Adjustment of transmit power based on an estimated electrical length of a loop

摘要

To adjust transmit power of a DSL modem, an estimated electrical length of a loop is first determined when a 1^st DSL modem at a 1^st location transmits a plurality of signals to a 2^nd DSL modem at a 2^nd location. Each of the signals transmitted by the 1^st DSL modem have a known frequency and are transmitted at a known power level. Upon receiving the signals, the 2^nd DSL modem determines the received power level for each of the signals. The 2^nd DSL modem then estimates an electrical length of a loop between the 1^st and 2^nd DSL modems for each of the signals received. The 2^nd DSL modem then processes a plurality of estimated electrical lengths in accordance with a function to produce a determined electrical length. Having determined the electrical length, the 2^nd DSL modem adjusts its transmit power accordingly.