water is that most important resource for life, both for humans and for the plants we consume. Globally, 70 percent of freshwater consumption is used for agriculture.
I study Computer and Information Technology at Purdue Polytechnic Institute and lead Purdue’s Environmental Networking Technology (ENT) Laboratory where we address sustainability and environmental challenges with interdisciplinary research on Agricultural Internet of Things or Ag-IoT.
The Internet of Things is a network of objects equipped with sensors so they can receive and send data over the Internet. Examples include wearable fitness equipment, smart home thermostats, and self-driving cars.
In agriculture, it includes technologies such as underground wireless communications, underground sensing, and in-ground antennas. These systems help farmers monitor real-time conditions on their land and apply water and other inputs, such as fertilizers, exactly when and where they are needed.
Soil condition monitoring, in particular, shows promise to help farmers use water more efficiently. Sensors can now be wirelessly integrated into irrigation systems to provide real-time information on soil moisture levels. Studies suggest this strategy can reduce irrigation water needs by 20 to 72 percent without impacting day-to-day operations in the fields.
What is the Agricultural Internet of Things?
Even in arid places like the Middle East and North Africa, agriculture is possible with efficient water management. But extreme weather events caused by climate change make this difficult. Repeated droughts in the western United States over the past 20 years, along with other disasters such as wildfires, have caused billions of dollars in crop losses.
Water professionals have been measuring soil moisture to make water management and irrigation decisions for decades. Automated technologies have largely replaced hand-held soil moisture meters due to the difficulty of performing manual soil moisture measurements in production fields in remote locations.
Over the past decade, wireless data collection technologies have begun to provide real-time access to soil moisture data, leading to better water management decisions. These technologies could also have many advanced IoT applications in public safety, urban infrastructure monitoring, and food safety.
The agricultural internet of things is a network of radios, antennas and sensors that collect real-time crop and soil information in the field. To facilitate data collection, these sensors and antennas are wirelessly connected to farming equipment. The Ag-IoT is a complete framework that can detect conditions on farmland, propose actions in response, and send commands to farm machinery.
Networking devices such as soil moisture and temperature sensors in the field makes it possible to control irrigation systems autonomously and save water. The system can schedule irrigation, monitor environmental conditions, and control agricultural machinery such as seeders and fertilizer applicators. Other uses include estimating soil nutrient levels and identifying pests.
The challenges of laying networks underground
Wireless data collection has the potential to help farmers use water much more efficiently, but putting these components into the ground comes with challenges. For example, at the Purdue ENT lab, we found that when the antennas that transmit sensor data are buried in the ground, their operating characteristics change drastically depending on how wet the ground is. My new book “Signals in the Ground” explains how this happens.
Farmers use heavy equipment in the fields, so antennas must be buried deep enough to avoid damage. If the floor gets wet, the moisture will affect communication between the sensor network and the control system. Water in the ground absorbs signal energy, which weakens the signals sent by the system. Denser ground also blocks signal transmission.
We have developed a theoretical model and antenna that reduces the influence of the ground on underground communications by changing the operating frequency and system bandwidth. With this antenna, sensors placed in top soil layers can provide real-time soil condition information to irrigation systems at distances of up to 200 meters (650 feet) — longer than two football fields.
Another solution I’ve developed to improve in-ground wireless communications is to use directional antennas to focus the signal energy in the desired direction. Antennas that direct energy into the air can also be used for long-distance wireless underground communications.
What’s next for the Ag-IoT
Cybersecurity is becoming increasingly important for the Ag-IoT as it matures. Networks in farms need advanced security systems to protect the information they transmit. There is also a need for solutions that enable researchers and agricultural advisors to bring together information from multiple farms. Aggregating data in this way will lead to more accurate decisions on issues such as water use, while preserving producer privacy.
These networks must also adapt to changing local conditions such as temperature, precipitation and wind. Seasonal changes and crop growth cycles can temporarily alter the operating conditions for Ag-IoT devices. By using cloud computing and machine learning, scientists can help the Ag-IoT respond to changes in the environment around it.
Finally, the lack of high-speed Internet access is still a problem in many rural communities. For example, many researchers have integrated wireless subsurface sensors with Ag-IoT into center-pivot irrigation systems, but farmers without high-speed internet access cannot install this type of technology.
Integrating satellite network connectivity with the Ag-IoT can help disconnected farms where broadband connectivity is not yet available. Researchers are also developing vehicle-mounted and mobile Ag-IoT platforms that use drones. Systems like these can provide continuous connectivity in the field, making digital technologies accessible to more farmers in more places.
This article was originally published on The conversation by Abdul Salam at Purdue University. Read the original article here.
