Digital communication receivers P9

Timing Adjustment by Interpolation In this chapter we focus on digital interpolation and interpolator control. In Section 9.1 we discuss approximations to the ideal interpolator. We first consider FIR filters which approximate the ideal interpolator in the mean square sense. A particularly appealing solution for high rate applications will be obtained if the dependency of each filter tap coefficient on the fractional delay is approximated by a polynomial in the fractional delay. It is shown that with low-order polynomials excellent approximations are possible. In Section 9.2 we focus on how to determine the basepoint m, and fractional delay Pi, considering...