Is zigbee technology easy to learn? What basic knowledge is needed?

Zigbee is a new wireless network technology with short distance, low rate and low power consumption. It is a technical scheme between wireless tag technology and Bluetooth. Previously known as "HomeRF Lite" or "FireFly" wireless technology, it is mainly used for short-range wireless connection. He has his own radio standard, which realizes the communication between thousands of tiny sensors. These sensors only need very low power consumption and relay data from one sensor to another through radio waves, so their communication efficiency is very high. Finally, these data can be analyzed by computers or collected by other wireless technologies such as WiMax. The foundation of Zigbee is IEEE802. 15.4, which is a standard of IEEE personal area network (PAN) working group and is called IEEE802. 15.4 (ZigBee) technical standard.

Zigbee is not just the name 802. 15.4. IEEE only deals with the underlying MAC layer and physical layer protocols, so the Zigbee Alliance has standardized its network layer protocols and APIs (as shown in Figure 2 below). The complete protocol is used for 4K bytes that can be directly connected to the basic node of the device at one time, or 32K bytes that can be used as a hub or router coordinator. Each coordinator can connect up to 255 nodes, and several coordinators can form a network, and there is no limit to the number of routing transmissions. The Zigbee Alliance has also developed a security layer to ensure that this portable device will not accidentally reveal its identity, and this long-distance transmission using the network will not be obtained by other nodes. The main features of Zigbee technology include the following parts:

* Low data transmission rate: only 10k/s to 250k/s, focusing on low transmission applications;

* Low power consumption: In low power standby mode, two ordinary No.5 dry batteries can be used for 6 months to 2 years, avoiding the trouble of charging or frequent battery replacement. This is also a unique advantage that Zigbee supporters have always been proud of;

* Low cost: Due to the low data transmission rate and simple protocol of Zigbee, the cost is greatly reduced. The Zigbee protocol is free of patent fees.

* Short delay: usually the delay is between15ms and 30ms;

* security: Zigbee provides data integrity check and authentication functions, and the encryption algorithm adopts AES- 128, so the security attribute can be determined flexibly;

* Large network capacity: each Zigbee network can support up to 255 devices, that is, each Zigbee device can be connected with another 254 devices;

Excellent network topology ability: ZigBee has the ability of star, tree and cluster network structure. ZigBee devices actually have the self-healing ability of wireless networks, and can simply cover a wide range.

* Small effective range: the effective coverage range is between 10 and 75 meters, depending on the actual transmission power and various application modes, which can basically cover ordinary family or office environment;

* Flexible working frequency band: the frequency bands used are 2.4GHz (global), 868MHz (Europe) and 9 15MHz (United States), all of which are unlicensed.