Galileo (GIOVE-A) E6 Commercial Service BPSK Code Generators
Grace Gao, Jim Spilker,
Dennis Akos, Sherman Lo, Alan Chen, and Per Enge
The GIOVE-A and proposed
GALILEO E6 signal is composed to three signals. Two Commercial
Service (CS) codes and Public Regulated Service (PRS) code are provided.
The CS codes were found to be inphase and modulated using BPSK (5.115
Mcps). The result is that the CS signal has three stages: 1 0 -1
since it is the addition of two in phase BPSK signals. The PRS
code is modulated using BOC (10,5).
•
•Results:
-
–Both
codes are linear codes
-
–Each
code is generated by a 26 order polynomial
-
–Factorize
obtained code generator polynomials
-
–The
code sequence can be generated by modulo 2 addition of maximal length
sequences of the factor polynomials
E6-B code:
5115 bits, 1ms, Gold code
Polynomial 1: X13+X12+X11+X1+1
Initial state: [0 1 0 1 0 1 1 1 0 0 0 0 0]
Polynomial 2: X13+X10+X8+X5+1
Initial state: [1 1 1 1 1 1 1 1 1 1 1 1 1]
E6-C code: (primary code) x
(secondary code) = 511500 bits, 100ms
Primary code: 10230 bits,
2ms, Gold code
Polynomial 1: X14 +X8+X7+X4+X3+X2+1
Initial state: [0 1 1 0 1 0 0 0 0 1 1 1 0 1]
Polynomial 2: X14+X11+X6+X1+1
Initial state: [1 1 1 1 1 1 1 1 1 1 1 1 1 1]
Secondary code: 50 bits
[0 1 0 1 1 1 1 1 1 0 0 1 0 1 1 1 0 1 0 1 1 0 0 0 0 1 0 0
1 0 1 0 0 0 0 1 1 1 0 1 1 0 0 1 1 0 0 0 1 0];
|
Giove-A broadcast codes |
Type |
Length |
Period |
Generated by |
With data? |
|
L1 BOC (1,1) codes |
L1-B |
Truncated Gold code |
4092 |
4 msec |
Two 13-stage LSRs |
Yes |
|
L1-C |
Primary |
Truncated Gold code |
8184 |
8 msec |
Two 13-stage LSRs |
No |
|
Secondary |
|
25 |
200 msec (With Primary) |
|
|
|
E6 BPSK codes |
E6-B |
Truncated Gold code |
5115 |
1 msec |
Two 13-stage LSRs |
Yes |
|
E6-C |
Primary |
Truncated Gold code |
10230 |
2 msec |
Two 14-stage LSRs |
No |
|
Secondary |
|
50 |
100 msec (With Primary) |
|
|
Table 1. Summary of Assessment
of the GIOVE-A L1, E6 Code
LINKS
For details on how the SGMS results were verified,
CONTINUE
Back to GIOVE-A L1 OS Code, CONTINUE
On to GIOVE-A E5 Code, CONTINUE
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