Questions about LoRa radio 915mhz and GPS

Hi! my father owns a small farm in western Paraná Brazil, I’m trying to implement Agopengps for operations like spraying and seeding (soybean and corn) and I have a few questions:

1- Is Ublox ZED F9P better than NavSpark PX1122R? or do two deliver similar results?

2- is it possible to send RTCM corrections using these LoRa radios connected directly to the UART of the ZED-F9P or PX1122R?

sorry for my bad english


In my opinion you should choose PX1122R.
The F9P is also good, but it seems the PX1122R is good enough for your application.

Yes you can buy it.
Buy at least 2 (or 3) unit.
After receive it, you will also need to reconfigure the TX power , “speed in the air” and the UART baudrate to match the bandwidth/distance requirements.
You also need to purchase a “UART-to-USB” module to be able to connect to a computer to configure .

thank you so much!!

researching about LoRa modules I had another question, some Lora modules say to pack the data in a number of bits while others do continuous sending, which one should I choose since the RTCM messages are bigger than the packet sent by LoRa?

for example

LoRa E32-868T30S


Just make sure RTCM messages have a bandwidth less than airspeed - 30%.
For example if RTCM with 1005(1) ,1008(1) ,1077(1) ,1087(1) ,1127(1) ,1032(1) with about 800 Bytes/s .
Then the air speed needs to be guaranteed at > 1100 Bytes/s. (about 8800 bps).

Hello Bruno, I’m also new here in the community, and I also live in West Paraná. I’m excited about AgOpenGPS.

Result of the first test.

I finally managed to test my system, I configured the RTK base station to send messages 1005(2), 1074(1), 1084(1), 1094(1), 1230(1), the station is operating at 1Hz

Using LoRa module E220 900T 30D This was the range obtained, until losing the RTK fix, Detail, the station was mounted on a tripod and there was a house and a garage in the line of sight, in addition to the relief shown in the image.

I was very impressed!

Resultado do primeiro teste.

Finalmente consegui testar meu sistema, configurei a estaçao base RTK para enviar as mensagens 1005(2), 1074 (1), 1084(1), 1094(1), 1230(1), a estaçao está operando em 1Hz

Usando modulo LoRa E220 900T 30D Foi esse o alcance obtido, até perder o RTK fix, Detalhe, a estaçao estava montada em um tripé e havia uma casa e uma garagem na linha de visão, alem do relevo mostrado na imagem.

Fiquei muito impressionado!

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Set your LoRa antenna height up to 10 -15m will get more than 3km.

So just tacking on to this thread under the same topic, I have these rylr896 (and manual here)hoping to be able to transmit my correction stream from my base station but I guess I don’t actually know how to have it stream. I have them configured via AT commands correctly I think?

I have my 2 simplertk2b communicating via jumper wire, then they stop when I try to swap to the lora tx/rx’s. I am not super familliar so I’m definitely missing something here. Thanks for any suggestions!

you must make sure that the radios can communicate, check the channel, address… You can connect the radios by usb to a computer and use the realterm software to verify that the data is being sent correctly. The baudrate configured in the radios must be the same configured in the Ardusimple boards

So I can get them to communicate by sending an AT command and see the received response. Will the simplertk2b bs able to transmit with it like this/ can they do AT commands?

Everything is at the correct baud rate.

ok, i’m not fluent in english so the translation may be causing some misunderstanding.

you are comfortable with the radios via AT command right?

you can send data from one radio to another through the UART port? or only AT commands for each radio separately when connected to the PC?

AT commands are PC->Radio communication, you need to make sure the radios communicate with each other.

Bom dia. Ficou bom teu projeto. Tenho duas placas F9P, que uso como PPP mas queria por um rádio para transforma-las em RTK. Estou procurando esse rádio. Essa configuração é muito difícil? Tu fizestes mais testes? Quais distâncias tens alcançado?

Boa noite! infelizmente ainda não consegui avançar com o projeto, esse foi o único teste que realizei, mas os rádios são muito simples de configurar. Assim que tiver alguma atualização posto aqui.