Product Specs

Packet Modem Spec Rev6.doc 14 06/09/00
4. GSP 1620 Features:
4.1 Globalstar Satellite Service:
The GSP 1620 offers Full Duplex (FDX) transmit and receive capabilities, at 9.6 Kbps,
via the Globalstar satellite constellation, and utilizes Qualcomm’s CDMA Digital
technology, for signal clarity and reliability.
The Globalstar Air Interface (GAI) is based on a modified (proprietary) IS-95A standard
adapted for Mobile Satellite System (MSS) operations.
• Forward Link (Module Receive): 2484.39 to 2499.15 Mhz
• Reverse Link (Module Transmit): 1610.73 to 1625.49 Mhz
4.2 Packet Data:
Globalstar and the GSP 1620 Satellite Modem offers direct internet
connectivity by bridging the last “thousand” miles air gap using LEO
satellites. The following section describes in detail the capabilities offered by
the GSP 1620 for user connectivity, and data transmission.
4.2.1 Mobile Originated and Mobile Terminated Packet Data:
Allows the Application Device (DTE) connected to the module to originate or receive,
via standard AT commands (see Chapter 4) a “packet data call” and establish a PPP
session, connecting to the Internet, and then establishing a session with a host application
at the far end.
4.2.2 Data Rate: 9.6 Kbps
• Discounting packet data overhead bits, the measured effective “user” throughput (i.e.
customer bearer data) has been measured and averages 7.4Kbps.
4.2.3 TCP/IP with PPP Connectivity
4.2.3.1 Networking Software:
The modem can be controlled using standard AT commands, (listed in Chapter 4) as well
as Standard Networking Software which will establish, manage, and teardown the PPP