Multiple connectivity options exist for agtech today. Four major considerations for each connectivity option include:
- Range: How far away can end devices (the devices doing the sensing) be located from edge devices (the devices sending data to the cloud or network)? Is line of sight required?
- Bandwidth: How much data needs to be sent over the connection?
- Power: How much power does the solution require? Are batteries enough, or is solar power an option to power the devices?
- Cost: System price matters, especially when you’re scaling up a solution over a large operation.
So, which wireless communications option is best for you and your customers’ operations? What follows is a comparison of the most widely-recognized options on the four major factors of range, bandwidth, power, and cost. If you’re short on time, skip to the comparison table at the end for a brief overview of each connectivity option.
WiFi
WiFi works across a few buildings, but expanding the range of your signal to fields and other areas of your operation costs more than it’s worth. A WiFi signal is attenuated (read: reduced) by walls, large devices, and bodies of water. That’s not ideal for an agricultural operation with large pieces of equipment, bodies of water, and miles of fields. And even without a lot of things in the way, WiFi range really isn’t that great. A general rule of thumb in home networking says that WiFi routers operating on the traditional 2.4 GHz band reach up to 150 feet (46 m) indoors and 300 feet (92 m) outdoors. Newer WiFi devices operating in the 5 Ghz range experience even more attenuation than traditional ones.
The major benefit of WiFi is that you can send a large amount of data over the connection. After all, this is the same type of connectivity you’d use to stream Netflix or play video games. So, while you can send huge amounts of data, the range is too short to be valuable in a large agricultural operation, especially in large fields.
WiFi hardware is also relatively power-hungry compared to other connectivity options designed for embedded devices. Connecting devices with WiFi also assumes that there is an uplink to the rest of the internet at the wireless access point your devices are connecting to.
Result: Short range, high bandwidth, draws a medium amount of power. Relatively inexpensive connectivity if you already have an internet connection.
Cellular
Cellular devices share many of the benefits of WiFi, and can be more flexible. Depending on the network your cellular device connects to, they can have very high bandwidth.
Bandwidth for cell connections:
- 3G: 2 Mbps
- 4G: 200 Mbps
- 5G: 1+ Gbps
However, if each device has its own cellular connection, it will require its own subscription, and those subscriptions costs can add up. A cellular connection is also limited if your service provider doesn’t have a cell tower in range of the device you want to connect. This can be a big factor for farms or other rural locations, where cell service may be fine at the house, but could be non-existent a few miles down the road.
A cellular connection can connect to the cloud wherever there’s cellular coverage. However, the high bandwidth and easy cloud connectivity comes at a cost: power. Cellular connections require a lot of energy. If devices are battery-powered, they need a way to charge their batteries. If the device has access to line power, that’s not a problem. But for agricultural applications, remote is the norm, in which case a renewable source like solar power is a good option.
Result: Range dependent on cell signal, high bandwidth, draws a substantial amount of power, and is relatively costly on a per unit basis.
Satellite
Satellite uplink can be used in areas with no cellular coverage. Range is essentially a nonfactor, because satellite coverage is available nearly everywhere on the planet. A disadvantage of this type of connectivity is that it requires line-of-sight with one or more satellites, so it won’t work indoors or in areas with a cluttered or non-open sky (under trees or near large buildings).
Satellite hardware and data subscriptions both cost more than cellular, and satellite has significantly reduced bandwidth. Power consumption is typically substantial, requiring additional supplemental power. However, satellite options are getting more affordable as smaller, smarter satellites are taking to the sky.
Result: Maximum range, low bandwidth, draws a lot of power, and requires a clear sky to maintain connection. The most expensive option, today.
LoRa and LoRaWAN
LoRa is a Long Range radio technology that uses inexpensive, low-power radios to transmit small amounts of information over long distances. LoRa uses an unlicensed part of the radio spectrum — just like you can plug in a WiFi router without having to get a broadcast license first. The relatively low frequencies (in the 900 MHz range in the US, and either 433 or 868 MHz elsewhere around the world) means that the radio signals have an easier time traveling long distances and passing through obstacles like walls or vegetation. LoRa signals can even get through substantial foliage like dense irrigated corn.
In contrast to other 900 MHz radios, LoRa radios use a clever (and patented) method of modulating the signal to allow the receivers to pick up even the faintest signal without getting confused by noise and interference. In exchange for far-reaching range, the relatively low frequencies that LoRa uses limit the speed at which large amounts of data can be sent. This means LoRa has a modest bandwidth of 27 Kbps. For applications where you don’t need constant data transfer, sending a few small data packets per hour is more than sufficient.
LoRaWAN, however, describes a standardized way of linking LoRa devices into a Wide Area Network. You can think of LoRa as the technology required to create a better envelope and letter, while LoRaWAN is the set of rules that your mail carrier follows to get your letters from one place to another in an organized and secure way. Just like you can use an envelope without using the Postal Service, you can use LoRa radios without organizing them according to LoRaWAN.
A LoRaWAN network consists of many end devices which use LoRa radio to communicate with a nearby gateway. Multiple gateways then communicate with a central server which is connected to whatever other parts of the internet are required. That means a LoRaWAN network requires cellular subscriptions only for the LoRa-to-cellular Data Gateways to get data to the cloud. By using cheaper LoRa connections where you can, instead of using cloud-connected technology for each device, you’ll save quite a bundle on monthly subscriptions. In addition to cost-effectiveness, LoRa devices have very small power requirements. Battery-powered devices can last months or years in the field with no battery replacements.
Result: Long range, low bandwidth, ultra-low power. Priced to scale over multiple devices.
Connectivity Platform from RealmFive
We believe in creating a Connectivity Platform that’s built for agriculture — which means optimizing products for remote applications. We’ve created a network to connect devices that couldn’t be connected before, because either there wasn’t a good signal, not enough power, or it was prohibitively expensive.
- Range: With modified LoRa technology called R5 Core, you get below-canopy connectivity through dense foliage. This exceptional range makes it possible to connect your entire operation to the cloud with minimal subscription costs.
- Bandwidth: RealmFive devices have a small data footprint. This lower bandwidth requirement makes it possible for lower power use and longer range.
- Power: This drop-in network doesn’t require line power: solar power or standard batteries — like AA or D cell — will keep your devices running through the season.
- Cost: The Connectivity Platform is priced to scale. Up to 50 sensing devices can connect over LoRa to a single Gateway Communications Device, which cuts down on per-unit data subscription costs.
Here’s a table that summarizes all of the information from above. (CLICK TO ENLARGE)
Contact RealmFive today to find out how our Connectivity Platform can give your operation simple, reliable, and scalable connectivity.
This content is brought to you by RealmFive.
RealmFive is changing the way customers interact with agricultural technology in areas including agronomy, inventory, irrigation, livestock, and machinery. Using highly improved long-range radio technology and easy-to-deploy devices RealmFive’s Connectivity Platform enables remote monitoring, control, and data-driven decision-making. The RealmFive Connection Platform is modular and flexible, allowing for simple third-party integration into the platform and a robust API to other digital farming platforms. With an expanding portfolio of applications including soil moisture, weather, irrigation monitoring, and state monitoring, RealmFive is bringing sensor-to-cloud solutions to agriculture.
