GPS On The Move

When it comes to precision farming, global positioning is the heart and soul of any strategy.

And as the GPS revolution rolls into its second decade since it truly became a widely available public access technology, much has changed for the better. Satellite signal availability and accuracy options have increased significantly. And over the course of the last seven years, the availability and accessibility of real-time kinematic (RTK) correction has moved rapidly from the new technology on the block to an investment that more and more end-users are able to afford.

We’re certainly closer to a vision that Mike Gomes, agriculture product manager for receiver manufacturer Topcon, discussed in a 2006 article in sister publication PrecisionAg Special Reports. “The idea is that global positioning becomes like a utility,” he said. “For instance, when you turn on a light, electricity makes it work; or when you turn on the water, it is clean and usable. Imagine there being no time of day issues, no issues with compatibility or satellites or your position on Earth. It’s just there, always on and ready to use.”

Inside agriculture, receiver technology has evolved to the point where it is built into most equipment, notes Paul Welbig, marketing manager at Raven Industries. “The reliability, cost, and usability of GPS technology has really reached a point where customers trust it and use it in more and more applications,” he says.

Evolution Of The Revolution

GPS has gone through an evolution almost simultaneously with, and arguably no less remarkable than, the Internet. Like the Internet, GPS was in its infancy back in 1995, and product developers were working on a receiver that provided accuracy good enough for agriculture applications. Initial products were only providing accuracy measured in meters, which didn’t fit the bill, says Sid Siefken, product manager for Trimble.

“The data farmers got from recording the yield monitor was jumping around 2 to 5 meters,” he explains. “So a farmer would get his data back and say, “I didn’t drive like that — this isn’t accurate enough for my application.”

A little more than a decade later, an end-user interested in georeferencing field operations using a GPS system has a wide range of options in receiver technology, from the very basic sub-meter system all the way down to the sub-inch accuracy level. These developments have come both in signal technology and at the receiver level.

There are essentially four sources of GPS signals available today. The Wide Area Augmentation System, built originally to replace the current system for coordinating commercial air traffic, is available at no cost from the federal government. The signal  provides accuracy averaging around 6 inches — a bit more or a bit less depending on the receiver used.

OmniSTAR provides a subscription-based signal with three options depending on accuracy needs — VBS at the basic level, followed by XP and HP, providing accuracy as good as 3 inches at the top end. The Coast Guard beacon system also continues to be accessible to users within range of a beacon.
Finally, there’s real-time kinematic systems, which require a static ground receiver and “rover” receiver that provides true sub-inch accuracy. The other potential benefit with RTK is repeatability — if the static receiver is returned to the precise same location each time it is used, or is permanently installed in one location, it will provide guidance that is repeatable. That is, you’ll be able to return to the same spot in the field, year over year.

The big news with RTK systems is price point reduction and accessibility. A few years ago, you could expect to invest $30,000 at the low end to add RTK. Individual systems today come in at under $20,000, and where there are tower networks available to pick up a broadcast signal (for a subscription fee), potentially much less than that.

“Cost-effective and easy-to-use base stations have put the power of repeatability through use of RTK within the reach of more (users),” says Deane Malott, director of product marketing for AutoFarm.

Satellite Signal Improvements

While RTK systems have gotten the lion’s share of the  press, satellite-based GPS — and the receivers that use the signal — also have been steadily improving over the years. One of the most significant improvements is the availability of a “dual-frequency” signal.

Dual-frequency receivers use two of the GPS frequencies, L1 and L2, explains John Pointon, marketing manager at OmniSTAR. “Up until a few years ago those were exclusively used by surveyors who wanted high accuracy, and because of cost the ag market used only single frequency L1. With L1, you really cannot get better than submeter accuracy.

“People who are serious about automatic steering and planting and strip-till need to be within an inch or two, and thus need a dual-frequency receiver,” he continues. “Dual frequency permits better compensation for atmospheric errors and helps with the complex calculations required for high accuracy positioning. This is really where the growth is in the market today.”

Of course, not everyone needs or wants that kind of accuracy. So manufacturers are offering a wide range of accuracy options that balance price and value expectations.

What should you consider when weighing up receiver options? Pay attention to the antenna design of the receiver. Antennas today are designed for specific purposes, and knowing their abilities and limitations will ensure you are getting what you expect. It’s also important to note that newer technology is better. A newer, higher quality antenna will deliver a cleaner signal that minimizes interference that is generated by reflected signals and obstacles in the path of a signal.

Leave a Reply

Latest News
CHS St. Paul, MN fertilizer terminal
CropLife 100Farmers Union Oil Co. Votes To Join CHS
September 30, 2016
Eligible voting members of Farmers Union Oil Co., a diversified agricultural retailer based out of Oslo, MN, have cast affirmative Read More
EmployeesOABA Program Develops Future Generation Of Agribusiness…
September 29, 2016
The Ohio AgriBusiness Association will select up to 25 promising leaders to participate in a leadership enhancement program early next Read More
ManagementThoughts on CropLife America and the PSM Appeal
September 29, 2016
Editors Paul Schrimpf and Eric Sfiligoj talk about the recent CropLife America annual meeting and the successful appeal of the Read More
Corn Field
Industry NewsMarrone Bio Innovations’ SVP And Chief Sustainability O…
September 29, 2016
Marrone Bio Innovations, Inc., a leading provider of effective and environmentally responsible pest management and plant health products, announced today Read More
Young Corn Field
StewardshipStudy: Ohio Farmers Doing ‘A Good Job Of Managing…
September 27, 2016
Leaders from Ohio’s largest grain farming organizations announced today that Ohio farmers are doing their part in effectively managing phosphorus Read More
Growmark FS Outlet
Industry NewsGROWMARK To Purchase Suncor’s Share Of UPI
September 26, 2016
GROWMARK and Suncor have reached an agreement in which GROWMARK will purchase Suncor’s 50% interest in UPI, Inc. in Ontario, Read More
Corn Field
Eric SfiligojFacing Ag Industry Challenges
September 26, 2016
At the 2016 annual Mid America CropLife Association (MACA) meeting in September, a pair of crop protection company representatives discussed Read More
Syngenta Seedcare Institute
Seed/BiotechSyngenta Opens New North America Seedcare Institute In …
September 23, 2016
Syngenta unveiled its new Seedcare Institute in Stanton, MN, during a recent grand opening celebration. More than 150 industry leaders, Read More
StewardshipMonsanto Invests $1.6 Million In System To Quantify Gre…
September 23, 2016
The USDA – Natural Resources Conservation Service (USDA-NRCS) recently awarded the National Corn Growers Association (NCGA) and its Soil Health Read More
Pipe rack
LegislationCourt Sides With Ag Retailers On PSM
September 23, 2016
The D.C. Court of Appeals has ruled the Occupational Safety and Health Administration violated the Occupational Safety and Health Act when Read More
ManagementPacific Coast Fertilizer Announces Interest In Longview…
September 22, 2016
Pacific Coast Fertilizer LP (PCF) announced at the Cowlitz Economic Development Council board of directors meeting its interest in developing Read More
Young corn plants in soil
UncategorizedCool Planet Raises Additional $9 Million To Commerciali…
September 22, 2016
Cool Planet has announced the first close of a new financing round to commercialize the company’s Cool Terra Engineered Biocarbon Read More
Crop InputsJim Loar Promoted To President And CEO Of Cool Planet
September 22, 2016
In a move that reflects and reinforces the company’s commitment to the agricultural market, the Cool Planet board of directors Read More
BlendersNorth Dakota Coop Debuts Dry Fertilizer Plant
September 22, 2016
North Central Grain Cooperative has begun operations at a new dry fertilizer plant at its Rolla, ND, site. It is Read More
Crop InputsMonsanto, Bayer Officials Defend Proposed $66 Billion M…
September 21, 2016
Top officials for Monsanto and Bayer defended their proposed $66 billion merger before skeptical senators on Tuesday, insisting that the Read More
ManagementUpcoming Shows & Recent Events
September 19, 2016
Editors Paul Schrimpf and Eric Sfiligoj talk about upcoming trade shows and events and review the Mid America CropLife Association Read More
Industry NewsVerdesian Life Sciences Appoints New CEO
September 19, 2016
Verdesian Life Sciences, a plant health and nutrition company, today announced that its board of directors has named Kenneth M. Avery Read More
Corn
Crop InputsEPA Settles With Syngenta For Alleged Multi-Regional Pe…
September 19, 2016
The U.S. EPA has announced a multi-region settlement with Syngenta Crop Protection, LLC (Syngenta) in Greensboro, NC, for alleged violations of Read More