A DIGITAL TV SIGNAL USING SPECIAL NTSC RECEIVER TO DETECT WHEN CO-CHANNEL INTERFERING NTSC SIGNAL FROM AUXILIARY ANALOG TV RECEIVERS FOR DETECTING NTSC INTERFERENCE IN DIGITAL TV RECEIVERS

摘要

During a period of transition from broadcasting analog TV signals to broadcasting digital TV signals, digital TV reception is susceptible to disruption owing to co-channel interference by analog TV signals. During this same transition period usually a digital TV receiver will incorporate an auxiliary analog TV receiver. This auxiliary analog TV receiver is advantageously used during digital TV signal reception for determining the amount of co-channel interference by analog TV signals, so that comb filtering can be selectively applied to symbol coding recovered from the digital TV signal, for suppressing artifacts of co-channel interfering analog TV signal when they are large enough to have substantial adverse on symbol decoding. The amount of co-channel interference is estimated from synchronously detected analog TV signal.