LINE QUALITY DETECTION DEVICE, LINE QUALITY DETECTING METHOD AND LINE SWITCHING DEVICE USING THE SAME, AND LINE SWITCHING METHOD

摘要

<P>PROBLEM TO BE SOLVED: To obtain a line quality detection device of a simple configuration which is compatible between a line detection speed and line detection accuracy which have mutually a tradeoff relation by using only a syndrome pulse. Ž<P>SOLUTION: The line quality detection device includes: a first line quality detecting means 1 for monitoring the occurrence frequency of a syndrome error pulse generated in response to the detection of a bit error of a transmission signal in a first period and detecting a line quality state; a second line quality detecting means 2 for monitoring the occurrence frequency of the syndrome error pulse in a second period shorter than the first period to detect a line quality state; and an alarm signal generating means 3 for generating an alarm signal when at least one of detection results of the first and second line quality detecting means indicates line quality deterioration. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž