, we were sold. At that point Raveon sales located a contract our purchasing department could use and expedited a full system to meet our funding deadline.

In our full system installation, we are tracking 15 shuttles and our base unit is on the 20th floor of one of our buildings. We are tracking our shuttles every three seconds so we can add more shuttles without having to do a mass reprogramming. The shuttles use the combination GPS-UHF antennas to broadcast the data to the base station. The shuttle data is filtered, received, and converted to TCP\IP.  Networking tweaked the network to get the data to our Web Development team.  Web Development have taken the GPS data and created this custom map where students, faculty, and staff can pull up the shuttle locations, shuttle routes, speed, and direction. Just click on Shuttle Map and the route and you will see the bus stops and the icons that represent the shuttles. Web Development is also working on apps for the iPhone and Android to make it simple for students, faculty and staff.

I won’t say how much the system cost, but the system will pay for itself in less than two years from the savings in cellular data fees alone.

If you want to do GPS tracking this is the way to go.  If you don’t believe me, demo the product because the hardest thing that you will have to do is send it back!!!

P.S. Since we installed the system I have received multiple calls from my peers at other organizations.  They don’t believe we can track our fleet with 3 second updates, even though we see it live, and tell me I must be mistaken.  When I add that we do all of this without monthly service fees I think they write me off as a teller of tall tales.

Corbin Campbell
Electronics Support Services
campus bus tracking Missouri state