NavCom SF-2040 Rev.F - Manual (Page 85)

SF-2040 User Guide – Rev. F
correct for changes in the earth’s period of rotation.
As of September 2002 GPS time is 13 seconds
ahead of UTC.
Greenwich Mean Time (GMT) the local time of the
0° meridian passing through Greenwich, England.
HAE see altitude, and ellipsoid.
IODC Issue of Data, Clock - The IODC indicates the
issue number of the data set and thereby provides
the user with a convenient means of detecting any
change in the correction parameters. The transmitted
IODC will be different from any value transmitted by
the satellite during the preceding seven days.
JPL Jet Propulsion Laboratory.
Kbps kilobits per second.
L-Band the group of radio frequencies extending
from approximately 400MHz to approximately
1600MHz. The GPS carrier frequencies L1
(1575.4MHz) and L2 (1227.6 MHz) are in the L-Band
range.
L1 carrier frequency the primary L-Band carrier
used by GPS satellites to transmit satellite data. The
frequency is 1575.42MHz. It is modulated by C/A
code, P-code, or Y-code, and a 50 bit/second
navigation message. The bandwidth of this signal is
1.023MHz.
L2 carrier frequency the secondary L-Band carrier
used by GPS satellites to transmit satellite data. The
frequency is 1227.6MHz. It is modulated by P-code,
or Y-code, and a 50 bit/second navigation message.
The bandwidth of this signal is 10.23MHz.
lat see latitude.
latitude (lat) the north/south component of the
coordinate of a point on the surface on the earth;
expressed in angular measurement from the plane of
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