Tower mounts for cell antennas are triangle-shaped mounts that attach to each of the three tower legs. The design looks something like this.
In this drawing, the blue triangle is the tower and the white triangles are the tower mounts. The small blue dots represent antennas. Each tower mount triangle represents a sector of the antenna array. This is illustrative of an average macro cell tower arrangement, three tower mounts, with three antennas on each mount. The sector mounts are named Alpha, Beta, and Gamma (or A, B, and C, if lettered). The sector closest to North is called A or Alpha; the next sector clockwise is B sector or Beta; and the last sector, still going clockwise, is C or Gamma sector.
These sector mounts are getting larger because they have to hold larger antennas and remote radio heads, diplexers, and amplifiers. Because of this, the sector mounts frequently have a stiff arm, tie back arm, or stabilizer arm added that attaches to the face of the mount, and a different tower leg than the mount back is attached. The stabilizer arm, shown here in red, helps prevent the mount from twisting and moving. For simplicity’s sake, I only added one stabilizer arm.
Below are some antenna mount pictures to bring the diagram information to life. Enjoy.