khalil
no
in a deep fringe area, we may combine similar antennas to receive a tv channwl,...
on the roof antennas we know their phase angles but do not for indoor antennas ...
because they receive reflected signals...unknown phase angles
spacemissing
No, it is not feasible.
If you could manage (and it would be Very difficult in practical terms)
to "co-phase" two or four directional indoor antennas and aim them properly,
you might end up with a minimal improvement,
possibly as much as 3 dB with two or 6dB with four.
That is probably nowhere near enough.
Most indoor antennas are Not directional and therefore cannot be co-phased.
Installing a single outdoor antenna with sufficient gain to do the job
would be a lot easier.