Galileo OS SIS ICD.indd - GSA - Europa

�� t A S rect �t�iT8� � �
s cE5�
S � i TS
E / 8
8
, 5
i��
�
�� t A P rect �t�iT8� � �
s cE5�
P � i TS
E / 8
8
, 5
i��
�
The coeffi cients ASi and APi are according to Table 5.
s,
E5
s,
E5
i 0 1 2 3 4 5 6 7
6 © European Union 2010
Document subject to terms of use and disclaimers p. ii-iii
OD SIS ICD, Issue 1, February 2010
Eq. 5
2 ASi 2 �1 1 -1 � 2 �1
� 2 �1
-1 1 2 �1
2 APi � 2 �1
1 -1 2 �1 2 �1
-1 1 � 2 �1
Table 5. AltBOC Subcarrier Coeffi cients
One period of the sub-carrier functions sc E5-S and sc E5-P is shown in Figure 4.
Figure 4. One Period of the Two Subcarrier Functions Involved in AltBOC Modulation
2.3.1.3. Equivalent Modulation Type
Equivalently, the AltBOC complex baseband signal s E5(t) can be described as an 8-PSK
signal according to Eq. 6. The corresponding phase states are illustrated in Figure 5.
sE 5
�
�
�
�
4
�
�
�
�� t � exp j k��
t with k��
t � �1, 2,
3,
4,
5,
6,
7,
8 �,
Figure 5. 8-PSK Phase-State Diagram of E5 AltBOC Signal
Eq. 6