Technical data

Tables
DSR Data Set Ready (serial communication handshaking)
DTR Data Terminal Ready (serial communication handshaking)
ECEF Earth Centred Earth Fixed.
Ellipsoidal
Height
Height as defined from the Earth’s centre by a reference
ellipsoid model (see Datum)
EMI/EMS/EMC Electromagnetic Interference (emitted from equipment),
Susceptibility (to interference from other equipment), and
Compatibility (EMI + EMS)
EPS Emergency Power Supply, only for maintaining the RTC data
in the RAM when the equipment is powered down
ENU East North Up (the order of listing co-ordinates)
Ephemeris Similar to Almanac, but providing very accurate orbital data of
each individual satellite and transmitted by the satellite
concerned
Firmware Term used for embedded software not easily upgraded by the
user (e.g. in EPROM not on disk)
GDOP Geometrical Dilution of Precision
Geoid The Mean Sea Level surface of the Earth
Geoid/
Ellipsoid
separation
Difference between the Mean Sea Level and the mathematical
model used to define a datum, at the point of interest
GMT Greenwich Mean Time (similar to UTC)
GPS Global Positioning System
GPS time Time standard for the GPS system (seconds are synchronous
with UTC)
Hex Denotes a number in hexadecimal format.
GPS Timing Receiver Installation and Operation Manual
E-3