SYSTEM AND DEVICE FOR, AND METHOD OF, DETECTING, CHARACTERIZING, AND MITIGATING DETERMINISTIC DISTORTION IN A COMMUNICATIONS NETWORK

摘要

PURPOSE: A system is provided to detect, characterize, and mitigate deterministic distortion in a communication system. CONSTITUTION: An exemplary communication system includes a digital adaptor for sending octets on to a backbone of a PSTN, which then sends, and potentially distorts the octets, received by a line interface. The line interface converts the octets to baseband signals received by an analog adaptor. Several mechanisms and methods are described in which the analog and digital adaptor cooperate to detect the presence of distortion, in particular, robbed bit signaling, on the communication system. The characterization may then be used to mitigate the effects of the distortion. Several receive constellations are provided, each constructed in view of the transmit constellation and in view of the manner in which the deterministic distortion will distort signals transmitted over the system. The receive constellations differ from the transmit constellation. The analog adaptor uses an appropriate receive constellation based on the type of distortion expected at a given interval. The digital adaptor may similarly include several constellations in view of the same considerations.