Cable System Response Analysis

(Matlab Models, Reports and Hardware)



The design of 100BaseTX, 1000BaseT, 10GBaseT and other copper based physical layer devices are highly dependent on the characteristics of the cable plant. Hence accurate measurements of real cable plant can be used during the design process to lower device costs, improve performance, and reduce design time.

However, there are a wide variety of potential cable plant configurations, manufactures, and specifications. As a result, making a thorough set of cable measurements is a lengthy and expensive process.

Obsidian Technology provides a solution to the problem of cable plant characterization with an extensive test report of the performance of a variety of typical and worst case configurations in paper and ready to use Matlab/SimulinkTM formatted forms.


Cable Plant Configurations

Cable plan configurations typically include the following:

  • Single continuous cables at five different lengths.rack11
  • As above with induced worst case impedance matching.
  • 4 different cable manufactures and/or cable specs.
  • Typical plant configurations with combinations of cable runs, wall connectors, and punch down arrangements.
  • As above with induced worst case impedance matching.
  • Effects of including down rev fixtures.
  • Effects of cable knots and exposed insulation.


Each cable configuration will be characterized using an impulse generator and a high sampling oscilloscope as well as the usual Network Analyzer measurements. This provides a direct measurement of impulse response for comparison. Custom termination boards provide necessary 4 pair impedance matching (and controlled mismatch) and interface Balun. Also, the effect of various connector types. Cable plant configuration measurements will include the following:

  • Cable attenuation.
  • Inter pair Near End Cross Talk (NEXT).
  • Inter pair Far End Cross Talk (FEXT).
  • Echo response for cable plant combinations and for simplified echo characterization cable setups with induced echo scenarios to permit general echo characterization.
  • Simple resistive hybrid loss.

Report Content


  • CD-ROM with a complete set of raw data and processed data in Matlab form and a soft copy of the complete report..
  • Copies of scripts used to process raw data.
  • Details of experimental setups with serialized equipment lists and plant manufacture names etc.
  • Photographs of key measurement setups.
  • Presentation of processed data showing worst case characteristics verses cable plant variables.
  • A set of composite worst case time domain Matlab cable models.

Service Features

  • On site presentation of the data.
  • One year data updates included.
  • Optional additional custom measurements.
  • Optional purchase of cable plant simulation rack.
  • Available custom C models per your specification.