Prefilter Bandwidth Effects in Data Symbol Phase Synchronizers of Mixed Loop

摘要

This work studies the effects of the prefilter bandwidth in the symbol synchronizers of mixed loop. The prefilter bandwidth B is switched between three values, first B1=Ȃ2; (infinite), after B2=2.tx and next B3=1.tx, where tx is the bit rate. The synchronizer of mixed loop is based on a tuned filter followed of a PLL (Phase Lock Loop). We consider four PLL types, namely, the analog (ana), hybrid (hib), combinational (cmb), and sequential (seq). The objective is to study the prefilter bandwidth with the four synchronizers and to evaluate their output jitter UIRMS (Unit Interval Root Mean Square) versus input SNR (Signal to Noise Ratio).