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Wavecom W-SPECTRA (Automatic Monitoring System) V1.1.0 User Manual

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Transmission Modes

WAVECOM Monitoring System W-SPECTRA, W-SPEED Manual V1.1.0

Protocol Structure

System Information

Network and system information is transmitted within the system subdivision of a batch. The system in-
formation is divided into two parts, System Information (SI) and Supplementary System Information
(SSI).

Depending on the value of the SSI flag the Supplementary System Information (SSI) carries information
on zone, local time and date. Another option displays day of week, month of year and year.

Data

ERMES transmits data in fixed-length frames of 36 bits. A frame may carry an additional data field and the
text data.

Message Frame (MHEAD)

The Variable Information Field (VIF) has two main options depending of the status bit ALL = 0 or ALL = 1.

Variable Information Field Without Supplementary Information

Variable Information Field With Supplementary Information

The ETS 300 133-4 standard has a very fine grained subdivision of the VIF and this enables ERMES to be
used for a wide range of applications.