# SBAS

Satellite‑based augmentation system (SBAS) signals provide real‑time, differentially corrected positions without the need for a radio link. You can use SBAS in real‑time surveys when the ground‑based radio link is down.

To use SBAS signals, in the Rover options screen of your survey style, set Satellite differential to SBAS. In real‑time differential surveys, you can set the broadcast format to SBAS to always store SBAS positions without the need for a radio link.

For real‑time differential surveys where the rover can track the QZSS signals, select SBAS in the Broadcast format field, and select the QZSS option. This enables the rover receiver to track the QZSS satellite and, if you are within the valid QZSS differential network, to use the QZSS SBAS differential corrections in the real‑time differential survey.

When SBAS signals are being received, the radio icon changes to an SBAS icon , and in an RTK survey, RTK:SBAS is displayed on the status line.

In an SBAS survey, QC1 quality control information is available, while QC2 and QC3 are not available.

The availability of SBAS signals depends on your location. For example:

- WAAS is available in the Americas.
- EGNOS is available in Europe.
- MSAS and QZSS are available in Japan.