| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and apparatus for transmitting and receiving Forward Error Correction (FEC) frame headers with variable header modulation.SOLUTION: This 32-symbol header is used when a PLP data portion is modulated with 16-QAM or 64-QAM data symbols. The 16 signaling bits are coded using RM(32,16) code. The resulting 32 codeword bits are modulated by BPSK in a modulator using a 32-bit PRBS. The RM(32,16) codeword undergoes a 1-bit cyclic shift and is exclusive-ORed with the 32 bits to form a sequence which is used to indicate in-phase or quadrature-phase BPSK.SELECTED DRAWING: Figure 2 |
