21-06-2013, 03:27 PM
A Mobile GPRS-Sensors Array for Air Pollution Monitoring
A Mobile GPRS.pdf (Size: 723.49 KB / Downloads: 48)
Abstract
An online GPRS-Sensors Array for air pollution
monitoring has been designed, implemented, and tested. The
proposed system consists of a Mobile Data-Acquisition Unit
(Mobile-DAQ) and a fixed Internet-Enabled Pollution Monitoring
Server (Pollution-Server). The Mobile-DAQ unit integrates a
single-chip microcontroller, air pollution sensors array, a General
Packet Radio Service Modem (GPRS-Modem), and a Global Positioning
System Module (GPS-Module). The Pollution-Server is a
high-end personal computer application server with Internet connectivity.
The Mobile-DAQ unit gathers air pollutants levels (CO,
NO2, and SO2), and packs them in a frame with the GPS physical
location, time, and date. The frame is subsequently uploaded to
the GPRS-Modem and transmitted to the Pollution-Server via the
public mobile network. A database server is attached to the Pollution-
Server for storing the pollutants level for further usage by
various clients such as environment protection agencies, vehicles
registration authorities, and tourist and insurance companies. The
Pollution-Server is interfaced to Google Maps to display real-time
pollutants levels and locations in large metropolitan areas. The
system was successfully tested in the city of Sharjah, UAE. The
system reports real-time pollutants level and their location on a
24-h/7-day basis.
INTRODUCTION
MANY air pollution systems in urban and rural areas
that utilize smart sensor networks and wireless systems
were reported in recent literature. An environmental air pollution
monitoring system that measures CO, NO2, and SO2 was
reported [1]. The system is based on a smart sensor microconverter
equipped with a network capable application processor
that downloads the pollutants level to a personal computer for
further processing. A wearable and wireless sensor system for
real-time monitoring of toxic environmental volatile organic
compounds was developed in [2]. An air pollution geo-sensor
network consisting of 24 sensors and 10 routers was installed
to monitor several air pollutants in [3]. The system provides
alarm message depending on the detected pollution types in
the field. A high-resolution surveillance Web-camera was used
to monitor air quality via the Internet [4].
HARDWARE ARCHITECTURE
To satisfy the system’s functional and nonfunctional requirements,
two major building blocks are needed, namely: a Mobile
Data-Acquisition Unit (Mobile-DAQ) and a fixed Internet-Enabled
Pollution monitoring Server (Pollution-Server).
The Mobile-DAQ unit is designed by integrating the following
hardware modules shown in Fig. 1. As the figure
shows, the Mobile-DAQ consists of a 16-bit single-chip microcontroller
integrated with a sensor array using analog ports.
The Mobile-DAQ is also connected to a GPS module and
a GPRS-Modem using the RS-232 interface. Each of these
components is described in the following
GPRS-Modem
The general packet radio service (GPRS) is a packet-oriented
mobile data service used in 2G and 3G cellular communication
systems global system for mobile communications (GSM).
The proposed system uses a GPRS-Modem as a communication
device to transmit time, date, physical location and
level of air pollutants. The modem used for the proposed
system has an embedded communication protocol that supports
Machine-to-Machine (M2M) intelligent wireless Transmission
Control Protocol (TCP/IP) features such as Simple Mail
Transfer (SMTP) E-mail, File Transfer Protocol (FTP), and
Simple Messaging Service (SMS) services Protocol. The
modem supports an RS-232 interface that allows Serial TCP/IP
socket tunneling. The modem also has rugged aluminum enclosure
making it suitable for the proposed system [12].
IMPLEMENTATION AND TESTING
The Environment Protection and Safety Section (EPSS) in
Dubai has monitored air quality since 1988 [14]. Their current
system is based on six static monitoring stations located around
the Dubai metropolitan area. These stations send air pollutant
data to a central server using fixed line modem connections. The
pollution data is also available to the public through their Web
site. This system has worked well. However, the data collected
is limited to the vicinity of the six monitoring stations. Consequently,
a mobile system based on the hardware and software
architecture described earlier was built and tested in the UAE.
CONCLUSION
A wireless distributed mobile air pollution monitoring system
was designed, implemented and tested using the GPRS public
network. The system utilizes city buses to collect pollutant gases
such as CO, NO2, and SO2. The pollution data from various mobile
sensor arrays is transmitted to a central several that make
this data available on the Internet through a Google Maps interface.
The data shows the pollutant levels and their conformance
to local air quality standards. It is worth mentioning that much
more work is required to commercialize the system.