IS-GPS-800A - US Coast Guard Navigation Center

6.3.1.2 Additional L1C Overlay Code SequencesThe additional L1C O -code sequences are derived from Gold Sequences, which are the exclusive-or addition of twosequences S1 and S2. The S1 sequence is defined by one of the following four polynomials:1 + x 3 + x 6 + x 9 + x 11 Octal 5111,1 + x 4 + x 8 + x 9 + x 11 Octal 5421,1 + x + x 8 + x 9 + x 11 Octal 5403,and 1 + x 6 + x 8 + x 10 + x 11 Octal 6501.The second sequence, S2, is fixed and is defined by polynomial:1 + x 9 + x 11 Octal 5001.Each polynomial generates a sequence using a specified initial condition, e.g., S1(t) and S2(t). The additional L1C O -code sequences are then defined by L1C Oi (t) = S1(t) S2(t) for i = 64 to 210. Table 6.3-2 specifies the L1C O -codeparameters for PRN signal numbers 64 – 210. See Figure 3.2-2 for a conceptual code generator for these additionalL1C O -code sequences.105 IS-GPS-800A8 June 2010