NorthStar 2201, Installation Manual

Page: 36 / 54

SECTION FOUR Using WAAS with Northstar’s 941/951/952
Page 28 2201 INSTALLATION MANUAL, Revision B
Figure 5: GPS SATS screen
Note that the WAAS satellite numbers on the
GPS SATS
screen
don’t match the pseudo random number (PRN) assigned by the
U.S. government to identify the actual satellites. For example,
the AOR (Atlantic Operating Region) satellite is “PRN 122,” but
the 941/951/952 displays it as “35.”
The satellite numbers that the 941/951/952 displays are just an
extension of the normal GPS constellation, which has 32
satellites. The 941/951/952 continues this numerical sequence
by using the number 33 for the first WAAS satellite, which
corresponds to PRN 120 (the lowest WAAS PRN assigned). See
Table 4 below for the 941/951/952 satellite equivalents for the
PRN’s.
GPS
satellite
number
WAAS
satellite
number
Table 4: PRN satellite equivalents
PRN
120 121 122 123 124 125 126 127 128 129
ON GPS
SATS
SCREEN
33 34 35 36 37 38 39 40 41 42
PRN
130 131 132 133 134 135 136 137 138
ON GPS
SATS
SCREEN
43 44 45 46 47 48 49 50 51