GPS = Global Positioning System
Provides Speeds, direction of movement, tracking of movement, celestial positions)
GPS Unit (Garmin Map 76 – CS, Ravi’s unit) provides base map of the unit – major cities, major rivers , water bodies, airport , rail routes
Can upload tracked data to Google Earth Plus -
Requires minimum 3 GPS satellites- Uses Time triangulation concept.
Needs satellites LOS – at least 3 of them
Elevation not accurate at high speeds ( in planes)
Inside train/plane signal reception is week.
Special external antenna for car or non a/c tracking
Does not provide granular city maps.
Base map works only in APAC region
Application of GPS unit:
Tracking of movement
Rail fanning – Train speed, route tracking and recording
Analysis – More on this later.
Air fanning – Flight path tracking; mixed acceptance from pilots – some allow, some deny, some are hesitant to allow GPS on their planes.
Speed on Y axis – distance on X – Axis – Train – 2314 - NDLS – SDAH Rajdhani – Graph shows speed V/s distance plot
Another graph on NZM – SBC Rajdhani from NGP to SBC.
Analysis – Comparision of speeds by various trains on various sections. Faster speeds need not neccesarily translate to shorter travel times.
Track elavation graphs can also be plotted . Altitude on Y – Axis (Metres) & Distance (In Kms) on X – Axis. Satellite view of MAS – SBC section (GPS view of the section uploaded on Google Earth)