BANDWIDTH-EFFICIENT DIGITAL TRANSMISSION OVER UNSHIELDED TWISTED-PAIRWIRING

This paper describes techniques for achieving data rates up to 155 Mb/ s over unshielded twisted-pair (UTP) wiring for local area network (LA N) applications in premises distribution systems, Duplex operation at these high data rates is achieved over two pairs of UTP wiring and wit h a bandwidth utilization that is less than 30 MHz, thus avoiding pote ntial problems with radiation limits, The transmission scheme used for these LAN applications is carrierless AM/PM (CAP), which is a bandwid th-efficient two-dimensional passband encoding scheme. The paper also discusses in some detail a technique called NEXT equalization, which a llows several users to share the same cable.