Re:SpaceX sends laser-linked Starlinks to the polar orbit
by walrus01 on Monday January 25, 2021 @03:32PM
(#25908391)
the starlink beta test customer terminals only have a cone shaped view of suitable beam forming ability and gain above them, so the 4000 km is a lot less in usable practice. they can't talk to a satellite that's 15-20 degrees above the horizon for instance, it'll only work when the satellite rises higher in its general field of view.
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Re:SpaceX sends laser-linked Starlinks to the polar orbit
by namibj on Monday January 25, 2021 @10:59PM
(#25912355)
The horizon limitation is primarily regulatory.
Given that limitation, it doesn't make sense for them to extend the cone closer to the horizon than their flat phased array can do.
Re:SpaceX sends laser-linked Starlinks to the polar orbit
by shaklee3 on Tuesday January 26, 2021 @12:38AM
(#25912933)
Not true. The antenna itself has a very low scan to keep costs down.
Re:SpaceX sends laser-linked Starlinks to the polar orbit
by namibj on Tuesday January 26, 2021 @01:02AM
(#25913054)
Yes, because e.g. a multi-panel design would be limited by regulations. Hence they decided on the single panel for ROI/cost-efficiency purposes.
Re:SpaceX sends laser-linked Starlinks to the polar orbit
by walrus01 on Tuesday January 26, 2021 @12:59AM
(#25913040)
Indeed, a flat phased array can only have a certain limited gain at elevations and azimuths far away from the direction it's pointed in. One of the reasons if you ever see a flat phased array radar inside the nose radome of a air superiority type fighter jet, they're not fixed but also can be mounted on a sort of pan/tilt platform for steering.