Currently, the smart home system flourishing era, there have been all kinds of smart home systems on the market, from a communication point of view, the mainstream smart home following categories: buses, wireless and power line carrier.
1. Smart home system based on bus communication:
RS485/CAN/FT and other bus communication technologies are used between nodes. Avoiding system architecture and other factors, this kind of smart home system is the strongest and most stable system. However, its shortcomings are also obvious. Node communication requires a dedicated communication line, and the installation and commissioning costs are the highest, especially the change. A few years ago, smart home systems basically belonged to the bus-type smart home system.
2. Smart home system based on wireless communication:
Wireless communication technology is used for communication between nodes. This is an emerging smart home system after the breakthrough in wireless communication technology in recent years. It can be divided into two main categories:
a) RF wireless communication technology represented by 315M 433M. This is the simplest and lowest cost wireless communication technology. Because of its low technology threshold and low power consumption, it can realize wireless remote control of single fire switch. Therefore, it has been widely used in the field of smart home systems. However, its shortcomings are also obvious. The ability to penetrate the wall is poor, the communication distance is too far to be received, the communication distance is too close, the saturation is blocked, the single channel communication is easy to be interfered, etc. The communication is not stable enough, which is a hard injury of the RF smart home.
b) Wireless communication technology represented by ZIGBEE/ZWAVE. This kind of wireless communication technology has self-organizing network capability, and adopts multi-channel communication, anti-interference ability and relay capability are greatly enhanced, and there is a potential for replacing the smart wireless system of RF wireless. However, its shortcomings are also obvious. Compared with the RF technology, the power consumption is larger, and it can only be made into a zero-fire switch, that is, on the basis of the conventional single-fire switch, the addition of the zero line on the cloth is required. In addition, like RF, it has the disadvantage of poor wall penetration and insufficient communication distance. Although it has the ZIGBEE relay to solve the problem of distance, as the number of relay stages increases, and the number of nodes increases, the communication quality will deteriorate, and the node drop and communication failure frequently occur.
3. Smart home system based on power communication:
The original power line is used for communication between the nodes. Power line communication is actually a kind of bus communication technology, except that it uses the original wire as the communication medium. Unlike the bus, it needs a dedicated communication bus. Its advantages are quite obvious, it can be as free of wiring as wireless, and it can communicate like a bus, and the communication distance is also greater than wireless communication. There are also many technologies for power line communication, mainly the following two:
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