Zigbee is a wireless data transmission network platform consisting of as many as 65,000 wireless data transmission modules. Within the whole network, all Zigbee network data transmission modules can communicate with each other, and the distance between network nodes can extend infinitely from the standard 75m.
Different from CDMA network or GSM network for mobile communication, Zigbee network is mainly established for automatic data transmission in industrial field, so it must be simple, convenient, reliable and low-cost. The mobile communication network is mainly established for voice communication, and the value of each base station is generally more than one million yuan, while each Zigbee "base station" is less than 1000 yuan. Each Zigbee network node can not only be used as a monitoring object, for example, its connected sensors can directly collect and monitor data, but also can automatically transmit data from other network nodes. In addition, each Zigbee network node (FFD) can also wirelessly connect a number of isolated child nodes (RFD), which do not undertake the task of network information transmission within their own signal coverage.
Advantages of ZigBee
① Low power consumption. In low-power standby mode, two No.5 dry batteries can support 1 node to work for 6 ~ 24 months, or even longer. This is the outstanding advantage of Zigbee. In comparison, Bluetooth can only work for a few weeks, and WiFi can only work for a few hours.
② Low cost. By greatly simplifying the protocol (less than Bluetooth's110), the requirements for the communication controller are reduced. According to the prediction and analysis, based on the 8-bit microcontroller of 805 1, the full-function master node needs 32KB code, the sub-function node only needs 4KB code, and Zigbee is free of protocol patent fees. The price of each chip is about 2 dollars.
③ Self-organizing network. Zigbee protocol adopts mesh network topology, automatically joins the network, automatically discovers routes, and quickly heals itself when nodes are disconnected.
4 long distance. Zigbee can pass up to 256 routes, and the distance between each node can reach 1.6KM, thus realizing wireless expansion.
⑤ Large capacity. Zigbee can adopt star, sheet and mesh network structure. A master node can manage multiple child nodes, and a master node can manage up to 254 child nodes. At the same time, the master node can also be managed by the upper network nodes, which can form a large network with up to 65,000 nodes.
⑦ High safety. Zigbee provides three-level security modes, including no security settings, using access control list (ACL) to prevent illegal access to data, and using symmetric password of advanced encryption standard (AES 128) to flexibly determine its security attributes.
Infiltration of Zigbee and Bluetooth
1. Both technologies use the 2.4GHz frequency band.
The ability to penetrate walls is weak.
The difference is that ZigBee uses DSSS spread spectrum and Bluetooth uses FHSS spread spectrum.
The decision of DSSS and FHSS depends on the positioning of products in the market, because it can solve the transmission capacity and characteristics of WLAN, including anti-interference ability, application range, bandwidth size and transmission data size. DSSS technology is suitable for fixed environments or applications that require high transmission quality. Therefore, most wireless factories, wireless hospitals and network communities use DSSS wireless technology products. However, FHSS is mostly used for endpoints that need to move quickly, such as mobile phones, and its wireless transmission technology adopts FHSS spread spectrum technology.
2. As far as the recognized transmission distance is concerned, ZigBee is about 70m, and Bluetooth is within 10m (but at present, zigbeePRO and ADV can reach an open communication distance of 2KM, which is farther than Bluetooth technology).
Within their respective effective ranges, Bluetooth should have a slightly stronger ability to penetrate walls, because Bluetooth devices are useful.
The transmission power is definitely higher than ZigBee.
3. It is difficult to improve the wall, I don't know what you want to do;
It is common to relay and forward data by adding routing equipment to bypass obstacles.
In this respect, ZigBee has advantages, because there is the concept of router in ZigBee technology.
Bluetooth, I don't think so. I haven't heard of it.