Signals are also received via side lobes, an inherent property of the wave-like character of microwaves and the resulting "spreading" in the vision of a dish. Side lobes must be at least 16 to 20 dB lower than the main lobe. This means that a signal intercepted along the side lobes would be detected at 16 to 20 dB below the power that it would have been if it entered along the dish boresight. Side lobes "see" off-target signals that consist of unwanted noise and interference from adjacent satellites and other communicators.r C-band and Ku-band dishes up to roughly 5 meters and 3 meters, respectively, experience shows that a prime focus feed system results in better efficiency and lower side lobes at dramatically lower costs. However, for larger dishes a Cassegrain configuration has the advantage that the feed is in a much more accessible and serviceable location.