Facsimile machine having a phase/amplitude fluctuation detector

摘要

A facsimile machine includes a phase/amplitude fluctuation detector for quantitatively detecting fluctuation of the phase and amplitude of data received at a modem and a reception speed determiner for determining if the reception is to be continued or not and at which communication speed the data is to be received if reception is to continue, based on the fluctuation values detected at the phase/amplitude fluctuation detection means. The facsimile machine quantitatively detects the fluctuation values of the phase and the amplitude of the signal being received. When the fluctuation values exceed a designated range, even if the bit-pattern of the received data is normal, the facsimile machine starts receiving video information via a one-step reduced communication speed and therefore can accurately receive the video information even if the telephone circuit condition is not good.