Trimble Outdoors SK8 - Manual (Page 203)

Lassen-SK8 Embedded GPS Module Glossary-5
Glossary
GPD GPS with differential corrections applied.
GPS Global Positioning System. A constellation of 24 radio navigation (not
communication) satellites which transmit signals used (by GPS
receivers) to determine precise location (position, velocity, and time)
solutions. GPS signals are available world-wide, 24 hours a day, in all
weather conditions. This system also includes 5 monitor ground stations,
1 master control ground station, and 3 upload ground stations.
GPS antenna An antenna designed to receive GPS radio navigation signals.
GPS processor An electronic device that interprets the GPS radio navigation signals
(received by a GPS antenna) and determines a location solution. The
GPS processor may also be able to apply (and determine) differential
GPS corrections.
GPS receiver The combination of a GPS antenna and a GPS processor.
GPS time The length of the second is fixed and is determined by primary atomic
frequency standards. Leap-seconds are not used, as they are in UTC.
Therefore, GPS time and UTC differ by a variable whole number of
seconds.
HDOP Horizontal Dilution of Precision.
HOW Handover word. The word in the GPS message that contains time
synchronization information for the transfer from C/A to P-code.
interface cable The interface cable allows data to flow between the Placer RPU and the
communication equipment. One end of the cable has a single 37-pin
connector; the other end of this cable has an 25-pin RS-232 connectors
and a set of fused red and black power leads.
interference Refers to the unwanted occurrences on communication channels that are
a result of natural or man-made noises and signals, not properly a part of
the signals being transmitted or received.
integrated Doppler A measurement of Doppler shift frequency or phase over time.
IODE Issue Of Data, Ephemeris. Part of the navigation data. It is the issue
number of the ephemeris information. A new ephemeris is available
usually on the hour. Especially important for Differential GPS operation
that the IODE change is tracked at both the reference station and mobile
stations.
jamming Interference (in either transmitting or receiving signals) caused by other
radio signals at exactly or approximately the same frequency
Kalman filter A numerical method used to track a time-varying signal in the presence
of noise. If the signal can be characterized by some number of
parameters that vary slowly with time, then Kalman filtering can be used
to tell how incoming raw measurements should be processed to best
estimate those parameters as a function of time.
masks See satellite masks.
2-D Two Dimensional. A 2-D position is defined as latitude and longitude.
Altitude is assumed to be fixed.