Patent · US Expired

PCM upstream and downstream system for universal digital loop carrier

US6785340B1 · kind B1 · utility

5Cited by
13References
44Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 25, 2000
Grant dateAug 31, 2004
Priority date
Expiry dateMay 25, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04Q2213/13381
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A central office line unit (COLU) for a pulse code modulation (PCM) upstream and downstream system in a universal digital loop carrier (UDLC) includes a hybrid circuit for transmitting/receiving an analog signal to/from a switch. An analog-to-digital converter is provided for receiving the analog signal from the hybrid circuit and converting the analog signal to a converted digital signal. A digital transmission circuit transmits/receives a digital signal to/from a remote terminal. A quantizer is provided for evaluating and processing the converted digital signal so that only valid states of the converted digital signal are transmitted to the digital transmission circuit for transmission to the remote terminal. A receiver is used for receiving the digital signal from the digital transmission circuit and for evaluating and processing the digital signal so that only valid states of the digital signal are outputted from the receiver. A transmitter receives the digital signal from the receiver and equalizes the digital signal. And, a digital-to-analog converter converts the equalized digital signal to a converted analog signal and transmits the converted analog signal to the hybrid cir…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.