Mark Wolfe wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > At sea systems get into $$$$, you have to track the satellite. Boats > tend to pitch, roll and yaw. So, in order to compensate for this, and > keep your antenna locked on a bird, you need to detect movement of the > ship. Most the commercial stuff I've worked with has had a small > roll/pitch gyro in it, and took heading from the ships compass. They > fed all this to a computer which then positioned the antenna. These > systems run the cost of a nice car, but you get TV at sea. Inmarsat is > the same. With our systems we'd get 64kbit and it would run around 8 > bucks a minute. Not sure with the new iridium stuff, but I still > imagine it will be expensive. Again, still got to compensate for ships > movement. You won't see them on small craft, as it's too cost > prohibitive. For good signal strength, you'd need about a 1 meter dish, > then you'd need to protect it with a radome. These things take up room, > and there's not much above deck space on a sub 40 foot boat for one.
Given all of the above, how does an Iridium satellite phone send and receive digital voice with a satellite without any of the above fancy machinery? And it must do it at around 64kb/s minus compression since it transmits voice. -- Tracy R Reed http://copilotconsulting.com 1-877-MY-COPILOT -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
