Patent ID: 6621527
Filing Date: 2003-09-16
Classification: H04L,H04N

Abstract:
A radio receiver for receiving amplitude modulation of a suppressed carrier descriptive of a digital TV signal, said digital TV signal having a plurality of successive data fields each including a respective data field synchronization code at the beginning thereof, said digital TV signal including symbol codes of various amplitudes in the rest of each of said successive data fields, said amplitude modulation accompanied by a pilot carrier of the same frequency as said suppressed carrier and of an amplitude relatively small compared to said amplitude modulation during the transmission of said data field synchronization code, said radio receiver comprising:a tuner supplying an amplitude modulation of an analog intermediate-frequency suppressed carrier amplitude modulated in accordance with said digital TV signal, said amplitude modulation having an envelope exhibiting amplitude variations in response to said symbol codes, and owing to the accompanying pilot carrier said amplitude modulation having an envelope exhibiting amplitude variations in response to said data field synchronization codes; a demodulator demodulating said amplitude modulation of said amplitude modulated analog intermediate-frequency suppressed carrier to supply a baseband response including reproduced data field synchronization codes in response to said amplitude variations in response to said data field synchronization codes; and a field match filter receiving as its input signal said baseband response and generating a respective pulsed match filter response each time a prescribed portion of said reproduced data field synchronization codes occurs.