Novatel 01020347, User Manual

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Messages Chapter 5
WAAS GUS Signal Generator User Guide Rev 1 33
L1 Q CHANNEL G2 CODER INITIALIZATION FIELD
This field contains the initial state (10 bits) of the L1 Q Channel G2 code generator. If this field is set to zero, then
the Q Channel G2 coder does not participate in modulation. See
Table 24 on Page 33 for the Q channel G2 coder
initialization field bit format.
Table 24: L1 Q Channel G2 Coder Initialization Field
L5 I CODER INIT XB(I) FIELD
This field contains the initial state (13 bits) of the L5 I Channel XB(I) code generator. See Table 25 for the I channel
XB(I) coder initialization field bit format.
Table 25: L5 I Channel XB(I) Coder Initialization Field
L5 Q CODER INIT XB(Q) FIELD
This field contains the initial state (13 bits) of the L5 Q Channel XB(Q) code generator. If this field is set to zero,
the Q Channel XB(Q) coder does not participate in modulation.
Table 26 shows the byte and bit ordering for the Q
channel XB(Q) coder initialization field.
Table 26: L5 Q Channel XB(Q) Coder Initialization Field
5.1.3.4 Code Chip Rate and Carrier Frequency Command
The Code Chip Rate and Carrier Frequency Command specifies in absolute terms, the new Code Chip Rate and
Carrier Frequency (for either L1 or L5) to be assigned at the next 1PPS update pulse and the Code Chip Rate Ramp
and Carrier Frequency Ramp to be assigned at the update periods following the next 1PPS update pulse. The Code
Chip Ramp Rate or Carrier Frequency Ramp can be set to zero if no ramp update is to be performed every update
period (250 ms). If the Code Chip Ramp Rate is not zero, then the Code Chip Rate is adjusted by the Code Chip
Rate Ramp amount every 250 ms update period for three update periods following the next 1PPS. If the Carrier
Frequency Ramp is not zero, then the Carrier Frequency is adjusted by the Carrier Frequency Ramp amount every
250 ms update period for three update periods following the next 1PPS.
Figure 10 on Page 35 shows the
application of three ramp values (

f
n
) over 1 s application periods. The fourth one is overridden with the
application of the next Carrier Frequency value (f
n+1
). Table 27 on Page 34 shows all fields applicable to this
command.
LS Byte [15] MS Byte [16]
D7 D6 D5 D4 D3 D2 D1 D0 - - - - - - D9 D8
LSB MSB
G2Q(7) (6) (5) (4) (3) (2) (1) G2Q(0) - - - - - - G2Q(9) G2Q(8)
LS Byte [13] MS Byte [14]
D7 D6 D5 D4 D3 D2 D1 D0 - - - D12 D11 D10 D9 D8
LSB MSB
XBI(7) (6) (5) (4) (3) (2) (1) XBI(0) - - - XBI(12) 11 10 9 XBI(8)
LS Byte [15] MS Byte [16]
D7 D6 D5 D4 D3 D2 D1 D0 - - - D12 D11 D10 D9 D8
LSB MSB
XBQ(7) (6) (5) (4) (3) (2) (1) XBQ(0) - - - XBQ(12) 11 10 9 XBQ(8)