I have done 40km LOS on simple 1/4 wave wire antennas for RX and TX, 434Mhz, BW62500, SF8, 3mW. standard hardware, basic software. Expect half that range at 868Mhz.
Wow. This is really perfect!!!
I have tested several devices and all are the same in my case. Then, as you mentioned, it might be ‘not driving the switch correctly in software’. In a very simple case, I use two simple TX/RX examples (SX_01a_TX_LoRa and SX_01a_RX_LoRa) and SX1272 library. I have tested several alternatives. My pure setting for 868 MHz is here:
sx1272.ON();
e = sx1272.setMode(4);
e = sx1272.setHeaderON();
e = sx1272.setChannel(CH_10_868);
e = sx1272.setCRC_ON();
e = sx1272.setPower(‘M’);
e = sx1272.setNodeAddress(3);
I use the following command to transmit a packet (message) to the node no. 8:
e = sx1272.sendPacketTimeout(8,message,50);
and this for receiving the packet in a for loop:
for (unsigned int i = 0; i < sx1272.packet_received.length; i++)
{
my_packet[i] = sx1272.packet_received.data[i];
Serial.println( my_packet[i]);
}
I wonder if it would be possible for you to kindly provide me a link to the library (.h and .cpp file) you have used and the setting for the SX1276 that you have successfully used?
If it is hard to write it here, my email is mehrdad_babazadeh@yahoo.com
Thanks a lot again,
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Your problems seem to have no relevance to antenna length or problems with the things network.
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Thanks anyway. It is still a problem and I have to look for any solution or somebody who can help.
Best wishes.
Hurts Eyes 
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Correction:
I had forgotten the 869.525 MHz frequency used for the RX2 downlink:
868 MHz band LoRaWAN frequencies range from 867.100 MHz to 869.525 MHz with middle frequency 868.3125 MHz. The optimal LoRaWAN antenna length would thus be (velocity factor not included):
299,792,458 / 868,312,500 = 0.3452587 m for full wave length (1λ) antenna
0,1726294 m for half wave length (½λ) antenna
0,0863147 m for quarter wave length (¼λ) antenna
In practice this still makes too little difference (with using 868.0 MHz for the calculation) to be significant.
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Did you check your software and library what settings it is actually sending to the sx1272? You might be setting the bandwidth wrong, you might be setting the output power wrong, you might be selecting the power boost the wrong way, you might be inadvertently activating the current limiting, you might be setting the ramp-up wrong, etc, etc. I’ve had my share of ‘pulling out my hair’ moments with -in my case- the RFM95, but in the end, it all makes sense and you just have to get acquainted to the documentation.
Best thing to do, hook up a logic analyzer to the communication between processor and sx1272, select proper decoder and check what configuration commands are actually sent to the module. This is much easier than it sounds.
hello sir we trying to build a lora network for our project with lora nodes from Microchip - RN2483 , 868mHz frequency. we are using the following antenna dimensions , tried with both 50 mm and 108 mm , the range maximum we could attain in just few meter, with line of sight. could you guide us how can we attain max distance
The lengths normaly used for antennas are 1/4 the wavelength or 8.6cm for 868Mhz, although in practice maybe up to 1cm shorter.
So why your using 5cm or 10.8cm I cannot understand.
When you say a ‘few meter’ what does that actually mean ?
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thank you for respond sir,actually our antenna height is 10.796cm(big) and small antenna height is 5.1cm. when we testing with those antenna for lora nodes communication we are getting up to 20meters only but we need up to 500meters then what to do.
- what type of gateway do you use
- what node do you use
- what node software do you use
Whilst the antenna lengths do not seem to be optimum, they would still provide way more than 20m range, even at the highest of the LoRa data rates.
Those are the ranges you could expect with ‘line of sight’ when there are no antennas connected at all, so are you using a LoRa device that expects you to independantly setup the antenna switching between transmit and receive ?
Edit: On checking I see you are using the RN2483, are you connecting the antenna to the correct port on the RN2483 ?
1.what type of gateway do you use: right now we are not using any gateway,through node to node communication we are trying.we done in communication between two nodes but we are trying for long distance.
2.what node do you use: RN2483(microchip).
3.what node software do you use: we are using tera terminal for peer to peer communication
we are using antenna in correct port.please send me a document or link for long distance communication(node to node)
I think you missunderstand … I cannot think of a way of missconfiguring even a raw LoRa module, RFM9x or DRF128xF so that it performs so badly. I have played with LoRa devices at a low level, node to node, a great deal in the last 3 years, and every time I have seen very short range (20m or less) it has been due to no antennas or faulty modules.
The RN2483 does much of the low level LoRa configuration for you, so I cannot see how it is possible to configure it for extreme short range.
The Things Network does use the RN2483 for nodes, but not in node to node configuration or via Tera Terminal, so this is not the best place to ask questions for your particular application.
thank you so much
Can you post a picture of the RN2483 modules used, plus details of how the antennas are connected? I’m sort of suspecting bad connections.
So what Adafruit recommends below is wrong? Would it be advisable to go for 8.6 cm length antenna instead of 8.2 cm?
No they are right. You have to apply the velocity factor of arround .95.
86mm multiplied with 0.95 gives 82mm.
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