Selecting the right technology for a project is often dictated by accuracy requirements, with GNSS and Total Station being common choices. However, certain projects require the convenience and speed of GNSS, despite challenges like high multipath or dense overhead canopy.

Traversing through thick bush with limited line of sight can be slow and budget-challenging. Leica’s Multi-frequency GNSS solutions offer a breakthrough, allowing for the completion of more tasks using GNSS in scenarios where RTK accuracy is acceptable.

This doesn’t mean GNSS is the right tool for every job… but it does mean that for previously inaccessible or cost prohibitive sites, GNSS may be able to provide us with actionable data!

“As a practical exercise, I took a Leica GS18 into a heavily bush-clad area of Christchurch’s hill suburbs to relocate some existing pegs.  My natural scepticism firmly in place, I was surprised and excited to re-measure these pegs within 2-3 cm in position and 3-5cm in height.  The availability of GNSS RTK in this steep vegetated environment would have been suitable for many survey applications and given that a total station would have lost line of sight within 5m in most areas, it was far more efficient than any other ground-based solution”  Richard Harrison – Global Survey

Leica introduced advanced RTK Multipath algorithms in Captivate v6.50, continually refining the technology since. These algorithms are particularly effective for lower frequency GNSS signals (L5, E5, E6, B2, B3). In trials with high multipath environments, there has been a notable up to 60% reduction in code range multipath error, directly translating to improved RTK performance.

For more in-depth information, you can refer to the paper “Improved high-precision RTK positioning through multipath reduction and interference mitigation” by Miguel GONZÁLEZ-CALVO, Xiaoguang LUO, José Amado APONTE, and Bernhard RICHTER, presented at the FIG Congress 2022 in Switzerland.

Improved GNSS multipath reduction is crucial for enhancing the accuracy of RTK solutions. While code range observables may not be the first thing that comes to mind in RTK discussions, they play a vital role in achieving precise RTK carrier phase initialization. Addressing code range multipath errors significantly boosts RTK availability without compromising reliability or accuracy.

This enhancement is applicable to multi-frequency rover GNSS devices like the GS18, GS16, and GS15, as well as the multi-frequency reference stations integral to the SmartFix network.

Leica’s Multi-frequency GNSS solutions enhance your efficiency in challenging environments. By addressing GNSS multipath challenges and improving RTK performance, these technologies open doors to a wider range of applications where GNSS was previously impractical. Whether you’re navigating dense vegetation or dealing with overhead obstructions, exploring multi-frequency technologies could revolutionize your surveying approach.

Talk to us to discover how  you can utilise these new multi-frequency technologies by getting in touch with the team:  on 0800 453 422 or email info@globalsurvey.co.nz