Globalstar STINGR User Manual page 6

Revision 1.0 STINGR Users Manual
Figure 3 Simplex Messaging
Messages are composed of 1 or more 9-byte payloads. The STINGR can only transmit 9-byte on-air messages, so user
payloads greater than 9 bytes will require multiple on-air packets to be transmitted for each user payload.
There are brief periods of time where there is no satellite in range of the simplex transmitters due to obstructions
and/or satellite coverage geometry. Since a simplex device has no way of knowing if a transmitted message has been
successfully received, the STINGR device is designed to send multiple (redundant) transmissions for each message being
sent over the Globalstar network. The default value for the number of redundant transmissions per message is 3. This
means that each message sent to the STINGR will be transmitted 3 times. Each transmission will contain the exact same
data payload. The redundant transmissions of each message will be sent on a randomized 5-minute nominal interval.
The transmission sequence for a single-packet message using the default setting of 3 redundant transmissions is shown
below.
Revision 1.0 Subject To Change without Notice P a g e | 6
09/30/15