Patent ID: 7542562

Claim:
Method for automatically matching the levels of the signals exchanged between a first apparatus and a second apparatus which communicates with the said first apparatus via a transmission line, characterized in that it comprises the following steps: the digital which comes from the transmission line and is received by the first apparatus is digitized, on the basis of the digital data representing the signals exchanged with the transmission line, an estimate is made of the transfer function equal to the ratio of the signal received by the first apparatus to the signal transmitted by the first apparatus, the estimate of the transfer function is defined in the following way: OUT ⁢ ⁢ 2 IN ⁢ ⁢ 1 = K ⁡ ( Z L ) + ɛ where K ⁢ ( Z ⁢ L ) = ⁢ Z ⁢ L ⁢ 2 · ( ⁢ Z ⁢ L ⁢ + ⁢ 2 · ⁢ R ⁢ 1 ) and Z L represents the impedance of the transmission line, while R 1 represents the source impedance of the transmission line, the following are calculated: for the transmitter signal, the first gain G 1 G ⁢ ⁢ 1 ⁢ ( Z L ) = 1 1 - 2 · K ⁡ ( Z L ) and for the received signal, the second gain G 2 G ⁢ ⁢ 2 ⁢ ( Z L ) = 1 1 - 2 · K ⁡ ( Z L ) . each of the exchanged signals is respectively multiplied by a suitable gain determined on the basis of the estimated value of the said transfer function.