Junzo Murakami

A Novel Automatic Ghost Canceller

Ghost is one of the most serious problems in TV reception. Ghost reduction is highly desirable, and some automatic deghosting systems have been reported [1] ,[2] [3], [4]. All the systems utilize transversal filters. The approach with a transversal filter may be the best way.

A Fully Automatic Ghost Canceller

Ghost may be one of the largest remnaining causes of picture degradations as TV broadcast and receivers quality increases rapidly. Even the best antennas are not always adequate to remove ghosts. Most of the existing systems are not practical because they must be readjusted for each channel and different meteorogical conditions.

A Digitalized Automatic Ghost Cancerller

Among various approaches for realizing a practical ghost canceller, the one based on an adaptive transversal filter has recently been studied most enthusiastically.(1) ~(3) The inherent merit of this approach lies in the fact that it can cancel diffused multiple ghosts, generated by complex transmission path irregularities. This feature can not be attained by a single-delay-line ghost canceller.

A Digital Time Domain Equalizer for Teletext

Some trials to reduce TV ghosts have been reported, utilizing transversal filters. (114) They are effective for video ghost reduction as well as for Teletext equalizing.

A TV Ghost Canceller Using a CCD Transversal Filter

A system study has been conducted on a transversal filter ghost canceller to achieve system optimization, and an LSI CCD transversal filter for use in the ghost canceller was developed. Furthermore, a practical model of the ghost canceller was constructed on a trial basis. The results of field tests made on the test equipment showed that this system could improve TV picture quality by more than one grade in a five grade subjective evaluation and that the ghost canceller would be useful in practical applications.