| 摘要 |
PURPOSE:To avoid the deterioration in waveform even in case a low band is cut off on a transmission line by defining a differential signal between the signal obtained through the multiplication product modulation carried out between the transmission information data and an artificial random series and the signal obtained by delaying the signal obtained through the multiplication product modulation as a code of the transmission line. CONSTITUTION:The narrow band transmission information data given through a signal line 150 is multiplied by an artificial random series for modulation sent from a signal line 151 through a multiplier 100 and outputted to a signal line 152 in the form of spectrum diffusion signal. This diffusion signal is delayed by a delay circuit 101 by an amount equal to a bit of said random series and then supplied to a subtractor 102. The subtractor 102 obtains the difference between the spectrum diffusion signal sent from the multiplier 100 and a delay signal sent from the circuit 101 and transmits it to a transmission line. Thus it is possible to obtain a spectrum diffusion signal containing a reduced low frequency component and therefore to obtain a signal of transmission line that receives no deterioration in waveform even in case a low band is cut off on a transmission line, etc. |
