I’ve heard rumours of some people using the 868MHz band for LoRa in New Zealand. When I interpret the regulations it seems like this is allowed, as long as you keep to these limits:
864-868MHz - maximum of 36dBm.
868-870MHz - only for “determination, telemetry or telecommand”, maximum of 3dBm, maximum of 1% duty cycle.
869.2-869.25MHz - Too small for a LoRa channel.
The range of 864-868MHz can work for a few LoRa channels. Between 868 and 869 where the default three LoRaWAN channels are located, the allowed power is much too low. For LoRa we normally use 14dBm. Using the 915MHz band is therefore a better fit because the regulations are slightly more relaxed.
New Zealand uses the AS923 LoRaWAN 1.0.2 Regional Plan definition, as ratified by the LoRa Alliance Technical Committee review and standards process. This band has two mandatory join channels (923.2MHz & 923.4MHz), and after a successful NW Join, the Network Server (NS) provides the device discrete 125kHz-wide channels in the next downlink via the CFList MAC and also Tx-power and other properties via the CFParameter MAC command. AS923 actual channels used (8 or 16) is operator specific (e.g. chosen and assigned to the device by the operator), and you can ask what these are, but as a developer, you don’t actually specifically need to know them due to the dynamic nature of AS923 join mechanisms, and they may change for a given operator over time as well.
Also, for the main New Zealand LoRaWAN nationwide operator, Spark NZ, the AS923 channel plan is an asymmetric one, with device uplink channels starting at 922.0MHz, and GW downlink channels starting at 925MHz and ending at 926.4MHz. AS923 FW compatible devices have been tested on this plan, and are used by customers today.
Good to get some feedback from NZ on this topic. It is best to follow the LoRaWAN definition, so we should consider following that for TTN.
On the other hand I see that Australia is also considering to change away from the official AU frequency plan. And then I heard Brazil adopted the AU frequency plan and dropped the US frequency plan.
For roaming purposes using as few as possible frequency plans will be best, but on the other hand you also want to make the most efficient use of the available spectrum. This last point was the main reason for originally suggesting that NZ follow the AU frequency plan. Especially due to the short physical and cultural distance between the two.
Hi, Spark NZ uses the two mandatory AS923 Join channels - 923.2MHz and 923.4MHz. The Spark NZ LoRaWAN NW (Actility ThingPark Wireless based) then allocates the further ongoing 125kHz-wide channels to the device to use, via the LoRaWAN 1.0.2 & AS923 spec’s “JoinAccept CFList” channel array.
@ttntecho In principle yes. The AU923 band is a subset of AU915-928 and this is in turn a subset of US902-928. Anything that does 915MHz should do it all.
@toogooda Yes you are allowed 1W EIRP (Equivalent Isotropically Radiated Power). This means that you have to take into account any gain in the antenna. Thus if you have a 10dBi antenna then you would only be allowed a transmitter of 100mW.
Also in the license there are conditions under ‘Special Conditions 23’ that state how much power you are allowed to transmit outside the allocated frequency band.
Currently setting up a bunch of gateways in New Zealand, but it seems we only get a successful connection when connecting our gateways to the UK handler. It’s a little odd, when we are connected to the Australian router, data doesn’t seem to get forwarded correctly to the EU handler.
Data forwarding between regions is a known issue. TTN advice is to use the same region for gateway and applications. Make sure the gateway points to the same address in its configuration and is not only set to the same region in the console.
That’d be ideal, but unfortunately the Australian router option doesn’t include any of the common integrations. We would point our gateway to the EU handler but it seems to timeout. I’ll keep experimenting and find the ideal settings.
The comment about the lower part of AU915 having power restrictions (in .nz) was news to me. I guess if EIRP is 1W for the rest of the band I’m pretty safe though, although maybe more significant for gateway operators.