C-Nav IALA, Hardware Reference Manual

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C-Nav Hardware Reference Guide
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L-band is 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 is 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 is 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.
Land Earth Station (LES) is the point on the earth’s surface where data is up linked to a
satellite.
Latitude (lat) is the north/south component of the coordinate of a point on the surface on the
earth; expressed in angular measurement from the plane of the equator to a line from the center
of the earth to the point of interest. Often abbreviated as Lat.
Least Squares Adjustment is a mathematical technique used on data sets that attempts to find
the number that provides the ‘best fit’ to the data. It does so by minimizing the sum of the
squares of the residuals, which are the difference between the estimated ‘best fit’ and the data
point squared. It is carried out using an iterative process. Furthermore, it is a method of
determining the curve that best describes the relationship between expected and observed sets
of data by minimizing the sums of the squares of deviation between observed and expected
values.
LEMO is a type of data or power connector.
Logging Interval is the frequency at which positions generated by the receiver are logged to
data files .
Longitude (long) is the east/west component of the coordinate of a point on the surface of the
earth; expressed as an angular measurement from the plane that passes through the earth’s
axis of rotation and the 0° meridian and the plane that passes through the axis of rotation and
the point of interest. Often abbreviated as Lon.
Mean Sea Level (MSL) is a vertical surface that represents sea level.
Meridian one of the lines joining the north and south poles at right angles to the equator,
designated by degrees of longitude, from 0° at Greenwich to 180°.
Meteorological (.YYm) files one of the three file types that make up the RINEX file format.
Where YY indicates the last two digits of the year the data was collected. A meteorological file
contains atmospheric information.
Monitor Station is one of five worldwide stations maintained by the DoD and used in the GPS
control segment to monitor and control satellite clock and orbital parameters. Corrections are
calculated and uploaded to each satellite at least once per day. See Control Segment.
MTSAT Satellite-based Augmentation System (MSAS is a Japanese satellite system that
provides a set of corrections for the GPS satellites, which are valid for the Japanese region.
They incorporate satellite orbit and clock corrections.
Multipath is a phenomenon whereby GPS signals from a satellite arrive at an antenna having
traversed different paths. The signal traversing the longer path may have been reflected off one