WHEN CLAY Mitchell and his father Wade made the leap to assisted steering technology in 2000, they upped the ante by asking that the real-time kinematic (RTK) signal correction system they installed do double duty.

In addition to providing RTK signal correction, they wanted the same radio system to be the backbone of a two-way wireless system to beam the Internet to farm equipment in the field. They also wanted the system to be able to monitor field equipment from afar, as well as remotely control their grain-handling system.

After a fair amount of trial and error with two different RTK-capable radio systems, today the Mitchells can send and receive e-mails, stay abreast of the markets and monitor and control their grain-handling system from the tractor, sprayer or combine cab.

“We knew that some of the radios used for RTK could be configured for communicating back and forth, but typically they aren't used this way,” Clay Mitchell says. “We took the [radio] components we had and are getting more use out of them. There are a lot of nuances to make it work. It can be a bit challenging.”

Setting up the system, and its multiple capabilities, was a tall order. The 2,400-acre operation is spread over a six-mile by 10-mile area in rolling country near Buckingham in southeastern Iowa. The Mitchells use a combination of 17 radios, including a base station, a fixed repeater and three mobile repeaters in three trucks to beam the RTK signal to areas of the farm that are more challenging to reach because of the topography.

The number of radios the Mitchells employ is dictated by RTK needs. Not all the radios are needed for the Internet portion of the system to be effective.

“The more radios we have, the more robust the RTK,” Mitchell says. “The reliability of the RTK system gets better and better.”

System backbone

The backbone of the Mitchells' radio network is based on the Safari Mobile Network system from NavCom Technology (www.navcomtech.com), a subsidiary of John Deere. Designed primarily for private wireless communications networks for business and industry, it also has the capability of relaying RTK correction signals. The system has multiple radio channels that provide both the relatively slow data rate typically used for RTK signals and higher speeds suitable for high-speed Internet — in this case, 512 kilobits per second (kbps). The system operates in the 2.4-GHz spectrum also used by fixed wireless Internet service providers, home wireless computer networks and Wi-Fi “hot spots.”

The Mitchells have a base station radio on a tower located toward one end of the farm and a repeater on a grain leg toward the other end, about five miles away. In combination with mobile repeaters, the system provides seamless roaming between nodes, much like radio systems used for cellular telephone networks.

The RTK portion of the system delivers correction signals to both John Deere and Trimble assisted steering systems in the Mitchells' combine, two tractors and self-propelled sprayer, and implement steering systems on the planter and fertilizer applicator.

The Mitchells access the Internet in various implements with laptop computers, as well as with a PC-based sprayer monitor, manufactured by KEE Technologies, in their sprayer.

Connection payoffs

The Mitchells harness their private wireless network to stay abreast of the markets and the weather and to conduct farm-related business via e-mail. The network also allows them to monitor and control their grain-handling system via the Internet from the field and to monitor the status of spraying operations.

“Pulling information into the tractor cab helps us farm more efficiently,” Mitchell says. “People have had the image with autosteer that you might be in the tractor watching movies. This is not the direction this is going.”

Assisted steering, and the wireless network, allow the Mitchells to bring capabilities typically tied to the farm office into the field. “Being able to watch the weather radar during planting makes a huge difference,” Mitchell says. Because the farm is relatively spread out, monitoring the progress of scattered rain showers allows him to continue planting by alerting him to fields that aren't receiving rain.

Efficiencies gained this way, as well as extended workdays and other assisted steering benefits, allow the Mitchells to rely on a single 12-row planter for their 2,400 acres.

The network also speeds machinery repairs and improves their weed-control program. “If I have a breakdown, I can order a part online or see if the dealer has it,” Mitchell says. “I can look at herbicide labels to answer questions that come up when I am spraying. And it often is easier to get support via e-mail instead of the telephone.”

The Mitchells have focused special attention on using the wireless network to enhance their ability to monitor spraying, harvest and grain-handling operations.

Numerous sensors added to their self-propelled sprayer allow Wade, for example, to remotely monitor Clay's location with the sprayer and how full the tank is. This allows him to time trips with the nurse tank. Other sensors show field speed, the real-time application rate, the boom height, whether a spray nozzle is clogged and other functions. These data can be monitored by anyone on their network, including the sprayer operator, and are automatically recorded on a computer.

During harvest, the network boosts efficiency by allowing the combine operator and others with access to their network to monitor and control their grain drying and storage setup from afar. The Web-based system continuously captures dryer temperatures, grain moisture content, and grain bin temperatures and moisture levels. Augers also can be switched remotely through the network.

The major network-based addition to the combine is a Web camera, which is pointed from behind the operator to the head, and can be monitored via the network. “The Web cam is nice for safety reasons,” Mitchell says.

Costs vs. benefits

The Mitchells estimate that the cost of their dual-duty wireless network was about $100,000. RTK-related expenses were a big chunk of that.

Individual Safari Mobile Network system base station, repeater and remote radios used in the Mitchell network sell for $2,500 to $5,000 each, according to Jalal Alisobhani, director of communication products for NavCom Technology.

“The Mitchells are getting a lot of additional capability for only a little more money above the cost of a dedicated RTK radio system,” he says. “Our vision is that this real-time connectivity is something that will be coming to farms.”

But he acknowledges that the market is in its infancy. The Safari Network is a key enabling technology, “but because it is just one piece and not a complete end-to-end solution, it takes the kind of forward thinking that the Mitchells and other early adopters have brought to the table to pave the way for acceptance of real-time farming and Internet access in the broader farming market,” Alisobhani says.

For their part, the Mitchells say their double-duty radio system is well worth the investment. Since 2000, what were formerly three farms operated by family members is now run as a single entity. Because of RTK-corrected assisted steering, the Mitchells use a single 12-row planter and tractor, instead of three of each as in the past or a 16-row or 24-row planter common for operations their size. There have been other equipment efficiencies as well.

The Mitchells have instituted controlled-traffic no-till and strip-till systems that have allowed them to cut out primary tillage, reduce other costs and increase yields. The controlled traffic system, which allows them to concentrate wheel traffic on less than 20% of their ground, wouldn't be possible without RTK-corrected assisted steering.

“We do better financially with RTK-corrected autosteering and the radio system than we would without these systems,” Mitchell says. “Yields are higher and machinery costs are lower. It allows better utilization of machines.

“This system is expensive, but it is still cheap relative to the savings,” he adds. “A new tractor costs $250,000. The electronics behind our system is just a little over $100,000.”