Single ended line probing in DSL system

A system for estimating the length of a transmission medium, comprising:

• a transformer coupled to the transmission medium, for coupling signals to the transmission medium;
• a transmitter operatively coupled to the transformer and configured to transmit a probe signal over transmission medium;
• a receiver operatively coupled to the transformer and configured to receive a reflected version of the probe signal;
• and
• a processor operatively coupled to the receiver and configured to estimate the length of the transmission medium by determining a transmission medium impedance based on the transmitted probe signal and the reflected version of the probe signal, comparing the transmission medium impedance to a plurality of predetermined impedances, wherein each predetermined impedance is associated with a known transmission medium length, and estimating the length of the transmission medium based on the comparison.

A computer-readable medium having stored thereon instructions which, when executed by a processor, cause the processor to perform the steps of:

• measuring a reflected version of a transmitted probe signal received from a transmission medium;
• determining a transmission medium impedance based on the transmitted probe signal and the reflected version of the probe signal;
• comparing the transmission medium impedance to a plurality of predetermined impedances, each predetermined impedance associated with a known transmission medium length;
• and
• estimating the length of the transmission medium based on the comparison.

A system for estimating the length of a transmission medium, comprising:

• means for measuring a reflected version of a transmitted probe signal received from a transmission medium;
• means for determining a transmission medium impedance from the transmitted probe signal and the reflected version of the probe signal;
• means for comparing the transmission medium impedance to a plurality of predetermined impedances, each predetermined impedance associated with a known transmission medium length;
• and
• means for estimating the length of the transmission medium based on the comparison.

A method of estimating the length of a transmission medium in a Digital Subscriber Line (DSL) system, comprising:

• transmitting a probe signal over the transmission medium by way of a transformer coupled to the transmission medium;
• measuring a reflected version of the probe signal received from the transmission medium;
• determining a transfer function characterizing the transmission medium and the transformer based on the transmitted probe signal and the reflected version of the probe signal;
• and
• estimating the length of the transmission medium based on the transfer function.

A Digital Subscriber Line (DSL) modem for estimating the length of a transmission medium, comprising:

• a transformer coupled to the transmission medium, for coupling signals to the transmission medium;
• a transmitter operatively coupled to the transformer and configured to transmit a probe signal over transmission medium;
• a receiver operatively coupled to the transformer and configured to receive a reflected version of the probe signal;
• and
• a processor operatively coupled to the receiver and configured to estimate the length of the transmission medium by determining a transfer function characterizing the transmission medium and the transformer based on the transmitted probe signal and the reflected version of the probe signal;
• and estimating the length of the transmission medium based on the transfer function.

A computer-readable medium having stored thereon instructions which, when executed by a processor, cause the processor to perform the steps of:

• transmitting a probe signal over the transmission medium by way of a transformer coupled to the transmission medium;
• measuring a reflected version of the probe signal received from the transmission medium;
• determining a transfer function characterizing the transmission medium and the transformer based on the transmitted probe signal and the reflected version of the probe signal;
• and
• estimating the length of the transmission medium based on the transfer function.