Trimble pioneered RTK in the early 1990s as a means of delivering high accuracy corrections for field applications. In the two decades since, RTK has become the industry leading methodology for sub-inch positioning. Traditional RTK uses radio communications to provide corrections. When using RTK with radio communications, you need access to a base station located within a eight-mile radius (approximately) from your farm. An RTK base station sends corrections via a radio transmitter to a mobile receiver attached to your vehicle.