RELAY BROADCASTING DEVICE,申请号JP19980281714-传众专利搜索

RELAY BROADCASTING DEVICE

申请公布号：JP2000115048(A)

申请号：JP19980281714

申请日期：1998.10.02

申请公布日期：2000.04.21

申请人：

JAPAN RADIO CO LTD

发明人：MARUYAMA TAKASHI;KARASAWA KAZUSHIGE

分类号：H04J11/00;H04B7/15;(IPC1-7):H04B7/15

主分类号：H04J11/00

摘要：PROBLEM TO BE SOLVED: To increase the cancel effect on a wave traveling round to a receiving antenna from a transmitting antenna as to the relay broadcasting device which amplifies a broadcast wave received by the receiving antenna and sends a broadcast wave of the same frequency from the transmitting antenna like a ground digital broadcasting system using a single frequency network. SOLUTION: To the input side of a frequency converting circuit (mixer) 36 in a transmitter 10B, the input/output side of a series circuit of a cancel circuit 46 which can adjust a delay time, an amplitude, and a phase respectively and a band-pass filter which is provided in a receiver 6B and has the same transfer characteristics with a band-pass filter 32 on a main path is connected. Consequently, a detour closed loop FL and a cancel closed loop CLB have the same transfer characteristics and the cancel effect on the detour wave R1 can be increased.