Sequence Time Domain Reflectometry for Transmission Line Analysis

Jacklyn Reis, Agostinho Castro, João Crisostomo Weyl Albuquerque Costa, Jaume Riu, Klas Ericson

DOI: 10.14209/sbrt.2007.31286

Evento: XXV Simpósio Brasileiro de Telecomunicações (SBrT2007)

Keywords: Loop qualification digital subscriber line sequence time domain reflectometry spread spectrum

Abstract

This paper describes Sequence Time Domain Reflectometry (STDR), which utilizes concepts from direct sequence spread spectrum communications, as a technique for detecting impedance mismatches in telephone lines (twisted pair). The aim of this paper is to present methodologies for characterizing a subscriber loop, which is used for Digital Subscriber Line (DSL) technology, based on STDR tests. Those tests enable the TDR functionality to be incorporated into a DSL transceiver integrated circuit eliminating the need for costly test equipment. In addition to the cost savings, the characteristics of the STDR offer improved spectral compatibility, interference immunity and fault resolvability.

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