GALILEO - Understanding GPS: Principles and Applications - page 570

( 2+1)/2

Alt-BOC sc (t)
E5-d

1

Alt-BOC sc (t)

E5-P

1/2

( 2 − 1)/2

0

− ( 2 − 1)/2

− 1/2

− 1

− ( 2+1)/2

3/4

0 1/4 1/2 1

t/T sc E5

Figure 10.3 Periodic AltBOC modulation subcarrier functions.

Table 10.5 AltBOC Modulation Subcarrier Coefficients

k 1 2 3 4 5 6 7 8

2 ⋅ a k 21 + 1 − 1 −− 21 −− 21 − 1 1 21 +

2 ⋅ b k −+ 211 − 1 21 − 21 − − 1 1 −+ 21

Table 10.6 Distribution
of E5 Useful Power Among
Channels

Relative
Signal Power Channel

E5a-d 25%

E5a-p 25%

E5b-d 25%

E5b-p 25%

1. E5a single sideband reception;
2. E5b single sideband reception;
3. E5 (or E5a

+ E5b) wideband reception.

As a matter of fact, the E5a signal can be received and processed in isolation
from the E5b signal, as if it was transmitted alone as a signal with in-phase and
quadrature components according to the following:

( )

( ) ( ) ( )

t

s t − τ × cos 2 π f − ∆ f t − τ + θ −

x

()

r r Ead 5 - Ea 5 Ea 5 Ea 5 E 5 a E a 5

s t = 2 P ⋅

x x

( )

(

( )( )

)

Ea 5 Ea 5 t

s t − τ × sin 2 π f − ∆ f t − τ + θ

x

Ea 5 Ea 5 Ea 5 Ea 5 Ea 5

Eap 5 -