Noise Identification in Adsl Modems

Crosstalk from adjacent telephone subscriber loops is a primary impairment for digital subscriber line (DSL) service. This paper proposes a novel solution to identify various crosstalk sources in the current ADSL system. The algorithm takes the base power spectrum density (PSD) as a prior for each type of crosstalk, and compute a MSE solution based on the overall noise PSD. However, in a practical situation, the model mismatch and other unknown interference may greatly degrade the accuracy of the result. The major contribution of the paper is to provide a robust solution for the crosstalk identification in the presence of radio frequency interference (RFI) and other unknown interference. Simulation result is provided at the end.