Signal processing method in dsl system, apparatus, and system

A network-side device, comprising:

• n signal transceiver units configured to send a downstream signal to n customer premises equipments through n subscriber lines;
• a downstream signal compensation unit configured to:
• when determining there is no to-be-sent downstream signal on m (n>m≧1) subscriber lines in the n subscriber lines, superimpose a signal X=(x1, x2, . . . , xm) on the m subscriber lines, so that a signal output on the m subscriber lines after precoding processing is 0, wherein xm indicates a signal component loaded on the mth subscriber line in the m subscriber lines;
• a precoder configured to perform precoding processing on the downstream signal on the n subscriber lines;
• and
• a signal transceiver unit configured to send the downstream signal that has undergone the precoding processing on another line except the m subscriber lines in the n subscriber lines.

A digital subscriber line (DSL) system, comprising:

• a network-side device, n customer premises equipments, and n subscriber lines connecting the network-side device to the n customer premises equipments, wherein the n subscriber lines are twisted pairs;
• and
• the network-side device is configured to:
• when determining there is no to-be-sent downstream signal on m (n>m≧1) subscriber lines in the n subscriber lines, superimpose a signal X=(x1, x2, . . . , xm) on the m subscriber lines, so that a signal output on them subscriber lines after precoding processing is 0, wherein xm indicates a signal component loaded on the mth subscriber line in the m subscriber lines,
• perform precoding processing on the downstream signal X=(x1, x2, . . . , xm) on the m subscriber lines and a downstream signal on another line, wherein the other line is (n−m) subscriber lines except the m subscriber lines in the n subscriber lines,
• not perform front-end processing on the signal on the m subscriber lines,
• perform front-end processing on the downstream signal that has undergone the precoding processing on the another line, and
• send the downstream signal to a customer premises equipment through the another subscriber line.

A computer readable storage medium, configured to store computer program code that is used to execute a signal processing method in a digital subscriber line (DSL) system, wherein the DSL system comprises a network-side device and n subscriber lines, and wherein the network-side device sends a downstream signal to n customer premises equipments through the n subscriber lines, the signal processing method comprising:

• determining there is no to-be-sent downstream signal on m (n>m≧1) subscriber lines in the n subscriber lines;
• superimposing a signal X=(x1, x2, . . . , xm) on the m subscriber lines, so that a signal output on the m subscriber lines after precoding processing is 0, wherein xm indicates a signal component loaded on the mth subscriber line in the m subscriber lines;
• performing precoding processing on the downstream signal on the n subscriber lines;
• and
• sending the downstream signal that has undergone the precoding processing on another line except the m subscriber lines in the n subscriber lines.