| 摘要 |
PURPOSE:To execute transmission by small power even if case of a distribution line whose signal transmission characteristic is inferior, and also constituting it so that it is not effected by noises, etc., by applying a spread spectrum communicating system, when information is transmitted by using a commercial distribution line as a signal transmission line. CONSTITUTION:In case signal transmission between a master station R installed at an electric place and slave stations S1-S3 provided on positions separated from the master station is executed through a commercial distribution line 20, the master station R and respective slave stations S1-S3 are connected to the distribution line through a high-pass filter F, a coupling device H and transformers T1, T2, respectively, and the signal transmission is executed by a spread spectrum communicating system. In this spread spectrum communicating system, a signal input of F1 is diffused to a frequency between f1-f1' based on the regularity determined in advance by a prescribed time and sent out to the line, and in this receiving side, its reverse means (reverse diffusion) is executed so that the signal is concentrated on F1, and the signal transmission is executed. |
