Present Satellite Systems

The follow table is extracted from the material in the web document entitled Technology Assessment of Mobile Satellite System Alternatives prepared by the United States Coast Guard, Research and Deveopment Center, Advanced Communications Technology Project, LCDR Gregory W. Johson, Mr. Jon Turban, and ETCS Robert Erickson, April 1998.

This table compares current data and/or voice satellite communications systems


Argos Inmarsat A Inmarsat B Inmarsat C Inmarsat M Inmarsat
Mini-M
BOATRACS AMSC DirecPC
Service Type Data Only Analog
Voice/Data
Digital
Voice/Data
Data, FAX Digital
Voice/Data
Digital
Voice/Data
Data Only Digital
Voice/Data
Data Only
System Type LEO GEO GEO GEO GEO GEO GEO GEO GEO
Coverage Worldwide Worldwide Worldwide Worldwide Worldwide Worldwide CONUS+
200-400NM
offshore
CONUS+ 200
NM, AK, HI
CONUS
Frequency
Band
UHF L L L L L Ku L Ku
Data Rate 1200bps
(256 bit
bursts)
(inbound)
9600bps* or
56kbps
9600bps* or
64kbps
600bps
(1200bps
repeated
32Kbyte
max message
2400bps 2400bps 600bps 4800bps 400kbps
(outbound)
Terminal Cost Varies,
depending
upon size
and
complexity
$25,000-
$35,000
$25,000-
$35,000
$2,000 $10,000-
$12,000
$5,000 $4,000 $2,500 $300
Monthly Cost Negotiated $0 $0 $0 $0 $0 $40 $25 $10-$130
Usage Cost Negotiated $3-$8/min $2-$6/min 1¢/char $2-$6/min $3/min .4¢/char plus
50¢/msg
$1.50/min $3.95-$4.95/hour
Antena
Type/Size
Small whip 1m tracking 1m tracking 0.24m
omni
0.6m tracking 0.2m tracking 0.3m" az tracking 1m whip, .3m
tracking, .6m
tracking
.6m fixed dish
Year
Operational
1978 1982 1993 1992 1992 1996 1989 1996 1997
*Speed of Inmarsat A connection depends upon type of modem used, signal strength, and channel quality.
This is also RAW speed. Most modems incorporate V.42/MNP compression.

Note that terminal cost, monthly cost and usage cost may change and may be negotiated.


Last modified: July 27, 1998