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I am trying to figure out a way to get GPS data from a remote source to a Raspberry Pi. The remote source would be a helmet mounted GPS receiver so it would need to be small and preferably inexpensive. A $30 USB GPS dongle would be perfect. The question is how to get the data to the Raspberry Pi board. Line of sight will not always be an option so RF would be best I'm thinking.

I just don't know what to look for. Can someone point me in the direction of some kind of small transmitter/receiver I can use to get the data from the GPS device to the Raspberry Pi? Or if there is some GPS module that has a transmitter built in that would be great too. The typical range of transmission will be between 10 and 500 feet so I suspect that Bluetooth will be out though I don't really know much about the max range of Bluetooth. I really just don't know where to start looking so even some keywords or search terms that could point me in the right direction would be helpful.

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xbee is super simple, it is like a wireless serial port, just buy two of them, configure them to the baud rate of your gps receiver (sparkfun has MANY gps receivers (the GP-635T is very small, look at the picture of it on top of a quarter) on the host side get an ftdi breakout or something like that to get it converted to usb for the computer. The xbee modules simply find each other and whatever is on the rx of one goes out on the tx of the other. I have used the longer range models and gone well over 500 feet (require an antenna and of course the antenna choice has a lot to do with it). Look at specs for the less expensive modules with on board antennas.

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  • \$\begingroup\$ Thanks for your help. I'll research xbee to see what I can find. \$\endgroup\$ – William Feb 5 '13 at 19:34
  • \$\begingroup\$ expensive compared to zach's answer but quite simple to use (if you get the right modules do your research first) \$\endgroup\$ – old_timer Feb 5 '13 at 19:51
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I know spark fun has some simple ASK transmitter and reciever pairs that run right from uart. https://www.sparkfun.com/products/8946

I've used them in a few projects up to 60 feet reliably. You can compute a simple checksum to check for errors such as XOR. a more robust but expensive solution is xbee transmitter For your log range requirement, your gps is probably 1hz or a 10 hz update speed, you basically just transmit the Nmea string with a checksum and then parse it on the receiver side

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  • \$\begingroup\$ The link you posted is a retired product but that gives me an idea of what to look for thank you. And it's definitely within the size requirement I want. \$\endgroup\$ – William Feb 5 '13 at 19:34
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    \$\begingroup\$ The NMEA strings already have checksum, so there's no need to calculate one on the transmitter side. It's the number after the final * in the string. \$\endgroup\$ – AndrejaKo Feb 5 '13 at 19:55
  • \$\begingroup\$ @William A good book if you get into Xbee or equivalent, is amazon.com/Building-Wireless-Sensor-Networks-Processing/dp/… \$\endgroup\$ – zacharoni16 Feb 5 '13 at 21:38
  • \$\begingroup\$ @zacharoni16 I got this book. I'm sure it will help greatly when I get the funding to work on this. I'm estimating this will cost around $200 to set up based on what I see so it could take me a little bit to pull the funding together but the book made me confident that I can do what I want to. Thank you. \$\endgroup\$ – William Feb 7 '13 at 19:49

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