An interpolation filter based on spline functions for non-synchronized timing recovery

In a fully-digital receiver, the sampling of the received signal is not synchronized to the incoming data symbols. In this type of receiver, timing recovery must be performed using interpolation. In this paper, we propose an infinite impulse response (IIR) interpolation filter based on a spline function. This interpolation filter provides a significantly lower Signal-to-Noise (SNR) degradation compared to other conventional filters. This filter is especially suitable for receivers without equalization or during the initialization mode, when equalization has not been yet established.