Mount the antenna unit so that any blind sectors caused by objects (mast, etc.) are kept
to a minimum. No blind sector should exist in arc of the horizon from right ahead to 22.5°
aft of the beam to either side (see Figure 1 below). Also, individual blind sectors of more
than 5°, or the total arc of both blind sectors of more than 20°, should not occur in the
remaining arc (Figure 2). Note that any two blind sectors separated by 3° or less are
regarded as one sector.