Communications system

PROBLEM TO BE SOLVED: To organize, by parallel establishment, a high-frequency and high-speed communication network with a frequency band being higher than the frequency of communication in the transmission lines of the communication through the use of the existing or newly-established transmission lines of a contact communication line for maintenance, etc., to be used for a purpose such as the introduction and routine inspection, etc., of a private telephone line, a private broadcast line, or private equipment. SOLUTION: A communication system includes: a high-frequency communication master station 4 which is connected by high frequency to the main transmission line of the communication system, where one-to-one communication is performed with the transmission lines having the main transmission line 3M and the plurality of parallel branch transmission lines 3B, via an additionally-established main transmission line 3AM; and a plurality of high frequency communication slave stations 5 which are connected by high frequency to the respective branch transmission lines via additionally-established branch transmission lines AB. The high-frequency communication of M:N (M is a natural number not less than one, N is a natural number not less than 2) is performed between the high frequency communication master station and the respective high-frequency communication slave stations by defining the additionally-established main transmission line, the branch transmission lines, and the additionally-established branch transmission lines as transmission media. COPYRIGHT: (C)2008,JPO&INPIT