Optimization of synchronization control in concatenated decoders

A method for synchronizing a decoder to a concatenated forward error correction coded digital signal, comprising the steps of:

• receiving a digitally encoded signal having concatenated forward error correction coding;
• synchronizing to a first layer of the concatenated forward error correction coded signal;
• synchronizing to a second layer of the concatenated forward error correction coded signal;
• synchronizing to a third layer of the concatenated forward error correction coded signal;
• disabling the first layer synchronization when the second layer is synchronized to so that the second layer synchronization determines synchronization of the decoder for both the first and second layers of the forward error correction coded digital signal;
• and
• disabling the second layer synchronization when the third layer is synchronized to so that the third layer synchronization determines synchronization of the decoder for the first, second and third layers of the forward error correction coded digital signal.

A method for decoding a concatenated forward error correction coded digital video signal, comprising the steps of:

• receiving a digital video signal having concatenated forward error correction coding;
• synchronizing to the received concatenated forward error correction coded digital video signal;
• decoding the digital video signal in a first decoder, the first decoder having a first signal output;
• synchronizing to the first signal from the output of the first decoder;
• deinterleaving the first signal;
• decoding the first signal in a second decoder, the second decoder having a second signal output;
• synchronizing to the second signal from the output of the second decoder;
• decoding the second signal in a third decoder, the third decoder having a third signal output;
• and
• disabling synchronization to the first signal when the second signal is in synchronization, wherein the second signal determines synchronization for both the first and second decoders.

An apparatus for synchronizing a decoder to a concatenated forward error correction coded digital signal, comprising:

• a first synchronizing circuit that synchronizes a first decoder to a first layer of the concatenated forward error correction coded signal;
• a second synchronizing circuit that synchronizes a second decoder to a second layer of the concatenated forward error correction coded signal;
• and
• a third synchronizing circuit that synchronizes a third decoder to a third layer of the concatenated forward error correction coded signal;
• said second synchronizing circuit disabling said first synchronizing circuit when the second layer is synchronized to, wherein the second synchronizing circuit determines synchronization for both the first and second decoders.

An apparatus for decoding a concatenated forward error correction coded digital video signal, comprising:

• a first decoder having a first signal output;
• a first synchronizing circuit that synchronizes said first decoder to the concatenated forward error correction coded digital video signal;
• a second decoder having a second signal output;
• a second synchronizing circuit that synchronizes said second decoder to the first signal from the output of said first decoder;
• a third decoder having a third signal output;
• a third synchronizing circuit that synchronizes said third decoder to the second signal from the output of said second decoder;
• and
• said second synchronizing circuit disabling said first synchronizing circuit when said second decoder is synchronized, wherein the second synchronizing circuit determines synchronization for both of said first and second decoders.