# Making a GPS Tracker

I've been looking for a fun project to do and wanted to make a GPS tracker like this:

https://www.cooking-hacks.com/documentation/tutorials/geolocation-tracker-gprs-gps-geoposition-sim908-arduino-raspberry-pi/#shield

The goal would be to set up an arduino controlled device that I can ping for location and then display this on my computer. However, it seems like I need a SIM card for that.

If I wanted to make a tracker but avoid paying some monthly fee to have a SIM card, how would I do that? Is there some SIM card that is pre-paid and allows for a certain number of messages each month?

Is there a way to send small messages over satellite communication? A GPS tracker would not be of much use if it is dependent on cell towers.

• You could ping iridium satellites, but that will be far more expensive than text messaging. – alex.forencich Nov 6 '16 at 3:02
• It depends on your country's operators if there is pre-paid SIM cards. In my county, T-Mobile offers both pre-paid and postpaid(monthly fee) SIM cards. You can transfer money to your pre-paid card, at least 10 $. You must transfer money at least once a year though or they will deactivate the card, so actually it is a 10$ / year fee in the cheapest scenario. Ask about at your operator. – Bence Kaulics Nov 6 '16 at 8:32
• There are some MVNOs who sell SIM cards for use in this kind of gadget for "IOT" purposes, but you'll have to look for them in your country. – pjc50 Dec 6 '16 at 11:39

This is somewhat dependent on what country you are in as use of the radio spectrum may be different from one jurisdiction to the next.

A system that exists today and tracks thousands of moving objects is called APRS (Automatic Packet Reporting System). It requires a radio amateur ("ham") license but that is pretty easy to get these days. It allows you to transmit the GPS coordinates (and cerain other information) to an infrastructure that already exists in many parts of the technically-developed world. You can go to http://aprs.fi/ and see all of the items being tracked on a Google Map.

There is also a proposed scheme which may be in some initial state of deployment called CSR Mesh. It uses BlueTooth-like communication into a mesh of network stations which carry the information all over the place.

But if you don't want to wait for CSR Mesh and don't want to get a ham license, you are rather limited to using the cell phone wireless network. In the USA, you can get a SIM card from Ting which costs $6/month plus whatever services you use, and you are billed for only what you actually use. For example 100 SMS messages in a month is$3 or 100MB of data is \$3.

There are a variety of products avaialable that make it easy to build or buy GPS tracker solutions. For example the usual places like AdaFruit and SparkFun, and BigRedBee for APRS gadgets (and several more).

I am assuming you want to attach your GPS tracker to something and view the information remotely. Unfortunately, I don't think there is any way to send messages without using cell towers. If you don't want to do that, I think your best bet is to save the data on your tracker using an SD card, and view the data offline.

• Yes, I want to be able to view the information remotely. – jonnyd42 Nov 6 '16 at 0:52