5 ms·
Is there any decent resource explaining how the whole mesh of Starlink sattelites communicate to each others and to the ground ? Do they use RF radio or modulat
by ruslan 6y ago
Is there any decent resource explaining how the whole mesh of Starlink sattelites communicate to each others and to the ground ? Do they use RF radio or modulated laser ? What equipment should be used by end users and what frequency range ?
- modeless 6y agoDetails are here: https://licensing.fcc.gov/myibfs/download.do?attachment_key=2378669 https://licensing.fcc.gov/myibfs/download.do?attachment_key=... TL;DR User terminals are RF phased array antennas. Ka-band and Ku-band, plus E-band for ground stations. v1 has no cross satellite links. Plans for v2 include laser cross links.
- ruslan 6y agoOk, thanks. Designing a DYI terminal won't be easy for these bands.
- mNovak 6y agoThe user terminals in the current generation are Ku only; Ka is reserved for the gateways. Interesting, the picture on reddit above--those don't look like phased arrays to me.
- shaklee3 6y agoThey could be phased array under a radome.
- ruslan 6y agoAFAIK, those are regular dishes with tracking system. Phased arrays do not require mechanical tracking as they use phase shift to direct radiation.
- shaklee3 6y agoSpaceX phased antennas are both phased arrays and mechanical steering since they are lowering cost by decreasing the scan angle of the phased array.
- ruslan 6y agoFrom my point reducing electronics while adding more mechanical parts will most likely lead to both cost and size increase which will make product less attractive. Fast FPGAs are getting cheaper daily.
- mcpherrinm 6y agohttps://www.reddit.com/r/Starlink/comments/gknla6/this_looks_like_3_ufos_on_a_stick_with_a_small/ https://www.reddit.com/r/Starlink/comments/gknla6/this_looks... Photos here of a starlink ground station with three small devices that are quite possibly the end-user equipment.
- shaklee3 6y agoThose radomes are extremely expensive. If that's the user terminal then it's going to be quite a bit more expensive than any consumer service.
- Dylan16807 6y agoHuh? The radomes are not the three small devices in that image.
- shaklee3 6y agoI was referring to what appears to be the gateways. If the smaller one is the CPE I'd be curious to see where the motor is, and how it will be prevented from weathering/failing.
- walrus01 6y agoThose are the trunk link earth stations. Not the CPEs. To be pedantic the radomes are only a couple of thousand dollars each, it's what's inside them that's expensive. Spherical radomes up to a couple of meters in size are kind of a commodity item. The Cobham-manufactured, agile, ku-band tracking dish antennas with Rx+Tx RF chains are expensive. The small white things not in radomes shown in the picture are possibly beta test CPEs.
- shaklee3 6y agoRight, sorry. I was referring to the large white ball. Ka/Ku radomes are not cheap. The only information on antenna size is from Elon saying it's the size of a pizza box. Those look too small to be the CPE (imo).