The “cellular NTRIP to low power radio repeater” receives RTK correction data through cellular connectivity and then transmits the same data with a radio modem. Just like a radio repeater but cellular connection replaces the first radio link of a radio repeater approach. The device is an NTRIP client for the caster at the base and then transmits the correction data just like a radio would do at the base (but at lower power which should mean no need for a radio licence at all).
Every repeater approach has some drawbacks too. A mixed approach means the rover should have a radio and should be able to use cellular connectivity too, perhaps via the driver’s personal phone.
PS. I’m still confused about the complete scenario. Earlier on you mentioned fields are only 2 km from a static base. Is this a planned base site for your own base? 2 km should be nothing for a low power unlicensed radio unless there are big obstacles in-between the base and the rover (mountain). If there is, a low power to low power unlicensed radio repeater might work well.
Also lost with the long range towers, how come 45 km away if the fields are 2 km away? Or are these free RTK2GO sites. A hand written map would clear things up.
These are government owned towers for there radio network.
Exactly right, if the government bases is a no-go, my homebuilt static base (with 4G coverage) would be within 2km of the furthest fields, but these fields do not have cellular coverage nor line of sight from base.
What is an example of such a device, and can one not build repeater for the cellular network itself, to get it into the dead spots, if a booster is not good enough?
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Thanks for all those clarifications.
Now I’d like to understand how severe is the obstruction blocking line of sight view? I’ve run a 1W base radio at the 400 MHz range with the antenna inside my (wooden) garage at less than 7 metre height and reached easily 5 km range with no line of sight view. Some foliage, small forests in the way, no high mountains.
Considering the NTRIP to radio repeater, there are several commercial products but I’d build one from a GPRS modem and a commercial radio.
I did some tests with LoRa radios, and it looks very promising, I still have to test more
https://discourse.agopengps.com/t/questions-about-lora-radio-915mhz-and-gps/8132
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This is a map of 4G Internet coverage on farm, the spots that are not purple coloured are dead spots and they are a bit broader than that.
This is above sea level. At 124m will be my base.
The pinkish lines are the low spots and then there are hills between them and base.
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Thanks for the reply, have you done any auto steering yet?
These lora radio’s are cheap enough to give try regardless
Another possibility for you is this: https://www.ardusimple.com/rtk-ssr-corrections-from-space/
Seems like this is not an option in the southern hemisphere?
some good news since NTRIP is already available.
