Telephone communication system and method over local area network wiring

摘要

A device for enabling a local area network wiring structure to simultaneously carry digital data and analog telephone signals on the same transmission medium. It is particularly applicable to a network in star topology, in which remote data units (e.g. personal computers) are each connected to a hub through a cable comprising at least two pairs of conductors, providing a data communication path in each direction. Modules at each end of the cable provide a phantom path for telephony (voice band) signals between a telephone near the data set and a PBX, through both conductor pairs in a phantom circuit arrangement. All such communication paths function simultaneously and without mutual interference. The modules comprise simple and inexpensive passive circuit components.

主权项

1. A device for a local area network (LAN), the LAN including a LAN cable having at least four wire pairs to carry a plurality of data signals, and the device comprising:
a first transformer having a primary winding and a secondary winding, the first transformer being operative to pass a first data signal; a second transformer having a primary winding and a secondary winding, the second transformer being operative to pass a second data signal; a third transformer having a primary winding and a secondary winding, the third transformer being operative to pass a third data signal; a fourth transformer having a primary winding and a secondary winding, the fourth transformer being operative to pass a fourth data signal, and the primary winding of each one of the transformers being communicatively couplable to a respective one of the four wire pairs, the secondary winding of each one of the transformers being arranged within the device for transferring a respective one of the data signals to or from the associated primary winding, and wherein a first center-tap connection of the primary winding of any one of the transformers and a second center-tap connection of the primary winding of any other one of the transformers form a pair of center-tap connections for receiving a phantom signal from a first phantom channel defined over the two pairs of the four wire pairs that correspond by coupling relation to the pair of center-tap connections; and a single enclosure housing the first, second, third and fourth transformers, and the device being configured to provide the phantom signal to a power consuming device.