Chebyshev interpolation for DMT modems

Sampling clock synchronization in discrete multi tone systems, such as digital subscriber line modems can be done with a phase locked loop. This requires expensive analog hardware, such as a voltage controlled oscillator. However, it is possible to use a cheaper free-running oscillator and tackle the problem in the digital domain. Using resampling or interpolation, the timing correction becomes transparent for subsequent equalizers. This article describes a novel resampling technique using Chebyshev polynomials.