Patent ID: 7069165

Claim:
A Method in single-ended test of a signal line, the method comprising the steps of: Selecting a test transceiver; Connecting impedances each of a predetermined value to a line connection of the test transceiver; generating, in a calibration process, calibration values for the test transceiver with the aid of said impedances and test signals (vt in , vt out ), generating for the test transceiver frequency dependent echo transfer functions (H echo (ƒ)) utilizing at least three impedances; generating test transceiver model values (Z h0 (ƒ), Z hyb (ƒ), H ∞ (ƒ)) with the aid of said echo transfer functions (H echo (ƒ)) and the corresponding impedance values, said model values including an echo transfer function (H ∞ (ƒ)) for the test transceiver with open line connection, a test transceiver impedance value (Z hyb (ƒ)) as seen from the line side and a product (Z h0 (ƒ)) of said transceiver impedance value (Z hyb (ƒ)) and an echo transfer function (H 0 (f)) for the test transceiver with shortcut line connection; selecting a transceiver for communication purposes of the same type of hardware as said test transceiver; and storing the transceiver model values (Z h0 (ƒ), Z hyb (ƒ), H ∞ (ƒ)) in said transceiver for communication purposes.