Technology Behind Location Awareness CST 594- Mobile Computing Team members Agastheswar Suribhatla Eshwari Mente. Overview. Global Positioning System Location Estimation with 802.11 Cellular Based System Improving Location Accuracy Location Based Applications and Services
GPS Architecture has three distinct parts
Location based systems can be grouped to four categories
Various ways accuracy improvement techniques:
1. Smoothing - Damp out errors and improves accuracy
Another error reducing technique is to constrain coordinate
based location estimate using natural boundaries in physical
eg GPS based in-car navigation systems.
Fig 1: Uses Infrared(small squares) and Ultrasonic (circles) beacons to locate the user.
Fig 2: Schematics of multistory building
Uses two or more different types of sensor observation to determine location of the device.
Bayes filter perform state estimate on a dynamic system when there is uncertainty due to noise in the evidence being collected.
Bayes filters are used to estimate the chance of a device being in a given location having seen the sequence of sensor reading (E1, E2,E3..)
Accuracy of a location system using particle filter fusion of infrared
beacon and ultrasonic ranging observation.
1. Navigation And Way- Finding:
Real- time fleet management maps.
One of the highest value application of location technology is to aid in assisting individual who may be lost, hurt or damage.
Assert tags capable of providing real time location information.
1. Mobile devices deployed are not equipped with a location system.
Fortunately, there are free commercial libraries that perform wide area location estimation without addition hardware.
2. Developers facing difficulties in designing location-enhancing interactions and testing them in various of condition.
Topiary allows rich location based interaction to be designed, tested and quickly iterated.
3. Most importantly Privacy.