[TML] A little tinkering with Lasers

[shadow at shadowgard.com]

On 25 Aug 2007 at 21:18, Glenn M. Goffin wrote:

> shadow at shadowgard.com replied:
> 
> >Actually it's *not* essentially zero. Otherwise you wouldn't notice 
> >the lag time on a satellite link compared with a cable across the 
> >seafloor.
> >
> >Don't forget that the lower the orbit the two ships are in, the 
> >*farther* out a relay has to be to be able to see both of them.
> 
> gmgoffin at yahoo.com now replies:
> 
> You're right that there is indeed a barely noticeable time lag for
> satellite communications. Is that caused by distance or by copying
> and rebroadcasting the signal?

It's the distance. Transatlantic and transpacific cables, especially 
the older ones do that copy and retransmit process *dozens* of times.
 
> In any event, the point is moot, isn't it?  Each meson communicator
> has to know where the other is for communications to take place.
> Ships in orbit on opposite sides of a planet have to rely on relays
> to find each other.  The time lag caused by using sensor relays is
> the same as the time lag caused by using communications relays.

Actually they only need that if they are manuevering. If they are 
both in stable orbits, they can predict where each other will be 
quite well.

Add a subchannel with "orbit correction" data and they'll be fine 
even if the orbits are a bit off.

> gmgoffin at yahoo.com had written:
> 
> > I wasn't talking about time lag in the context of orbital
> > communications.  I was talking about the time lag in intrasystem
> > communications.  Messages from a meson communicator take just as
> > long to travel from, for example, one planet to another, as
> messages
> > from a laser communicator.  I was referring to that sameness of
> time
> > lag.
> 
> shadow at shadowgard.com replied:
> 
> >I was responding to the *specific* situation mentioned of using
> meson
> >comms between two ship on oppodsite sides of a planet versus EM
> >comms thru a relay "past" the planet.
> 
> I suppose I could have been more clear.  The comment about time lag
> does come immediately after the ship-planet-ship example, but was
> really referring to the first sentence of the paragraph.  Sorry to
> have confused you.

It's ok. Happens all the time on lists.

--
Leonard Erickson (aka shadow)
shadow at shadowgard dot com