| Term |
Definition |
Nautical Mile |
A unit of length used in sea and air navigation |
Navigation |
The act of determining the course or heading of movement. This movement could be for a plane |
Navigation Message |
The message transmitted by each GPS satellite containing system time |
NAVSTAR |
The official U.S. Government name given to the GPS satellite system. NAVSTAR is an acronym for NAVigation Satellite Timing and Ranging. |
NMEA (National Marine Electronics Association) |
A U.S. standards committee that defines data message structure |
NMEA Standard |
A NMEA standard defines an electrical interface and data protocol for communications between marine instrumentation. |
North Up Orientation |
Fixes the GPS receiver’s map display so north is always fixed at the top of the screen. |
Nroute |
Operating program for real time tracking |
P-Code |
The precise code of the GPS signal typically used only by the U.S. military. It is encrypted and reset every seven days to prevent use from unauthorized persons. |
PanTrack |
A Garmin-proprietary feature that allows the user to move the pointer and pan a track in either direction |
Parallel Channel Receiver |
A continuous tracking receiver using multiple receiver circuits to track more than one satellite simultaneously. |
Pixel |
A single display element on an LCD screen. The more pixels |
POI |
Point of interest. |
Position |
An exact |
Position Fix |
The GPS receiver's computed position coordinates. |
Position Format |
The way in which the GPS receiver's position will be displayed on the screen. Commonly displayed as latitude/longitude in degrees and minutes |
Prime Meridian |
The zero meridian |
Pseudo-Random Code |
The identifying signature signal transmitted by each GPS satellite and mirrored by the GPS receiver in order to separate and retrieve the signal from background noise. |
Pseudorange |
The measured distance between the GPS receiver and the GPS satellite using uncorrected time comparisons from satellite-transmitted code and the local receiver's reference code. |
Quadrifilar Helix Antenna |
A type of GPS antenna in which four spiraling elements form the receiving surface of the antenna. For GPS use |
Radio Technical Commission For Maritime Services (RTCM) Special Committee 104 |
A committee created for the purposes of establishing standards and guidance for interfacing between radio beacon-based data links and GPS receivers |
RAIM |
Receiver Autonomous Integrity Monitoring; A GPS receiver system that would allow the receiver to detect incorrect signals being transmitted by the satellites by comparing solutions with different sets of satellites. |
Real time tracking |
As it happens |
Route |
A group of waypoints entered into the GPS receiver in the sequence you desire to navigate them. |
RS-232 |
A serial input/output standard that allows for compatibility between data communication equipment made by various manufacturers. |
SA |
See Selective Availability. |
Sd card |
Secure digital card. |
SDIO peripherals |
Secure digital interface option - secure lock on electronic device. |
Search The Sky |
A message shown when a GPS receiver is gathering satellite almanac data. This data tells the GPS receiver where to look for each GPS satellite. |
See-Thru® Technology |
A Garmin exclusive technology which allows the various Garmin fishfinders to hear both weak and strong signals simultaneously so as to identify fish returns under the toughest conditions: suspended in thermoclines or even hiding near structures. |
Selective Availability (SA) |
The random error |
Serial Communication |
The sequential transmission of the signal elements of a group representing a character or other entity of data. The characters are transmitted in a sequence over a single line |
SOG |
See Speed Over Ground. |
SONAR |
A system using transmitted and reflected underwater sound waves to detect and locate submerged objects or measure the distance to the floor of a body of water. This technology is used in Garmin fishfinders and sounder products. |
Space Segment |
The satellite portion of the complete GPS system. |
Speed Over Ground (SOG) |
The actual speed the GPS unit is moving over the ground. This may differ from airspeed or nautical speed due to such things as head winds or sea conditions. For example |
Spread Spectrum |
The received GPS signal is wide bandwidth and low power. The L-band signal is modulated with a pseudo-random noise code to spread the signal energy over a much wider bandwidth than the signal information bandwidth. This provides the ability to receive all satellites unambiguously and to give some resistance to noise and multipath. |
Statute Mile |
A unit of length equal to 5 |
Straight-Line Navigation |
The act of going from one waypoint to another in the most direct line and with no turns. |
