Your GNSS operations are only as good as your correction source, it’s important to choose the right one for your business.
Use the technical specifications below to decide on the source that makes sense for your workflow and performance and precision requirements.
| GNSS Correction Source | SPS GNSS Precision | Delivery | Initialisation |
|---|---|---|---|
| Trimble GNSS RTK Base |
H 0.8 cm (0.026’) + 1 ppm V 1.5 cm (0.05’) + 1 ppm |
UHF, WiFi, IBSS | < 8 seconds |
| VRS Now |
H 0.8 cm (0.026’) + 0.5 ppm V 1.5 cm (0.05’) + 0.5 ppm |
Internet | < 8 seconds |
| CenterPoint RTX |
H < 2 cm (0.066’) V < 5 cm (0.16’) |
Satellite, Internet |
< 1 minute (Fast) < 15 minutes (Standard) |
| MSK Beacon / DGNSS |
H 30 cm (1’) + 1 ppm V 50 cm (1.6’) + 1 ppm |
300 kHz Beacon | N/A |
| DGNSS |
H 30 cm (1’) + 1 ppm V 50 cm (1.6’) + 1 ppm |
UHF, WiFi, IBSS | N/A |
| SBAS |
H < 50 cm (1.6’) V < 85 cm (2.8’) |
Satellite | N/A |
If you are running a large operation with many machines, you will need a local GNSS base station (or a few) and if you are site surveying or doing reconnaissance you may opt for a high accuracy satellite delivered service such as CenterPoint RTX.
For larger construction sites and those that include both site positioning and machine control operations, we recommend you deploy the Trimble R750 GNSS Modular Receiver as a permanent or semi-permanent base station.
For additional information on which external antenna to choose for your base station, please visit the Trimble GNSS Antennas for Construction web page, or contact your SITECH Technology Provider or Trimble Marine Dealer.
Trimble VRS Now is a Network RTK subscription service delivered via the internet over a cellular network. Like mobile satellite services (MSS) services, VRS Now is ideal for construction sites where it is not practical to set up a base station, such as sites where there is no machine control or for initial reconnaissance tasks where a base station is not yet established.
VRS Now requires an internet connection at the rover. Utilising Trimble VRS technology, centimeter level accuracy is available on demand, anywhere within the reference station network. It is highly cost effective and efficient, convenient, simple to use, and best of all it’s always on.
VRS Now is a Trimble operated VRS network. To select the service that best suits your needs, please view the Trimble Positioning Services website.
CenterPoint RTX is the premier mobile satellite services (MSS) technology delivering VRS-level performance for land-based construction sites worldwide, 24 hours a day, 365 days a year.
MSS is delivered via geo-stationary L-band satellites. The signal is received at the GNSS rover by the Trimble GNSS Antenna or GNSS Smart Antenna, so there is no need for a UHF radio or cellular network connection.
To select the service that best suits your needs, please view the Trimble Positioning Services website.
Trimble xFill runs seamlessly in the background, automatically bridging the gap if a user’s Real-Time Kinematic (RTK) or VRS correction source is interrupted due to cellular signal disruption or loss of UHF radio connectivity. Trimble xFill is a satellite-delivered service that will maintain RTK precision for five minutes after the loss of an RTK correction stream.
Trimble Internet Base Station Service (IBSS) broadcasts Real-Time Kinematic (RTK) data or Differential (DGNSS) corrections from your base station over the internet via Wi-Fi or a cellular network. This makes it easier and more economical to use high precision GNSS for site positioning or machine control on the construction site over ranges which exceed the limitation of the UHF radio link. IBSS can also be used to augment UHF in areas of poor UHF coverage.
MSK Beacon refers to a DGNSS or DGPS reference stations maintained mostly by the International Association of Marine Aids to Navigation and Lighthouse Authorities (formerly IALA) which transmit a free differential correction service on the 300 kHz band. Trimble marine GPS/GNSS receivers with the appropriate MSK capable antenna can use these corrections at no cost for sub-meter positioning.
The Satellite-Based Augmentation System (SBAS) is based on GNSS measurements from accurately-located reference stations deployed across an entire continent. The differential corrections and integrity messages are broadcast over a continent using geostationary satellites as an augmentation or overlay of the original GNSS message. Systems in place delivering corrections at no cost for sub-meter positioning are:
Marine construction presents its own unique challenges and requirements. No matter how complex your project, Trimble has marine construction hardware, software and positioning sensors to help you meet and exceed them.
Save time, money and headaches with the Trimble R750 GNSS Modular Receiver, Trimble’s reliable, easy-to-use base station solution. With remote monitoring and alerts, an internal radio, LTE modem and rover capability, the R750 is designed to meet all your needs.
A user-friendly augmented reality system used for communicating new designs and changes to field crews, inspections, determining productivity and calculating quick measurements on site including points, lines and cut/fill values.
Fully capable GNSS receiver featuring proven Trimble quality and accuracy priced for a faster return on investment.
