Patent · US Expired

Non-invasive digital cable test system

US6233274A · kind A · utility

37Cited by
13References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1999
Grant dateMay 15, 2001
Priority date
Expiry dateSep 30, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L43/00
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Method and apparatus for non-invasive testing of digital communications systems. Amplitude measurements are made for multiple frequencies of a multi-frequency communication system, converted to the time domain. An adaptive filter output is matched to the time domain representation to characterize the channel. Impedance mismatches may be precisely located using this technique. An error signal representing a difference between a signal transmitted through the channel and a received signal is estimated and analyzed. The error signal is separated into components corresponding to contributions by wide band noise, residual phase modulation, and residual amplitude modulation. Identification and removal of narrow-band interferers may occur prior to this separation. Bit error rate and system margin computations employ a Monte Carlo simulation of the various error sources. This provides a well refined estimate of bit error rate and system margin.

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