xDSL Network Upgrade Employing FPGAs

This paper proposes an upgrade scenario for xDSL networks to provide broadband access for extended link lengths while demonstrating network grooming by means of more than one subscriber using a single network connection concurrently. This is achieved by applying direct spread code division multiple access (DS-CDMA) in a fiber-to-the-cabinet (FTTC) topology by means of a field programmable gate array (FPGA), used to demonstrate simultaneous user transmission and system-on-chip (SoC) network element generation. Experimental results have displayed efficiency in ADSL link rates of 66% and 41% for back-to-back and 12 km-reach fiber links respectively.