CARRIER RECOVERY DEVICE FOR QAM RECEIVER AND METHOD FOR RECOVERING CARRIER USING THE SAME

摘要

PURPOSE: A carrier recovery device for QAM receiver and a method for recovering a carrier using the same are provided to detect an accurate phase error value and obtain a carrier with a fast convergence speed. CONSTITUTION: A carrier recovery device for QAM receiver and a method for recovering a carrier using the same comprise a main decision portion(30), a sub-decision portion(31), a decided data selection portion(32), a phase error detection portion(33), a layer determination portion(38), a pass/maintenance portion(34), a loop filter(35), a carrier obtainment detection portion(37) and a voltage control oscillation portion(36). The main decision portion receives I, Q data through a channel and outputs decision data. The sub-decision portion outputs data existed on a first layer as decision data. The decided data selection portion output a decided data value. The phase error detection portion detects errors of the decided data. The layer determination portion determines whether the received I, Q data belongs to the first layer or not. The pass/maintenance portion penetrates a current phase error or maintains a previous phase error. The loop filter removes a noise of an output signal from the pass/maintenance portion and outputs a pure phase error. The carrier obtainment detection portion detects whether an output signal of the loop filter obtains a carrier and transfers a detection signal to the decided data selection portion. The voltage control oscillation portion recovers a carrier for modulating a transmission signal.