Digi M10 Gateway Earth Station GES, Subscriber Communicator SC, SC Terminated, SC Originated

Digi m10 Technical Overview

3.2Gateway Earth Station (GES)

The role of the Gateway Earth Station (GES) is to provide an RF communications link between the message switch and the satellite constellation. It consists of medium gain tracking antennas, RF and modem equipment, and communications hardware and software for sending and receiving data packets. The GES equipment and site are designed for unattended operation. The GES uses radome-enclosed, VHF full-motion antennas with approximately 17 dB of gain. Two fully independent antenna systems, and associated RF and control equipment, provide complete functional redundancy at a GES site.

3.3Subscriber Communicator (SC)

The term Subscriber Communicator (SC) refers in general to the satellite modem or a device incorporating a satellite modem.

3.4SC Terminated

Messages sent to the SC from the GES

More documentation can be found on the kit installation CD. To learn more, navigate to C:\Program Files\Digi\Digi m10 JumpStart Kit\documents please refer to either ORBCOMM Serial Interface Specification > SC-TERMINATED MESSAGE or ORBCOMM Serial Interface Specification > Figure 4.8 SC-Terminated Message.

3.5SC Originated

Messages sent from the SC to the GES

More documentation can be found on the kit installation CD. To learn more, navigate to C:\Program Files\Digi\Digi m10 JumpStart Kit\documents please refer to either ORBCOMM Serial Interface Specification > SC-ORIGINATED MESSAGE or ORBCOMM Serial Interface Specification > SC-ORIGINATED MESSAGE.

3.6Global Gram

Global Gram messaging, or store-and-forward message transfer, is available in instances when a satellite is in view of a satellite modem, also referred to as Subscriber Communicator (SC), but there are no ORBCOMM gateways connected to the satellite. Examples of such instances include ocean areas and locations where there is no gateway, but regulatory approval for a satellite modem to communicate with a satellite has been granted. Global Grams allow satellites and satellite modems to archive short messages when the destination ORBCOMM gateway is

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