Smart home is undoubtedly one of the hot research objects in recent years. Various protocols are constantly updating the latest version and improving the shortcomings. As a result, there is currently no communication protocol for international standardization for smart home and intelligent lighting . This paper mainly compares the principles, technical features, advantages and disadvantages of various schemes and looks forward to the future of the smart home market . Below we will introduce these protocols one by one: First, the ZigBee protocol: Zigbee is the abbreviation of IEEE 802.15.4 protocol, which is derived from the bee's splayed bee. The bee is the "dance" of flying wings and "zig" shaking wings to convey the position information of the pollen with the companion, and ZigBee The characteristics of the protocol are similar to the name of ZigBee. ZigBee is mainly suitable for automatic control and remote control. It can be embedded in various devices. It is characterized by short propagation distance, low power consumption, low cost, low data rate, self-organizing network and simple protocol. The main advantages of ZigBee are as follows: Low power consumption Compared to Bluetooth and WiFi, the same power (two AA batteries) can support the device for six months to two years, while Bluetooth can only work for a few weeks, WiFi can only work for a few hours. 2. Low cost The ZigBee patent fee is waived, the transmission rate is small and the protocol is simple, which greatly reduces the cost of the ZigBee device. 3. Low drop rate Due to ZigBee's collision avoidance mechanism, and at the same time, a dedicated time gap is reserved for the fixed bandwidth of the communication service, so that competition and conflict do not occur during data transmission; the function of the self-organizing network allows each node module to be between The contact can be established, and the received information can be transmitted through the line between each node module, so that the reliability of ZigBee transmission information is greatly improved, and it can be considered that it will not be dropped. 4. Strong networking ability ZigBee's networking capabilities are superior, with 60,000 nodes each. 5. Security and confidentiality ZigBee provides a set of security classes and software based on the 128-bit AES algorithm and integrates the security elements of IEEE 802.15.4. 6. Flexible working frequency band The 2.4 GHz, 868 MHz and 915 MHz bands are all unlicensed. The disadvantages of ZigBee are as follows: Propagation distance If the power amplifier is not applicable, the effective propagation distance of ZigBee is generally 10m-75m, which is mainly suitable for some small areas, such as home and office. However, if the node module is used as the receiving end and the transmitting end is sacrificed under the premise of sacrificing the advantage of its low drop rate, long-distance information transmission can be realized. 2. Low data transmission rate In the 2.4 GHz band, ZigBee also has a propagation speed of only 250 Kb/s, and this is only the rate on the link and does not include frame header overhead, channel contention, acknowledgment and retransmission, and the actual applicable after removing these. The rate will be less than 100 Kb/s, and the rate will be shared by multiple nodes when running multiple applications. PZT Piezoelectric Cylinders/Tubes
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