There are areas where Digital Signal is hard to be reached, Area behind the Mountains, the spaces behind or Area blocked by Tall Building, or in underground areas. MASPRO DENKOH has developed the GAP FILLER SYSTEM for Terrestrial Digital Broadcasting so as to enable broadcast receiving in these areas. What matters are coupling loop interference and multipath interference. The loop interference is caused by the coupling from the transmitting antenna to receiving antenna. And the multipath interference is caused by the propagation phenomenon that results in a signal reaching the receiving antenna by two or more paths. Both the coupling loop and multipath may cause interference to TV pictures. MASPRO DENKOH's Transmitter for Terrestrial Digital Broadcasting enables reducing coupling-loop-interference and multipath, causing TV picture failure. MASPRO DENKOH strives to research and develop digital equipment aiming at enabling realization of the good TV pictures on environment.