| 摘要 |
PURPOSE:To extract a communication signal by eliminating steady noise with high accuracy in the case of reception processing by extracting the communication signal for a prescribed frequency band sent through a distribution line. CONSTITUTION:This receiver is provided with a reception input section such as a transformer or the like detecting a voltage or a current of a distribution line, an input filter section 1 extracting only a component for a prescribed frequency band from a detection signal S1 of the input section, a harmonic extract filter section 2 discriminating and extracting a frequency component of each harmonic being an elimination object of a system power supply from an output signal S2 of the filter section 1, a steady noise detection output section 3 oscillating an approximation signal of each harmonic with loop control of each output signal from the filter section 2 before the transmission of the communication signal and reconstituting the steady noise signal S9 resulting from synthesizing approximate signals of each harmonic at the transmission of the communication signal, and a signal extract section 4 extracting a communication signal S10 by subtracting the steady noise signal S9 from the output signal S2 of the filter section 1 at the transmission of the communication signal. |
