RCB-F9T - Integration manual
Figure 15: GLONASS navigation message data
In some circumstances, (especially on startup) the receiver may be able to decode data from a
GLONASS satellite before it can identify it. When this occurs UBX-RXM-SFRBX messages will be
issued with an svId of 255 to indicate "unknown".
3.12.1.4 BeiDou
For BeiDou signals there is a fairly straightforward mapping between the reported subframe and the
structure of subframe and words described in the BeiDou ICD. Each subframe comprises ten data
words, which are reported in the same order they are received.
Each word is arranged as follows:
Figure 16: BeiDou subframe word
Note that as the BeiDou data words only comprise 30 bits, the 2 most significant bits in each word
reported by UBX-RXM-SFRBX are padding and should be ignored.
3.12.1.5 Galileo
The Galileo E1-B and E5b in-phase signals transmit the I/NAV data message but in different
configurations to enhance down-load time for dual frequency receivers. The UBX-RXM-SFRBX
structure for the I/NAV message is shown below.
UBX-22004121 - R01
3 Receiver functionality
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C1-Public
Early production information
