Multipoint connected communication system having function of retraining modems provided therein and method of retraining the modems

摘要: A communication system in which a plurality of multipoint connected satellite stations are via down line and an up to master station. Each the monitors presence or absence occurrence abnormality line, judges whether is present not and, where present, informs station nature line. In turn, alarm indicating from each stations, detected detected, reads past record information concerning detection concerned on retraining execution time, then normal normal, sends training signal again retrain MODEM corresponding concerned. Accordingly, it possible quickly restore demodulation processing by respective status after recovery trouble