The right technology for your farm is dependent on the environment, the available network coverage and the things you want to measure. Every farm is different but generally speaking in the Southern and Eastern states LoRaWAN and NB-IoT are the better value options, but in more remote areas satellite is the best option.
The quadrant chart below is a guide to help you think about the options. Each technology has different characteristics but they all do the same thing, ie get the data from the sensor to your phone or computer. In the final result the data will be identical no matter how it got there, which means the best option is often a mix of technology. For example a farm might put up a LoRaWAn gateway that covers 80% of the farm, and fill in the black spots with some NB-IoT devices.
Farmo is sometimes asked to explain the different technology options to groups of farmers. These are some of our notes [here].
LoRaWAN is a communication technology designed for low power, low data devices. It allows up to 100 sensors devices to connect to a single gateway up to 15km away by line of sight. Buildings, trees, and deep gullies will reduce the transmission distance achieved and it may be only 3-4 kms in some areas. The main benefit of LoraWAN is the lower running costs per device.
An essential part of the LoRaWAn system is the gateway, which receives data from all the sensors, and then sends this data to the cloud.
The LoRaWAN security protocol dictates that all data is encrypted on the device, and will be passed blindly through the gateway to your organisation's endpoint, where they are decoded. This means that gateways can pass messages, but they cannot read them.
The cost saving principle around LoRaWAN is that devices communicate with the gateway over a local network and only the gateway itself requires a simcard to pass on messages to the cloud. Even better if there is wi-fi available where you install the gateway, the gateway can use that wi-fi to send its data to the cloud.
LoRaWAN messages transmit very small amounts of data and are not designed for sending movies or CCTV. However a lot of information can be extracted from a small amount of data. For example, a gate open can be recorded as "0" and a gate closed as "1", and since we know the location of the device and the time the message is sent, we can start to get a rich picture of what's happening at that gate over time, all from a "0" or a "1".
Sending small amounts of data more extends the battery life of the device. LoRaWAN devices can be expected to last years in the field before the battery requires changing. Battery life is relative to the power used for each transmission. If your gateway is far the device must use more power per transmission and the battery will not last as long.
Also note that battery life is directly related to how often data is sent. So if all other things are equal, the battery on a tank sensor transmitting levels twice a day will last 12 times as long as the same device transmitting every hour.
TNN mapper is a site that displays LoRaWAN coverage:
Gateways can be set as "private" or "public" and allow any conforming LoRaWAN device to connect. This means neighbours can share gateways and increase their individual coverage areas.
Note that different countries have different LoRaWAN standards and you must match the device type with the gateway type for it to connect. In Australia we use both AU915 and AS923 standards, so make sure to check this.
NB-IoT (Narrowband IoT) is a communications technology designed for low power, low data devices to connect to the internet via the same carriers that connect your mobile phone.
The coverage for NB-IoT is up to 30km more from the tower than the 4G network, so if your mobile phone works on the site, you can assume NB-IoT devices will work. Additionally due to the lower siganl bandwith, the penetration through buildings and cement tanks is better than 4G and LoRaWAN.
Every Farmo NB-IoT enabled device comes with its NB-IoT sim card included.
NB-IoT is not as cheap as LoraWAN (which doesn't require a sim in every device), but then NB-IoT doesn't require thecapital expense of a LoRaWAN gateway.
Whatever technology you choose, the data your device sends and the data that you receive is the same. It doesn't matter how it gets there, just that it gets there. So choose the one that can do the job required at the lowest cost.
Click on the map below for Telstra NB-IoT coverage. The published coverage map is based on "modelling" and is a rough guide only. You will likely know where you can get signal on your farm in much better detail from your own experience.