Re: How many satellites are in geosynchronous orbit by now?

Am Fri, 9 Dec 2005 20:15:31 GMT schrieb "Henry Spencer":

>Third, when you start talking about seriously long ranges, radar search
>becomes a three-dimensional problem, not a two-dimensional one, because
>you must point in each direction long enough for an echo to come back from
>an uncertain distance. For example, if you want to search out to lunar
>distances, you cannot change direction more often than about once every
>three seconds, because it takes that long for an outbound pulse to travel
>out to that distance and an echo to come back. Even for GSO, where the
>round trip is about 1/4 second, this issue isn't trivial.
>[...]

What about a transmitter with a bit larger beam width, and a coded
pulse pattern, then an array of somewhat narrower beamed receivers
following the sender's track. Given the ability to identify, which of
the transmitter's pulses was received (by decoding), you can cover a
relatively large area, even three-dimensionally over large ranges...

cu, ZiLi aka HKZL (Heinrich Zinndorf-Linker)
--
"Abusus non tollit usum" - Latin: Abuse is no argument against proper use.

mailto: heinrich@xxxxxxx http://zili.de
.