I have a project where I want a Bluetooth/BLE contact over several hundred meters. I have some boards from Nordic Semiconductors, which mention a range up to 600 meters. But for various reasons I'd like to replace one item with an Arduino, particularly the Nano BLE. I'm an experienced Arduino user, but have no experience in Bluetooth. The Nano would receive commands from the host board. A single command would be just one byte (plus whatever the protocol needs). A lower priority would be the Nano sending commands back to the host board.
At what maximum range can I expect the Nano to work?
Please see BLE very weak signal - Nano 33 BLE - Arduino Forum reply #8.
Could you please provide the source for the 600m claim? I would like to have a look.
The issue is separating marketing from the technical data. If you would take a BLE product like a heart rate monitor and a sports watch and you would get a range of 600 meters the product would be crap. Because it would waste energy and transmit your data over unnecessary long distance e.g. compromise your privacy. That's why most BLE products will not support these ranges.
Johan_Ha:
The Nano would receive commands from the host board. A single command would be just one byte (plus whatever the protocol needs). A lower priority would be the Nano sending commands back to the host board.
That is not how BLE works. BLE is not FM radio. For BLE the peripheral and the central device need to communicate in both directions even if the application layer does not.
Johan_Ha:
But for various reasons I'd like to replace one item with an Arduino, particularly the Nano BLE.
Sorry, distance for communication depends on both sides. You need to look at the link budget. e.g. transmit power (limited by government regulations), antenna efficiency, loss in the medium (attenuation) and receiver sensitivity.
Your data rate is low. This would allow you to make use of BLE Long range which trades data rate with distance by using forward error correction. It adds redundancy to increase the chance of receiving a valid packet. But you need all devices to support this mode which was not included in the first BLE spec and is optional in the current BLE specification. It needs to be supported in the hardware.
Because antenna with directional characteristics can increase distance another factor is movement. If you have static devices you could increase distance by having directional antenna. If your devices are moving you need antenna with non-directional characteristics.
Ok, I don't know yet everything about Bluetooth. I get a picture there's Bluetooth. And there's BLE, which would be Bluetooth Low Energy, right? And there's Bluetooth Long Range. I don't know if those are the right words, and I don't know how separate from each other the concepts are. But we are talking about Long Range here. Sorry, if I missed to use those two words here and sorry if BLE is not used together with Long Range. Anyway, this page mentions the 600 m range:
Johan_Ha:
I get a picture there's Bluetooth. And there's BLE, which would be Bluetooth Low Energy, right?
Yes, and Yes. Bluetooth and Bluetooth Low Energy are two incompatible protocols.
Johan_Ha:
And there's Bluetooth Long Range. I don't know if those are the right words, and
Long Range is an optional feature in BLE. It is is enabled by a coded PHY. That is the physical layer on the BLE implementation and therefore requires a chip hardware that supports it.
Johan_Ha:
I don't know how separate from each other the concepts are. But we are talking about Long Range here.
Long range basically has the same BLE stack above the PHY but the PHY creates the same bit multiple times (500kbps = 2x, 125kbpts = 8x) when it sends a packet. This gives the PHY on the receiver side a higher chance of reading the bit correctly.
Johan_Ha:
Anyway, this page mentions the 600 m range:
Thanks. I had a read through the page and recommend you read it as well. Here are the points I got out of it.
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the test did not care about power, the transmit power was 0dBm (1mW) which would be OK but the radio was active all the time. In BLE the nodes communicate only in a connection interval. The longer the interval the better the power saving.
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the effective data rate was not 125kbps but much lower. They were happy when they received a packet or so per second. So, losing 99 of 100 packets was OK for their test.
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they did the test at a beach in Norway, How many young woman with smartphones disturbing the test do you think where at that beach? If it was more than one, they would have called the cops to arrest the creepy nerds.
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the boards have directional antenna characteristics, and they used the antenna direction which would give them the best result.
So, for your application the range will be different. More closely to my results which were done without Long Range. With Long Range (125kbps) it looks like you could get twice the distance.
And as mentioned before with some directional antennae design you could get some additional boost at the cost of needing fixed positions.
Thanks for pointing out that. That's good to know. What I'm trying to do is a wrist device, which can keep contact with my dog running free in the field. The Nano 33 BLE would be in the dog collar. I never actually thought of a 600 m range. More like 50 m.
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