A ROBUST AND FAST-LOCKING ALL-DIGITAL CARRIER RECOVERY LOOP FOR QAM SIGNALS

摘要

The paper presents the design and the implementation of an all-digital carrier recovery loop for QAM-modulated signals.Original features concerning the programmability of the loop,its fast-locking properties in acquisition and restart procedures as well as its wide acquisition range are discussed.Emphasis is also put on its performance in terms of robustness versus noise and intersymbol interference and protection against potential frequency false-locks.Experimental results are reported for a 16-QAM system.