MESSAGE METERING SYSTEM HAVING MULTI-LEVEL SIGNALS AND PARTY DISCRIMINATION

摘要

.GAMMA. Disclosed is a local message metering system for metering information concerning each subscriber's use of a telephone system. Each subscriber is associated with a multi-state signal which is directly connected to the metering system to indicate subscriber usage of the telephone system. A multi-state signal for each calling subscriber is impressed on the sleeve lead within the office trunk circuits and is therefore connected through the switching exchange to the main distribution frame where all subscribers are connected. Each sleeve for a connected calling subscriber carries a unique multi-state signal associated with that subscriber. The multi-state signal for each subscriber is digitally encoded, scanned and interpreted and recorded by the metering system. The discrimination between parties on a multi-party subscriber line is performed by signals on the sleeve of different state for each party.