PUMA T2
Technical Handbook
General information
P/N: 779-0306/01
Revision 03
OTE Proprietary information
Page 13
1.5 DATA CALLS
1.5.1 Circuit Data Services
Circuit data service is a feature allowing a user to transfer a virtually unlimited
amount of data to an individual or group identifier.
The circuit data service employs traffic channels to establish a switched connection
among the users.
Different data rates are available according to the option of data protection (TETRA
coding) required. The following are the achievable speeds for each slot:
• 2.4 kbit/s high data protection
• 4.8 kbit/s low data protection
• 7.2 kbit/s no data protection.
The use of a multi-slot service can involve up to four slots circuit data. The
connection may only be half-duplex.
The equipment shall support single-slot circuit mode data communication in full-
duplex mode. Both protected and unprotected data shall be supported with the
following bit rates:
• 2.4 kbit/s high data protection
• 4.8 kbit/s low data protection
• 7.2 kbit/s no data protection.
During the circuit call set-up, the selected speed and use of data protection must
be specified.
1.5.2 Short Data Service
This feature allows a user to transfer limited amounts of data to an individual or
group identifier over the control channel.
Both status messages and short data messages can be sent to/by users already
involved in a speech call or circuit data call (individual or group call). The
messages are routed over control channels associated with the traffic channels
used by the on-going calls.
Short data services are classified as
• Pre-defined (status messages) or
• User-defined (short data messages).
Both services are available between TETRA users (mobile radios and
dispatchers).
Status messages are pre-defined bit configurations known to both users and the
system.
To Next Page
Loading...