Patent ID: 6999504

Claim:
A telecommunication system having reduced crosstalk comprising: a modem disposed at a customer premises; a local loop terminating at the customer premises and connected to the modem, the local loop for carrying modem communications; a first circuit disposed to sense the signal received on the local loop; a second circuit configured to obtain a common mode signal from the local loop; and a processor circuit disposed within the modem, the processor configured to reduce crosstalk on the local loop through computations based upon both the signal received on the local loop and the common mode signal, wherein the processor circuit is configured to process a signal that takes in the time domain, after digitization, the following forms: p [ n ]=( f{circle around (x)}u )[ n ]+( l{circle around (x)}e )[ n ]+ w [ n ], common mode signal and r [ n ]=( h{circle around (x)}e )[ n ]+( g{circle around (x)}u )[ n ]+ v [ n ], differential mode signal, where w[n] and v[n] are independent white noise quantities, r[n] is the signal received on the local loop, p[n] is the common mode signal, h[n] is an impulse response of the first local loop, l[n] is a cross-coupling measure between the local loop and the common mode, u[n] is a signal carried on a disturber line, f[n] is a cross-coupling measure between the disturber line and the common mode signal, e[n] is the signal transmitted from a remote transmitter on the local loop, g[n] is a cross-coupling measure between the disturber line and the local loop, and wherein the {circle around (x)} symbol represents a convolution operation.