Transmission characteristics of cascade relays using a single frequency in DTTB

Abstract

At a TV relay station in SFN, transmission characteristic is more or less degraded with the coupling from transmitter to receiver. The degradation is gradually accumulated through cascade relays and in case of large coupling, transmission characteristic results in failure. By controlling the phase of a coupling signal to compensate the distorted spectrum in each station, the degradation can be suppressed to an allowable amount under a certain condition.