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Honestly, I'm surprised that managed 90Mbps. Beaming internet from satellites iis not really a great idea because you are essentially doubling the wireless band
by slaymaker1907 4y ago
Honestly, I'm surprised that managed 90Mbps. Beaming internet from satellites iis not really a great idea because you are essentially doubling the wireless bandwidth required for a given level of service. Wireless cell service has the big advantage of only needing to use bandwidth for the link from the tower to the client while satellites require a link to the client and a link back to the ground station. There's also the fact that putting a bunch of compute into a satellite is going to be way more expensive due to weight, power and cooling in space not to mention increased cosmic ray interference.
- sgtnoodle 4y agoIt's highly directed radio signals, though, so it's spatially separated.
- ncmncm 4y agoDoesn't help, really.
- sgtnoodle 4y agoSure it does. The most directed RF signal is a wire...
- ncmncm 4y agoNo. A separate wire has its own transceiver. They still have to share the transceiver among all subscribers. Beam forming saves on transmitter power and receiver S/N stats. If it were all just for you, that could improve your bandwidth. But it is not. Lots of people would like you to think otherwise. Now you know better.
- jlokier 4y agoBeamforming phased array MIMO antennae certainly can transmit to and receive from multiple stations via spatially distinct beams in parallel at the same time. I don't know if Starlink satellites do so, but it is technically possible.
- ncmncm 4y agoIf you imagine each gets its own on-board transceiver, I have a bridge with your name on it.
- jlokier 4y agoNo need for a bridge, I have signal processing products with my name on them, thanks. I'm familiar enough with the field to know how such things work. An active multi-peer beamformer uses a single transciever complex using mathematical signal processing to transcieve multiple data channels to peers in parallel. Some types of phased array antenna offer multiple focus points at the same time, but the electrical signals must pass through a transceiver complex for the different components to be combined and separated mathematically. In simplified terms, matrix multiplication is used to transform between parallel data channels and parellel antenna components; then the antenna geometry focuses them approximately into parallel beams. It's not a transceiver per peer, but it behaves a bit like one for the set of focused peers at each time slot. Spatial separation by this method increases aggregate bandwidth, and therefore increases individual peer bandwidth when there is congestion.
- ncmncm 4y agoIn principle you could say each array element has its own transceiver. But the computational load goes up with the number of distinct beams, and tight enough beams to address each subscriber individually would anyway need an array orders of magnitude bigger than the actual satellite. So instead we have binning by solid angle and frequency, and also TDM and software-level addressing. Some of that must be what makes uplink data rate so much lower than downlink. Point is just that practical limits make things rather worse than what a subscriber might naïvely hope for.
- wumpus 4y agoIt appears that every satellite with spot beams does that.