I have eight antennas combined in 7 ANC-4's.

If you use the two serious antenna approach, you simply steer a null
onto the noise source. Unless the desired signal is in the same
direction, it's not cancelled.

Depending on the separation and orientation of the array, it may even
be enhanced (in a peak of the pattern of the phased pair) while the
noise is eliminated (in a null of the pattern of the phased pair).

Generally a quarter wave of separation is good, giving you a peak
at one endfire while you have a null at the other endfire. In general
the null will be a V pattern that you sweep from one endfire, opening
up at broadside to a line, and closing at the other endfire, as you
tune the phasing and gain.

And more generally than noise sources, you can cancel out a local
broadcaster and listen to what's under it, by steering your null onto
him, though it can be a tricky adjustment, since you need an insanely
deep null, so you're dealing in fractions of a degree.

--
Ron Hardin


On the internet, nobody knows you're a jerk.