Synchronization code recovery circuit and method

#This application claims the benefit of Korean Patent Application No. 2002-19967 filed on April 12, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

#1. Field of the Invention

#The present invention relates to a circuit which reliably recovers a synchronization code in an optical disc system and a method thereof.

#The above objects and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the accompanying drawings in which:

#FIG. 1 is a block diagram of a conventional synchronization code recovery circuit;

#FIGS. 2A through 2D are timing diagrams of the synchronization code recovery circuit of FIG. 1;

#Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.

#FIG. 3 shows a synchronization code recovery circuit according to an embodiment of the present invention. The synchronization code recovery circuit includes a synchronization detector 11, a window generator 12, a synchronization location selector 13, a next synchronization pattern comparator 14, a synchronization recoverer 15, a memory 16, and a serial-to-parallel (S/P) converter 17. FIGS. 4A through 4G show timing diagrams of the synchronization code recovery circuit of FIG. 3.

#The synchronization detector 11 detects a synchronization code from an incoming serial bitstream during a window, as shown in FIG. 4C, which is generated at intervals of n channel bits by the window generator 12. Where an original synchronization code shown in FIG. 4A is damaged and no synchronization code is detected in a certain period as shown in FIG. 4B, the synchronization detector 11 provides a detection control signal to the synchronization location selector 13. In response, the synchronization location selector 13 determines a value of k to determine a number of synchronization code recovery candidates having from (n−k) to (n+k) channel bits, respectively, and transmits the determined synchronization code recovery candidates to the next synchronization pattern comparator 14. Here, n and k denote positive integers. The synchronization code recovery candidates are obtained by varying a synchronization location, that is, the number of channel bits after which the synchronization code is to be inserted. For example, where n is 100 and k is 2, 5 synchronization code recovery candidates are generated. Those are candidates having 98 channel bits, 99 channel bits, 100 channel bits, 101 channel bits, and 102 channel bits, respectively, in front of a location to which the synchronization code is to be recovered.