User's Manual

Iridium Communications, Inc. Information Contained in this Guide
Iridium Core 9523/9523N Product Developer’s Guide is Subject to Change Without Notice
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4.3 Radio Characteristics
Table 17 contains radio characteristics of the Iridium Core 9523/9523N.
Table 17: Radio Characteristics
Parameter
Value
Average Power during a transmit slot (max)
7 W
Average Power during a frame (typical)
0.6 W
Receiver sensitivity (Typical level at connector)
-118 dBm
Max Cable loss permitted (Note 1)
3 dB
Link Margin – Downlink (Note 2)
12 dB
Link Margin – Uplink (Note 2)
12 dB
Note 1: Cable losses should be minimized. The total implementation loss for an antenna, connectors,
cable, lightning arrestor and any other RF component between the Iridium Core 9523/9523N and the
antenna should not exceed 3 dB. Implementation loss higher than this will affect the Iridium link
performance and quality of service. Solutions with a loss higher than 3 dB will not meet the requirements
of Iridium Solution Certification.
Note 2: Link Margins are given assuming a free-space propagation model.
4.4 S-meter Performance
The numbers reported over the AT command interface indicate the signal strength of the ring channel.
Care should be taken when using the S-meter readings for comparisons between devices. Of particular
note are the following:
1. There is a 0.5 dB tolerance on calibrating the S-meter.
2. Each bar represents a 2 dB increment.
3. Multiple ring channels can be present at the same time so units can lock to different signals.
4. If the reading is near the decision threshold it would be easy to see a 1 bar difference.
5 AT Interface
The Iridium Core 9523/9523N is configured and operated through the use of AT commands. See the ISU
AT Command Reference for the full set of AT commands and responses. For differences in AT command
support between Iridium Core 9523/9523N software releases, see the relevant software release notes,
which are made available to authorized Iridium VARs and VAMs on the Iridium Developer Extranet. It is
the responsibility of Product Developers to check compatibility of applications software with the AT
Commands on all Iridium Core 9523/9523N software versions used for both development and commercial
deployments.