Indicating end of idle sequence by replacing expected code words while maintaining running disparity

摘要

Methods and systems for indicating an end of an idle sequence residing between first and second frames, while maintaining bounded running disparity, including: encoding the first frame; encoding a basic idle sequence utilizing a first line-code; producing an idle sequence by replacing M code words of the basic idle sequence with M alternative code words; encoding the second frame; transmitting the first frame, the idle sequence, and the second frame; and receiving the second frame by a second communication node. Each one of the M alternative code words is equal to a code word of the basic idle sequence. And the second communication node is unable to determine a starting point of the second frame based only on the idle sequence and the second frame, but is able to determine the starting point of the second frame based on difference between the basic idle sequence and the idle sequence.

主权项

1. A communication system comprising:
a first node configured to communicate with a second node; the first node comprises an encoder and a transmitter; the encoder is configured to encode a first frame, an idle sequence including X code words, and a second frame; the encoder is further configured to determine X minus M code words of the idle sequence to be equal to X minus M code words of a basic idle sequence; wherein the basic idle sequence is obtained utilizing a first line-code having a binary code word length N_idle; the encoder is further configured to determine remaining M code words of the idle sequence to be alternative code words, wherein each alternative code word is equal to at least one code word of the basic idle sequence; the encoder is further configured to maintain over the idle sequence absolute value of running disparity lower than or equal to K, wherein K is lower than N_idle/2; the transmitter is configured to transmit the first frame, idle sequence, and second frame; the second node is characterized by not being able to determine a starting point of the second frame based only on the idle sequence and the second frame; and the second node is further characterized by being able to determine the starting point of the second frame based on difference between the basic idle sequence and the idle sequence.