Method and arrangement for signal loop test

US7069165B2 · kind B2 · utility

Assignee

• Telefonaktiebolaget LM Ericsson (Publ) · SE

Inventors

• Jonas Rosenberg · Bromma, SE
• Fredrik Lindqvist · Järfälla, SE
• Adam Wiå · Linköping, SE
• Antoni Fertner · Stockholm, SE
• Axel Jensen · Fredensborg, DK
• Per Ola Börjesson · Fontanafredda, IT
• Per Ödling · Ayacucho, PE

Key dates

• Filing date: May 7, 2004
• Grant date: Jun 27, 2006
• Expiry date: Sep 7, 2024

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04M3/306
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

The invention refers to single-ended test of a loop with the aid of a transceiver, wherein an input impedance (Zin(ƒ)) of the loop is generated. The transceiver has a digital part, a codec and an analog part and is connected to the loop. With the aid of a transmitted and a reflected broadband signal (vin, vout) an echo transfer function Hecho(ƒ)=V(f)out/Vin(f) is generated, which also can be expressed asHere Zh0(ƒ), Zhyb(ƒ) and H∞(ƒ) are model values for the transceiver. In a calibration process a test transceiver, with the same type of hardware as the transceiver, is connected to known impedances, replacing the loop. Hecho(ƒ)=V(f)out/Vin(f) is generated for the known impedances and the model values are generated and are stored in a memory in the transceiver. The stored model values are then used when the input impedance (Zin(ƒ)) for the loop is generated after a measurement of the broadband signal (Vin, vout) is performed.