When it comes to technology discussions, there's a phrase that irrigators may want to pay attention to: the “internet of things” (IoT). In an industry that wants to get a better grip on water usage, the rising use of new kinds of sensors could make a significant difference.

The concept is to use low-power sensors in higher numbers that transmit information to a powerful gateway to the web, so that the information is available through the cloud for you to use. Today, most soil sensors are elaborate systems that require careful setup and location work in part due to their cost.

However, the rise of low-cost sensors could make a difference. A company out of the Netherlands — Sensoterra — has a $100 sensor that can be part of an in-field network communicating to that internet gateway. The low-cost sensor may not be as precise as the $3,000 competitor, but at $100 each — lower with volume pricing — you can put more sensors in a field. The net result is a better profile of water use in the field than a single sensor can provide.

The Sensoterra sensor is just one kind being deployed using this low-power, in-field system. Many companies have systems under development that relay crop sensor information to that gateway. Senet is a provider of cloud-based software and service platforms for IoT work.

The company recently announced it had launched a global low power, wide area virtual network that could redefine IoT connectivity.

Senet has long used LoRaWAN tech as a way for sensors to communicate on a network. The company’s new network is the Senet Low Power Wide Area Virtual Network — LVN for short — which aims to create a standard for IoT communication that builds on the LoRaWAN network. The Senet LVN provides an Iot architecture built for secure cloud-based services. It can be a host platform for radio access network participants. It provides roaming between participating operators and other connectivity providers using the standard.

Without getting too technical, this approach could bring added support for IoT use in agriculture with a network providing new functionality.

In announcing the new system, Bruce Chatterley, Senet’s CEO, says that there is an IoT land grab taking place among network operators: "The Senet LVN addresses these challenges by modernizing IoT connectivity and offering ways for an entire ecosystem of participants to monetize their networks and services." For farmers, it could mean a more reliable way to network on-farm sensors. You can learn more at senetco.com.

Thinking of a mesh
One challenge of the IoT sensor in the field is an operative world — low power. These are usually sensors that capture information and use low-power broadcast to reach a higher-power gateway that can do what's called "internet backhaul" to get the information to the cloud. But network coverage is limited by the farthest reach of the sensor from the gateway. Get too far and there would be gaps in the coverage.

Consider the current approach — each sensor is sending its data directly to the gateway like a hub and spoke system. So your "wheel" is limited by how far your sensor can transmit to that central hub.

A different approach would be the creation of a "mesh" network where each sensor could talk to the other and pass information along that network to the gateway.

You're no longer limited to the hub and spoke system; instead, the "field of sensors" could be shaped as needed. An L-shaped field wouldn't be left out of connectivity, but rather sensors around the field would share their information to the gateway. The idea is relatively simple in principle, but can be complicated to implement.

Cambridge Consultants, a Massachusetts firm that concentrates on a wide range of new ideas, such as the idea of mesh network for field sensors. "We've looked at using LoRaWAN in a mesh protocol," says Niall Mottram, head of agri-tech at Cambridge Consultants. "Each sensor becomes a transmitter and receiver, and no matter the topography of your farm, the network can get around objects and terrain."

He added that in the middle of Illinois where the ground is flat, a standard hub and spoke network approach would work fine, but in hilly country this could make a big difference for farmers capturing sensor data around obstacles.

Mottram explained that with the low-power wide area network, which has no cellular fees or data transmission costs, farmers could have sensor input around the farm. Adding the mesh network approach guarantees the data can move to your cloud through only one cellular-enabled gateway, which is a long-term cost savings.