METHOD OF PROCESSING MULTI-LEVEL SIGNALS FOR SIMPLE CLOCK RECOVERY

摘要

A method and a circuit for simple clock recovery from multi-level at high transmission rates. The circuit is compatible with standard PLL- type clock recovery techniques for NRZ and generalized two-level signalling. The timing information is extracted from a single threshold crossing, irrespective of the number of levels (M) of the signal. This was verified to provide sufficient spectral information for the proper operation of a clock recovery PLL. The threshold may be programmed for various line codes.