Because of the large wavelength you will probably not be able to set up an antenna farm of verticals that are phased together. The next best thing would be a loop antenna which had two nulls. You could then mechanically rotate the loop to point the nulls in the desired direction.
thanks.I have a multiple-arm conical log-spiral antennas which now have three mode.and I also design a feed network to match it.now i want to make it's field pattern steerable.do you think it is impossible?can the loop antenna array reliaze three mode?