NEO-D9C - Integration manual
2 System description
2.1 Overview
The NEO-D9C receiver supports the QZSS L6 signals, QZSS Centimeter Level Augmentation
Service (CLAS) and experimental MADOCA service. The QZSS CLAS service provides high-accuracy
augmentation to GNSS receivers. The CLAS service is available over mainland Japan for free.
Combined with other products from u-blox, NEO-D9C builds a complete and stand-alone high
precision system providing users with access to free high-accuracy correction services and
ultimately centimeter-level GNSS accuracy.
2.1.1 QZSS L6 augmentation service
The QZSS L6 signal is available on satellites in a Quasi-Zenith Orbit over the Asia-Pacific region and
in geosynchronous orbit above Indonesia.
The QZSS L6 is a signal for augmentation corrections. It is transmitted at a frequency of 1278.75
MHz in the L6/E6 band. This signal provides two systems for corrections:
• CLAS: Centimetre Level Augmentation Service
• MADOCA: Multi-GNSS Advanced Demonstration Tool for Orbit and Clock Analysis
The CLAS service is targeted for less than 10 cm performance while MADOCA is a decimeter
correction service. Both these services are SSR corrections services that provide corrections that
are usable for a much larger area than what can be provided with the standard OSR corrections such
as VRS.
Figure 1: QZSS coverage area - image QZSS Japan
UBX-21031631 - R02
2 System description
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