Towers, Towers Everywhere

RTK is getting more commonplace these days, should you consider it?

Published on: December 18, 2009

As automatic guidance systems gain in popularity, a lot of readers may find they want more precision and repeatability. In that case, most will tell you that RTK - for real-time kinematic - is the way to go, and the price is falling.

Many of you have probably heard of the RTK tower networks that have been popping up? Set on the highest spot in an area, these network towers usually have a 12-mile radius range and provide the differential signal so that you can be very precise running equipment.

In the past, the portable antenna provided that fixed signal. While those could be expensive, they still have their place. Yet as tower networks grow in number and coverage, more producers are likely to sign up for a subscription. Oh, yes, there's a subscription charge.

GPS is a great tool, but nearly worthless on the farm without a differential signal (we even used to call on-farm systems DGPS or differential). That signal comes for a fixed-location source - like a geo-stationary satellite or a coast guard antenna or a Wide Area Augmentation System tower. For RTK, the precision is higher because that fixed signal is no farther than 12 miles from your machine, and the receiver on the farm gets a better reading.

To get that differential signal - and all higher-precision signals have a fee (WAAS and Coast Guard signals are free, but not as precise) - you pay a subscription for each receiver you have on the farm. Most dealers and service providers with an RTK differential tower network have a fee structure that offers a discount for multiple receivers on one farm. And if you set your receivers up so they can be moved easily, that helps too.

As the winds of winter whip across your farm (and for my warmer-climate readers, as the cooler days appear) it's probably time to consider how you want to maximize GPS technology on your farm. If it's time to move to higher precision equipment operation - for steering or other specialty operations - RTK may be the way to go.

Whether you get that differential signal from a free service, a satellite or the local tower network, start with your dealer first. Service remains an important part of keeping these tools working on your operation and the major-brand dealers have systems in place.


If you missed our Inputs 2010 Webinar, you can catch the replay by visiting farmprogress.com/inputs2010 to listen in.

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