Design And Implementation Of Prototype Smart Home System Based On ZigBee

The traditional smart home system connects all the associated devices in the home system by the actual communication line. These devices include PC, security systems, illumination device, refrigerator and so on. This type of smart home is called Bus Type, which means controlling the devices by the information through the bus. It requires high quality of bus, and the number of devices connected to bus also has upper limit. If the damage to wall is not allowed or some places are not allowed to install the lines, the installation of bus type system would face great troubles. To solve these problems, this paper proposes a prototype smart home system based on ZigBee. This system changes the RS485 bus into wireless form, which greatly increases the flexible of smart home's layout. Moreover, the human-computer interaction is emphasized in this paper, which makes the user has more intuitive feeling of control through the virtual equipments.The work that this paper accomplished is as follow:1. Proposes a novel smart home model that integrates control system and wireless transceiver unit. It dose not need to connect all device by RS485 bus any more, which makes the line installation more easily. The wireless connection of all devices at home would construct a completed wireless controlled network, which eliminate the upper limit of devices number on bus. This means that we can monitor more devices than ever before.2. Designs the communication algorithm of smart home control system based on ZigBee under the wireless circumstance. Furthermore, the key algorithms for main modules of simulator are also detailed, including data decoder, data synthesis, database process etc. The frame formats in the communication protocol are also designed, such as code format and data validation. There are two models of communication, unicast model and broadcast model. The unicast model is used in the case of controlling the specified target device. And the broadcast model is used to test the work status of all devices on the line. If one device receives a data frame, the corresponding answer frame would be made and send out.3. The database is designed to store the status information of various devices. The control system updates the status of one device's iron on the interface through inquiring the database. And its data is gathered from the answer information that the devices send back to the system.4. Implement the smart home control system. The devices could be controlled by wireless signal, and the program interface is friendly. The control or debug could be performed directly through the device iron on the interface, which makes the system easier to use. Moreover, the status information of device could be send back to simulator in the form of answer frame, which makes the user know the real-time status of all devices on the line.