1、中文 3480 字 英文资料翻译 ZigBee/IEEE 802.15.4 Networking Examples ZigBee networking has a diverse range of applications, including but not limited to home automation, inventory tracking, and healthcare. This chapter reviews a number of the application scenarios in which ZigBee devices can increase efficienc
2、y and/or reduce cost. Full ZigBee protocol implementation has the advantage of reliable mesh networking capability. However, if the application is simple, it might be possible to implement only IEEE 802.15.4 layers. 2.1 Home Automation Home automation is one of the major application areas for ZigBee
3、 wireless networking. In this section, a number of these use cases are reviewed. The typical data rate in home automation is only 10Kbps. Figure 2.1 shows some of the possible ZigBee applications in a typical residential building. Most of the applications shown in Figure 2.1 are briefly reviewed in
4、this chapter. 2.1.1 Security Systems A security system can consist of several sensors, including motion detectors, glass-break sensors, and security cameras. These devices need to communicate with the central security panel through either wire or a wireless network. ZigBee-based security systems sim
5、plify installing and upgrading security systems. Despite ZigBees low data rate, it is still possible to transfer images wirelessly with acceptable quality. For example, ZigBee has been used in a wireless camera system that records videos of visitors at a homes front door and transmits them to a dedi
6、cated monitor inside the house. 2.1.2 Meter-Reading Systems Utility meters need to be read on a regular basis to generate utility bills. One way to do so is to read the meters manually at homeowners premises and enter the values into a database. A ZigBee-based automatic meter-reading (AMR) system ca
7、n create self-forming wireless mesh networks across residential complexes that link meters with utilities corporate offices. AMR provides the opportunity to remotely monitor a residences electric, gas, and water usage and eliminate the need for a human visiting each residential unit on a monthly bas
8、is. An AMR can do more than simply deliver the total monthly usage data； it can gather detailed usage information, automatically detect leaks and equipment problems, and help in tamper detection. ZigBee-based wireless devices not only perform monitoring tasks, they can manage the usage peak by commu
9、nicating with the appliances inside the house. For example, when there is a surge in electricity usage, a ZigBee-enabled electric water heater can be turned off for a short period of time to reduce the peak power consumption. 2.1.3 Irrigation Systems A sensor-based irrigation system can result in ef
10、ficient water management. Sensors across the landscaping field can communicate to the irrigation panel the soil moisture level at different depths. The controller determines the watering time based on moisture level, plant type, time of day, and the season. A distributed wireless sensor network elim
11、inates the difficulty of wiring sensor stations across the field and reduces the maintenance cost. 2.1.4 Light Control Systems Light control is one of the classic examples of using ZigBee in a house or commercial building. In traditional light installation, to turn on or off the light it is necessar
12、y to bring the wire from the light to a switch. Installation of a new recess light, for example, requires new wiring to a switch. If the recess light and the switch are equipped with ZigBee devices, no wired connection between the light and the switch is necessary. In this way, any switch in the hou
13、se can be assigned to turn on and off a specific light. Figure 2.2 is an example of wireless connections between wall switches and lights. In our example, the lights are located in a residential building entrance, living area, and hallway. The wall switch in the entrance can turn on and off any of t
14、he four lights. The living area wall switch, in contrast, communicates only with the lights in the living area. Living area lights are in close proximity to each other, and therefore a single ZigBee device can be used for both lights. The concept of using binding tables (see Section 1.12) is applica
15、ble in the example of Figure 2.2. Wall switch 1 is logically connected to all four lights. Wall switch 2 is bound only to the lights in the living area. One of the devices in the network has the task of storing and updating the binding table. A ZigBee-enabled recess light can be more expensive than a regular recess light, but the installation cost of a ZigBee-enabled light is lower because it requires no
