1.2.3.2.Examples of application of wireless sensor networks
The smart grid is an electrical grid that represents a next-generation electrical power system; it maximizes the use of information technology and communications, releases, and energy consumption. The sensors and LR-WPAN devices in terms of IEEE 802.15.4 add to power lines and are used in substations as well. Remote monitoring and managing the smart grid reliability can be maintained with the help of such automation. The combinations of IEEE 802.15.4 and its amendment IEEE 802.15.4g application scenario are shown in Fig. 1.8.
Figure 1.8. Combinations of IEEE 802.15.4 and IEEE 802.16 application scenario [5]
IEEE 802.15.4 LR-WPAN convinces the requirements of wide range of applications. The current industrial market is using a lot LR-WPAN networks. With the use of wireless sensors and LR-WPAN devices together, information is collected, forwarded and analyzed. For example, wireless sensors and LR-WPAN devices can be placed at factories and industries to find out last-minute problems such as fires and risky chemical balances, and also be positioned in machinery to monitor and control regular operations. In short, the emphasis is monitoring in industrial applications where frequent updating and higher throughput is not the case. The longer battery powered devices are the key factor and they can get by on lower power consumption.
Automotive sensing minimizes the cost of wiring installation in vehicles and makes flexible connections. It has many applications, including tire pressure monitoring, smart badges and tags. For tire pressure monitoring, it is required to place four sensors on each tire.
These sensors forward the data or commands about the pressure changes every few miles to a central station, allowing drivers to take necessary steps based on the data. Once these sensors are battery powered, it is a completely wireless communications. There will be fewer bits of data and therefore, the life of battery-powered sensors can be longer. It is good if switching batteries are not necessary before the tires are replaced.
Home automation and networking is the fundamental and primary application of LRWPAN where they perfect fit compared to other IEEE standards or protocols. The star topology is preferable in this network due to presence of 50 to 100 devices. Pure home automation, consumer electronics, PC peripherals, health monitoring, toys and games are considered under this section.
In the home automation example, lighting monitoring, security system control, door and window locks, curtain controls, and HVAC (Heating, Ventilation and Air Conditioning) technology can be taken into account. Remote control, televisions, radios, VCRs, CDs, and DVDs come under the consumer electronics type. LR-WPAN makes an adaptable remote control to handle all of them. PC peripherals can use Bluetooth technology sometimes, but they typically use LR-WPAN devices such as wireless mice, keyboards, joysticks, PDAs with low-end inputs, and multimedia games. The requirements range for latency and throughput for PC peripherals are 15ms to 100ms and 10kbps to 115kbps, thus they are suitable for the LR-WPAN application.