GPS coordinates updated every second (Sailboat tracking)

Good day everyone,

I am pretty new to Lora(wan) and I was wondering if I could use Lora(wan) to track a fleet of sailboats in a regatta. Most tracking software companies are very expensive, some use GPRS, some use 868 MHz (Lora) to receive GPS data from each participating boat.

  • Is it possible to modify a tracking system to update it’s posistion every second?
  • Is it allowed to send that amount of data (battery life is not my concern, it should last 6-8 hours)
  • How many receiver / gateways would I need to track approx 60 boats?
  • Should I create my own Lora network or could I use LoraWan (I own concentrators from Dragino)
  • Which GPS tracking devices would you recommend?

I would like to develop a much cheaper way to track boats in a race, the races usually take place max 3-4 km out of shore. In most cases, there is no issue setting up antenna’s and Lora receivers locally (so LoraWan would not be absolutely needed)

Thanks for your help.

Hi @IT-Gypsy, that’s a lot of questions! My thoughts relate to the EU_863_870 spectrum and regulations.

Tracking system update per second. Not using LoRaWAN due to 1% duty cycle. Might be possible using LoRa with Listen Before Talk (LBT).

Allowed to send that much data: Not with LoRaWAN in EU due to 1% duty cycle. Might be possible using LoRa with Listen Before Talk (LBT) on multiple channels.

How many receiver/gateway: Assuming LoRa you should think about 8 (?) receivers, each one on a different radio frequency. Spread the vessel senders across the frequencies.

Own LoRa or LoRaWAN: I think that this would have to be a complete own-build using LoRa. Build your own vessel GPS and TX devices. Build your own LoRa RX devices. Build your own back-end software.

Which GPS tracker: I am not aware of any commercial LoRaWAN GPS tracker that will do anything close to this. I think that you would have to build your own trackers to go on the vessels.

Those are careful answers to your direct questions. There are other matters:

  • In my opinion you should not attempt this using EU LoRaWAN or LoRa on the EU LoRaWAN frequencies.
  • Most GPS receivers that I am aware of that use NMEA standards only output a location every second so you could find yourself repeating or skipping per-second positions.
  • You would be much better to use mobile/cellular network services for this use case. These are pretty much always available to at least 10 km offshore. Use a rugged cellular/WiFi hotspot on the vessels.
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Hi,

Thanks for the in dept reply.
NMEA data can very easy be processed to Serial data,
The reason I try to avoid using cellular are the costs.
You would need a GPRS data (pre-paid) for each device.
Wi-Fi is hardly an option due to the amount of Access Points on the regatta venues.

I hoped using 868 MHz I might avoid returning costs.
Making sailboat tracking (for regatta’s) less expensive and more accessible.

When not using 868, but other frequencies, I might be in violation of local laws and although the transmission power is low, it will be a matter of time before you will be penalized.

I have contacted a (Chinese) supplier of Lora based tracking devices that replied that they can modify the firmware of their Lora(wan) tracking devices to send location data every second (after motion is detected)
But only on 433 and not 868.

Thanks again for the quick reply

Every second !

Thats not going to happen with TTN, even at the highest speed of transmission, which implies the yatchs are close by the Gateway, then you would be out of your fair use allowance in 9 minutes.

What you are attempting would be very difficult to keep legal with older point to point LoRa devices due to duty cycle restrictions.

However, it varies around the World maybe, but in some parts you can transmit at 100% duty cycle if you keep the bandwidth below 25khz. That used not to be very practical with the SX127x LoRa devices, but the newer SX126x devices work quite happily at very low bandwidths.

You would probably need to build a lot of seperate LoRa receivers.

Whilst I have provided the information above, this is not a forum for the discussion of poin to point LoRa.

These pure LoRa (not LoRaWAN) networks of ground stations provide flight objects tracking in EU on 868.2 MHz wtih 2-3 seconds position update interval (to comply with EU Tx duty cycle rule on this band and SF7 air time for aprox. 25-30 byte sized packets):

  1. Burnair
  2. AirWhere

The largest non-commercial community based network of ground stations GliderNet is curently using FSK modulation @ 1 second interval for tracking of GA aircrafts with FLARM, OGNTP radio protocols.
However, they have recently announced that they are going to add LoRa (a.k.a. “FANET protocol”) into the list of supported (de)modulations soon. They actually do already some experimental LoRa reception in Switzerland segment of the GliderNet.
Their ground stations are mostly Raspberry Pis with USB SDR dongle attached. LoRa reception is expected to appear in official 0.2.7 release of “OGN receiver” SD Card image.

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Have you ever looked at the LoRa specifications and how it works? Reading your posts I guess not. As @LoRaTracker mentioned, this is not going to work . If you want to know how many packets (airtime) you are allowed to send, check https://www.loratools.nl/#/airtime