APPARATUS AND METHOD FOR ALIGNING A RECEIVING ANTENNA UTILIZING AN AUDIBLE TONE

摘要

A satellite receiver for digitally encoded television signals includes apparatus for generating a signal indicating the alignment of the receiving antenna which is responsive to the number of errors contained in the digitally encoded television signals. The antenna alignment signal has the form of an audio signal which is coupled to sound reproducing device associated with the satellite receiver. The audio signal corresponds to a continuous tone when the number of errors is less than a predetermined threshold indicating that error correction is possible. The elevation of the antenna is set according with the location of the receiving site. Thereafter, the azimuth of the antenna is coarsely aligned by first rotating the antenna in small increments so locate a region in which the continuous tone is produced. During this coarse alignment procedure, the tuner of the satellite receiver attempts to locate a tuning frequency at which and demodulation and error correction is possible. If no appropriate frequency is found after a range of frequencies have been searched, a tone burst or beep is produced. The beep prompts the user to rotate the antenna by another small increment. Once the continuous tone has been produced, a fine alignment procedure is initiated in which the antenna is rotated to locate boundaries of an azimuth arc through which the continuous tone is produced. Thereafter, the antenna is set so that it is approximately midway between the two boundaries of the arc.