All satellite dishes incorporate a parabolic curve into the design of their bowl-shaped reflectors.
The parabolic curve has the property of reflecting all incident rays arriving along the reflector's axis of symmetry to a common focus located to the front and center. The parabolic antenna's ability to amplify signals is primarily governed by the accuracy of this parabolic curve. Poor antenna performance can result from inaccuracies in the dies used to manufacture the reflector surfaces. More often, however, low antenna efficiencies are caused by the installer's failure to grasp the importance of using good antenna assembly techniques. The reflector must be constructed out of metal in order to reflect the incoming microwave signals.