Can I run gateway on 865 to 867 Mhz

Gateways
1

Hello All IOTian’s,

I have been interested in setting up and a small IOT community here in India. In the past I have used ESP8266, but due to limited coverage it didn’t turn out to be a successful project.

Recently I came to know about LoRa/LoRaWAN and started researching on it. It is exactly what I and all the IOT world looking for. Planned to order all the hardware necessary to build gateway/concentrator and nodes. But faced a new hurdle. In India 865 MHz to 867 MHz is open and not the 868 MHz on which all the transceivers are based. Now from what I have read from the data sheet of SX1276, I can program the chips to run on 867 MHz. Is it right? Can RN2483 be programmed for 867 MHz?

My next problem, I will be using iC880A-SPI – LoRaWAN Concentrator 868MHz or mCard with Raspberry Pi for the gateway. If some how I manage to set my nodes to transmit on 867 MHz, will iC880A/mCard be able to receive it. Perhaps it too can be programmed to listen to 867 MHz?

I want to make sure I order right stuff, because as of yet we don’t get these things in India and import duty is heavy.

I will appreciate if this community will help me build IOT for India.
“Shukriya” (Indian way to say Thank you)

1 Like
2

Hello Swap20,

Glad to hear you like the look of LoRaWAN for your projects. Yes the SX1276 can cover the lower frequency in India, but no the RN2483 doesn’t have support for that - because its a certified module and the LoRaWAN spec doesn’t yet include 865-867 MHz. Its only a matter of time, but in the interim you would have to re-engineer both the end nodes and gateways to operate at those frequencies.

Are there any other radio systems in India using 868.1, 868.3 & 868.5 MHz (the 3 default channels for 868 LoRaWAN)??

3

Hi JDP,

Thanks a ton for confirming, I am Relieved to know workaround exists to use band between 865 and 867 with Sx1276.

To be honest I have no clue why Indian gov did not include 868MHz as free to use. But good news is they are planning to open it as well, no idea when though.

I understand RPi based gateway with mCard/iC880A can handle multichannel. Am I right?

4

Actually in India we can also use 433 MHz, but with many restrictions such as max power is limited to 10 mW, channel bandwidth within 10 KHz and just using built in antenna. I guess this is not enough to reach a range o at least couple of Kms. On the other hand band between 865 - 867 MHz can use upto 1 watt.

5

Just a quick question, according to this link to make simple helical antenna for 868 Mhz

  1. Turns = 9, Coil Diam = 5.5mm, Wire Diam = 0.8mm, Coil length = 13mm

  2. The groundplane stub between last turn and solder stub = 4.5 mm

Is there any calculator to find the number of turns for 867 MHz? Or it does not matter that much.

6

We are running our commercial LoRaWAN network in New Zealand using the 865 to 867 MHz KotahiNet. We’ve learnt many things and are happy to share with people looking to operate in a non-standard frequency band.

On the gateway side, it’s been straightforward as it is only a matter of configuration. On the end node side, only LoRa modems or modules that are not locked to default EU 868 frequencies can be used. Our best experience has been with Microchip, IMST and SODAQ.

I’m interested to help you build community networks, especially in India, so happy to answer any questions about our experience with the 865-867 MHz band.

2 Likes
7

Hi Vikram,

Thanks for helping us out. My node will be on RFM95W - 868 MHz from HopeRF and I have confirmed from HopeRF that it can be adjusted to lower frequencies. Have you ever used RFM95W? can Microchip’s RN2483 be adjusted as well?

With gateway I am planning IMST with RPi. It will take time to arrive, till then for testing I will build a single channel gateway using RFM95W.

8

We don’t have experience with HopeRF yet but understand it can be configured. Reports about the actual performance have been mixed and so would advise checking out stability and coverage in your conditions.

On the other hand, we’ve got lots of experience with the Microchip RN2483. Details on how to configure it to work with our specific 865-867 MHz band are at http://kotahi.net/configure-microchip-rn2483-module/. Note that you can only do an ABP and not OTAA join if you are using non-standard frequencies.

I understand IMST has already got a custom implementation of the 865-867 MHz band so that’s easy. Our experience was good on the node side of things http://kotahi.net/imst/

9

Greatly appreciate for the guides, it made me understand a lot. If I understand right, mac set devaddr, mac set nwkskey and mac set appskey is something which I will have to assign in my gateway?

10

Your network server will have some way of enrolling nodes or end devices using Device EUI. For ABP join, it will generate the device address and keys (Network Session and Application Session). These then have to be entered into the node or end device. The “mac set …” are commands issue to the RN2483 node to enter the device address and keys.

11

So, @swap20, the gateway just forwards whatever it receives from nodes to a network server. To make the node known in The Things Network’s servers, one would use ttnctl devices register personalized to generate the ABP keys for a specific application and node; see its Quick Start Guide.

Too bad you apparently cannot use OTAA on non-standard frequencies: beware of frame counter security that especially affects ABP. You will need to store the frame counters in your device (or use the --relax-fcnt flag, which is actually insecure and only intended for debugging).

12

Hi All,

Thanks for the pointer. Today I finally got my hand on RFM95W. Hurrray!!!

My first step is to build single channel gateway using Raspberry pi 3 and RFM95W using this guide.

Enabled SPI via raspi-config.

I have connected wires as follow

RFM VCC - RPi VCC (pin 17)

RFM GND - RPi GND (pin 25)

RFM MISO - RPi GPIO 9 (pin 21)

RFM MOSi - RPi GPIO 10 (pin 19)

RFM SCK - RPi GPIO 11 (pin 23)

RFM NSS - RPi GPIO 8 (pin 24)

Also un-commented CFLAGS=-DRADIO_RFM92_95 from radio.makefile

[pi@raspberrypi:~/lora_gateway $ make lora_gateway_pi2
g++ -DRADIO_RFM92_95 -DRASPBERRY -DRASPBERRY2 -DIS_RCV_GATEWAY -c lora_gateway.cpp -o lora_gateway_pi2.o
g++ -c arduPi_pi2.cpp -o arduPi_pi2.o
g++ -DRASPBERRY2 -c SX1272.cpp -o SX1272_pi2.o
g++ -lrt -lpthread lora_gateway_pi2.o arduPi_pi2.o SX1272_pi2.o -o lora_gateway_pi2
rm -f lora_gateway
ln -s lora_gateway_pi2 ./lora_gateway

Then sudo ./lora_gateway_pi2

SX1276 detected, starting.
SX1276 LF/HF calibration
…
^$**********Power ON: state 0
^$Default sync word: 0x12
^$LoRa mode 4
^$Setting mode: state 0
^$Channel CH_10_868: state 0
^$Set LoRa Power to x
^$Power: state 0
^$Get Preamble Length: state 0
^$Preamble Length: 8
^$LoRa addr 1: state 0
^$SX1272/76 configured as LR-BS. Waiting RF input for transparent RF-serial bridge
Failed to get byte count on serial.

Please guide me, what did I do wrong?

Thanks to the efforts of C. Pham the above gateway now works on Rpi3

1 Like
13

Hi All,

I took this route and got a gateway up and running. Will test some more before linking up to TTN.

Thanks everyone

14

Thanks all wonderful people at TTN forum. I have since successfully deployed a single channel gateway and a node Running at 866.1 MHz. I connect ADXL345 an Accelerometer to Ardunio pro mini and modified this code to send data to TTN API.

And this is just the beginning!!!

15

@swap20 : I am from India & caught in same dillemma of using 866mhz. I have few hoperf 868 rfm95w chips which I want to configure to 866mhz. Can you share how you changed it to work on 866mhz. Also what is the range you are getting with your setup (rpi+rfm95w).
My mail id is manish@jetwave.in
Thanks.

16

Hi manish,

Greeting!

Did you configure the HopeRF chips to 866MHz.
If you have any info, Please share. I too faced the similar problem

Thanks!

Best Regards,
Velmurugan S

17

hii swap20
i also want to create lora network using RN2483 is it possible in india(in pune ) .
because In India 865 MHz to 867 MHz is open and not the 868 MHz so plz tell me about that
and we can use esp8266 module to create getway for that if it is not possible so plz suggest mi any other module for create getway .

18

Hello All IOTian’s,

i also want to create lora network using RN2483 is it possible in india(in pune ) .
because In India 865 MHz to 867 MHz is open and not the 868 MHz so plz tell me about that
and we can use esp8266 module to create getway for that if it is not possible so plz suggest mi any other module for create getway…
plz reply mi

19

Hello Swapnil,
Just wanted to ask whether you are successfull in your project?
what i want to know is 868mhz available for free licence in Indiaor not?

22

India has lisence free band for LoraWAN - 865-867 MHz