Line by line correction of teletext data under multipath transmission
Qingyuan Zeng, Wenbing Wang, Xuefeng Shen · IEEE Transactions on Consumer Electronics · 1992
Due to the severe interference of multipath propagation, a received teletext signal is often detected with many errors. The interference generally comes from large ghosts and conventional equalizers are unable to suppress it. A line-by-line teletext data correction technique is presented. The technique is based on two facts: (a) there is a period of time without any signal between the horizontal sync and the front end of every scanning line and (b) large ghosts have typically small delays of less than that period. Both theoretical analyses and experimental results show that the technique is effective to correct the teletext data.>