Echo cancelling system and echo cancelling method

An echo cancelling system, comprising:

• a data transmitter circuit configured to receive a first transmitted signal;
• and
• an echo canceller circuit comprising:
• a first filter configured to generate a first filtering signal according to the first transmitted signal, wherein a combination of the first filtering signal and a random sequence signal forms a first digital signal;
• a second filter configured to generate a second filtering signal according to the first transmitted signal;
• and
• a digital-to-analog converter configured to generate an echo cancelling signal based on the first transmitted signal and a shaping signal corresponding to the first digital signal and the second filtering signal,
• wherein the data transmitter circuit is further configured to generate an output signal according to a received signal and the echo cancelling signal.

An echo cancelling method, comprising:

• receiving a first transmitted signal by a data transmitter circuit, wherein the first transmitted signal corresponds to a first sampling rate;
• generating a second transmitted signal according to the first transmitted signal by an echo cancelling circuit, wherein the second transmitted signal corresponds to a second sampling rate, and the second sampling rate is higher than the first sampling rate;
• generating an echo cancelling signal according to the second transmitted signal by the echo cancelling circuit;
• and
• generating an output signal according to a received signal and the echo cancelling signal by the data transmitter circuit,
• wherein the received signal is different from the first transmitted signal.