Remote Sensing Accuracy Trade-Off for Continuous Mobile Device Location

Abstract

Location is a fundamental service for mobile computing. Typical GPS receivers, although widely available for navigation purposes, may consume too much energy to be useful for many applications. Observing that in many sensing scenarios, the location information can be post-processed when the data is uploaded to a server, we designed a  solution that allows a sensing device to aggressively duty-cycle its GPS receiver and log just enough raw GPS signal for post-processing. Leveraging publicly   available information such as GNSS satellite ephemeris and an Earth elevation database, a cloud service can derive good quality GPS locations from a few milliseconds of raw data.  It can collect CO2 concentration, temperature, humidity, light intensity and other air environmental information through sensors and get the current position (longitude, latitude and elevation) and timing (GMT) information through Global Positioning System (GPS). Each node will then transmit the data to the monitoring station. The GSM network will send the collected data to the data center server. The system uses a compact circuitry built around microcontroller programs are developed in Embedded C. Flash magic is used for loading programs into Microcontroller