Patent ID: 6381236
Filing Date: 2002-04-30
Classification: H04L

Abstract:
A bi-directional digital transmission system for transmitting digital transmission signals having a frame configuration modulated by an orthogonal frequency division multiplex modulation scheme, said bi-directional digital transmission system comprising:a first transmission station including a first sending unit, a first receiving unit, a first switchover unit connected to an output of said first sending unit and an input of said first receiving unit, selection of either the output of said first sending unit or the input of said first receiving unit being controlled by said first sending unit, and a first sending/receiving path connected to the selected output of said first switchover unit; and a second transmission station including a second sending unit, a second receiving unit, a second switchover unit connected to an output of said second sending unit and an input of said second receiving unit, selection of either the output of said second sending unit or the input of said second receiving unit being controlled by said second receiving unit, and a second sending/receiving path connected to the selected output of said second switchover unit, wherein in said first transmission station said first sending unit converts first continuous data to an up-direction intermittent transmission signal and sends said up-direction intermittent transmission signal from said first sending/receiving path via said first switchover unit during a first sending period, and in said second transmission station said second receiving unit restores the original first continuous data from said up-direction intermittent transmission signal received by said second sending/receiving path and supplied via said second switchover unit, and in said second transmission station said second sending unit converts second continuous data to a down-direction intermittent transmission signal and sends said down-direction intermittent transmission signal from said second sending/receiving path via said second switchover unit during a second sending period, and in said first transmission station said first receiving unit restores the original continuous data from the down-direction intermittent transmission signal received by said first sending/receiving path and supplied via said first switchover unit, said first and second sending periods appear alternately and repetitively.