Apparatus and method for detecting frame synchronization signal for reducing errors in data demodulation in optical disc system

A method of detecting a frame synchronization signal in a frame synchronization signal detection apparatus of an optical disc system, the frame synchronization signal detection apparatus comprising:

• a synchronization signal detector which detects a synchronization signal from a digital data signal;
• a main frame synchronization signal generator, which outputs, as an internal frame synchronization signal, one of a first valid synchronization signal detected from the synchronization signal and an insertion synchronization signal internally generated;
• a sub frame synchronization signal generator, which detects a second valid synchronization signal, while the main frame synchronization signal generator generates the insertion synchronization signal;
• and an output unit which outputs a frame synchronization signal, in response to the internal frame synchronization signal and the second valid synchronization signal, the method comprising:
• (a) detecting the first valid synchronization signal from the digital data signal;
• (b) outputting the first valid synchronization signal as the frame synchronization signal, when the first valid synchronization signal is detected within a predetermined time interval;
• (c) generating and outputting the insertion synchronization signal as the frame synchronization signal, if the first valid synchronization signal is not detected during the predetermined time interval;
• and
• (d) returning to step (a), if the second valid synchronization signal is activated while the insertion synchronization signal is generated.