Commercial Space Flight General / Re: Communications Services Project: commercial successor to TDRSS« Last post by DanClemmensen on Today at 06:26 pm »
Yes, of course, gimbals are required even for coplanar satellites.If the slew rate is "very high", then you should not attempt to establish an ISL. Pick a satellite that is farther away or is moving in a more appropriate direction.
The issue arises when there is a user in a different plane and a different altitude. Depending on the relative positions of the satellite and the user, the slew rate of the gimbals may be very high.
Also, apart from generally pointing the user receiver upwards, where do the user ISR(s) affix to the spacecraft?
One popular theoretical approach is to place your major networking satellites at a higher altitude. the usual lower-altitude satellites connect in rings, one per orbit, and several satellites in each ring connect up to the higher "network". The satellites in the "network" do not serve terrestrial users, but they have lots of ISL with each other.