Navman LA000645 GPS Receiver User Manual


 
LA000605D © 2007 Navman New Zealand. All rights reserved. Proprietary information and specications subject to change without notice.
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6.0 Glossary and acronyms
Axial ratio: For an electromagnetic wave having elliptical polarisation, the ratio of the
magnitudes of the major axis and the minor axis of the ellipse described by the electric eld
vector.
EMI: Electromagnetic Interference
ENIG: Electroless Nickel Immersion Gold
FR4 substrate: Flame Retardant type 4
The usual base material from which plated-through-hole and multi-layer printed circuit boards
are constructed. The type ‘4’ indicates woven glass reinforced epoxy resin.
GPS: Global Positioning System
A space-based radio positioning system that provides accurate position, velocity, and time data.
LGA: Land Grid Array
A physical interface for microprocessors. There are no pins on the chip; in place of the pins are
pads of bare gold-plated copper that touch pins on the motherboard.
LNA: Low Noise Amplier
A special type of amplier used to amplify weak signals captured by an antenna.
MCX: A type of miniature coaxial RF connector
NMEA: National Marine Electronics Association
PCB: Printed Circuit Board
RF: Radio Frequency
SDK: Software Development Kit
SMA: SubMiniature version A connectors are coaxial RF connectors developed in the 1960’s
as a minimal connector interface for coaxial cable with a screw type coupling mechanism. The
connector has a 50 Ω impedance.
SRAM: Static Random Access Memory
SMT: Surface mount technology (SMT) is a method for constructing electronic circuits in which
the components are mounted directly onto the surface of printed circuit boards
TTFF: Time-To-First-Fix
The actual time required by a GPS receiver to achieve a position solution. This specication
will vary with the operating state of the receiver, the length of time since the last position x, the
location of the last position x, and the specic receiver design.