Title :
A line terminating LSI using echo cancelling method for ISDN subscriber loop transition
Author :
Fukuda, Misao ; Tsuda, Toshitaka ; Gambe, Hirohisa ; Hino, Youzi
Author_Institution :
Fujitsu Labs. Ltd., Kawasaki, Japan
fDate :
4/1/1988 12:00:00 AM
Abstract :
A 144-kb/s digital subscriber loop (DSL) transmission system based on hybrid transmission with an echo cancelling method is described. It incorporates advanced LSI technology to obtain compactness, low cost, and high reliability. An echo canceller (EC) LSI has been developed using CMOS technology. Combined with the multiplexing processor (MXP) LSI, the EC LSI provides basic DSL equipment functions. A specially arranged frame format with a newly developed digital phase-locked loop (DPLL) circuit for stable timing extraction, an automatic balancing network, and a two-stage echo canceller characterize the system. Using this line termination circuit, the DSL equipment showed a reach of over 6 km when used with 0.5 mm diameter cable for 160-kb/s bidirectional digital transmission
Keywords :
CMOS integrated circuits; ISDN; echo suppression; large scale integration; phase-locked loops; subscriber loops; 0.5 mm; 144 kbit/s; 160 kbit/s; 6 km; CMOS technology; ISDN subscriber loop transition; automatic balancing network; bidirectional digital transmission; digital phase-locked loop; digital subscriber loop; echo cancelling; frame format; hybrid transmission; line terminating LSI; multiplexing processor; stable timing extraction; CMOS technology; Circuits; Costs; DSL; Echo cancellers; ISDN; Large scale integration; Multiplexing equipment; Phase locked loops; Timing;
Journal_Title :
Selected Areas in Communications, IEEE Journal on
