Path to Precision

This ONE thing is the key to getting accurate measurement and control on your farm

26 Nov 2021

Before we go diving into the why and how behind GNSS, it is important to understand exactly what GNSS is?

GNSS stands for 'Global Navigation Satellite System' and it's this very system that allows your handheld mobile device or your car's built-in sat-nav to determine your location, pretty much anywhere in the world!

When we refer to 'GNSS' we are actually referring to multiple constellations (groups) of satellites that are in orbit around Earth today. Some primary examples of GNSS constellations used today:

  • GPS – a US constellation
  • GLONASS – the Russian Constellation
  • Galileo – European-owned constellation
  • BeiDou (COMPASS) – Chinese constellation

With some advanced computation, radio frequencies, expensive atomic clocks, and 'error correction' algorithms, GNSS allows us position accuracies of less than 2cm in agriculture. Let's repeat that: less than 2cm!

So a bunch of satellites orbiting Earth, being able to pinpoint our position very accurately. Sounds pretty high-tech, but what does this have to do with agriculture? Well GNSS in agriculture is responsible for some of (if not the MOST) efficient practices in agriculture today.

How? It's a two-fold approach:

  1. 1. GNSS allows you to MEASURE site-specifically. i.e. If your yield is particularly bad in one area, GNSS shows you where! Or if your soil conditions aren't optimal in another area, GNSS shows you where! Once you connect your previously mentioned sensors to a GNSS position you can start to draw deeper insights into the very things you are battling against in agriculture - variability! And this ultimately leads to better decisions.

  2. 2. So now you can see now see the variability in your fields. Now what? Well this is where GNSS technology comes into its own. GNSS also allows you to now CONTROL site-specifically. It's this level of control that has enabled farmers to be more prosperous than ever before. To do more with less. You can now treat your field and crops in accordance with their variability. You can reduce skips and overlaps, minimise crop damage and save on the input costs of every other farm commodity through this level of GNSS control. We'll dive into control technologies in later articles.

What do YOU need in order to use GNSS on your farm?

The answer to this question can vary depending on what you want to achieve. Is it just for measuring? Control? Both? We'll aim to simplify this question in further articles, but in its most basic form you need:

  1. 1. A receiver

...yup that's it! A receiver, installed to your machine or equipment, allows you to measure any supported sensor and control any supported control technology site-specifically.

Of course, like most products, you can get low cost, low spec receivers and high cost, high spec receivers. On their own they are capable of sub-meter accuracy... i.e. sub-meter measurement and control.

In some applications this is enough. In others, you need something even more accurate. We've already said GNSS in agriculture is capable of accuracy down to less than 2cm. In order to achieve this, a standard receiver requires an additional error correction source.

Error correction is exactly that – another source that is correcting the errors in a standard GNSS receiver signal. This can be satellite based or ground based. See future posts to learn more error correction.

In summary, GNSS is the primary component to give farmers back much more control over their never-ending battle against variability. GNSS and sensors together are to the field what an MRI is to the human body: it can scan for any problems and identify areas that need intervention. And like in human bodies, a prescription to treat any problems is required. We'll cover how this is done in the next posts on farm management software and control.