Life beyond traditional RTK: Satellite based Precise Point Positioning

Many measurement professionals can find themselves in situations where there is no local reference network. What can they do? The answer is Precise Point Positioning (PPP).

The foundation of Leica Geosystems GNSS technology is RTKplus and SmartLink - the PPP solution, which complements the traditional RTK method. Using a self-learning GNSS sensor, like the Leica Viva GS16, you can be sure that your sensor adapts to predominant conditions. It will use the most relevant satellite signals and provide you automatically the best available position.

The GNSS infrastructure of the RTK technology, which enables us to perform precise and efficient positioning, does have challenges in its theoretical basis. Consider this: in addition to satellites, RTK also needs a network of permanent stations and services, or our own reference station, mobile cellular network service, or the use of our own radio transceiver.

How many times do we need to make measurements in places where the mobile cell service is weak or unavailable? Or in the field, in spite of the increasing number of satellites, we need more of them? It has happened before and will continue to happen that due to technical issues, manpower shortages or financial reasons, a network service is not available or not available in the appropriate quality, temporarily or for a longer period of time. What happens in situations in which we need to make measurements in places where there is no local reference network at all?

These are all questions that perhaps do not apply to daily, average situations, yet they do occur frequently that ensure a competitive advantage for the user.

The constantly evolving technology of PPP provides an auxiliary solution problem like this, and in the case of Leica Geosystems, it is realised in SmartLink and SmartLink fill services.

What is SmartLink?

SmartLink is a GNSS correction service where data is transmitted by satellites.

The quality of the position in this case will be like this:

Naturally, the situation above assumes that the auxiliary satellites are visible.

What is SmartLink fill?

SmartLink fill is also a GNSS correction service where data is transmitted by satellites, but it can bridge an RTK outage and retain a position to centimeter level accuracy for up to 10 minutes.

The quality of the position in this case will be like this:

Obviously, if the reception of RTK correction returns within 10 minutes, then we can anticipate RTK accuracy again. Naturally, the situation above presumes that the auxiliary satellites are visible.

What are the benefits of this service for the users?

• Are you measuring in a distant place where there is no network of reference points, and, accordingly, no RTK network service? Additionally, there is no opportunity for creating your own network based on a lengthy and costly post-processing? With SmartLink, you can start surveying within 30 minutes with ±3 cm 2D accuracy.
• Are you working in a field where there is RTK correction due to cell phone interruptions? Despite this, would you like to continue doing your job with centimetre-level accuracy without stopping and without RTK corrections, for any length of time? SmartLink is the solution.
• Are you working in a place where there is an RTK correction, but it is not available for some reason? Despite this, would you like to continue doing your job with centimeter-level accuracy without stopping and without RTK corrections for a temporary period of time (approx. 10 minutes)? SmartLink Fill is the solution.

To learn more about SmartLink services, please contact your local Leica Geosystems representative.