Databases Reference
In-Depth Information
FIGURE 9.1: A generic wireless sensor node architecture. (This figure is a
copyright of and reproduced with permission of Civil-Comp Ltd. Previously
published in [96].)
TABLE 9.1: Berkeley Mica Mote Sensor Node Specifications
Component
Specification
CPU:
8-bit 4 MHz
Memory:
128 KB Flash and 4 KB RAM
Communication:
916 MHz 40 Kbps Radio
Power:
2 AA Batteries
(This table is a copyright of and reproduced with permission of Civil-Comp
Ltd. Previously published in [96].)
using on-site computations, and they improve performance by reducing the
processing delay experienced in existing approaches.
Figure 9.1 shows a generic wireless sensor node architecture. Currently,
there are a number of commercially available wireless sensor nodes for
different types of applications. These include the Berkeley Mica Mote
(http://www.xbow.com) and the UCLA iBadge. The specifications of the
Berkeley Mica Mote sensor node, which is used in a number of surveillance
networks, are listed in Table 9.1.
On a macro level, a WSN is built up from a network of wireless sensor nodes
that are linked together through a common entity, known as the base station
or sink. Because of limited power and processing capabilities, communications
between sensor nodes and the base station usually involve a series of data
aggregation techniques to reduce the volume of tra
c enroute to the base
station.
9.1.2 DHGN-WSN Event Detection Configuration
In a fully distributed DHGN configuration, a collection of sensor nodes
collaborate and form a DHGN subnet to perform event detection based on
the sensory readings obtained from their environment. This is illustrated in
Figure 9.2.
