فناوری بی سیم Zigbee, وای فای و 433 مگاهرتز ویژگی های آنها

فناوری بی سیم Zigbee, وای فای و 433 مگاهرتز ویژگی های آنها

Zigbee, WiFi و 433MHz سه فناوری مختلف برای ارتباطات بی سیم با برد کوتاه هستند. هر فناوری جوانب مثبت و منفی خود را دارد.

Zigbee یک قدرت کم است, بسیار قابل اعتماد, فناوری شبکه شبکه بی سیم. با استفاده از روترها, نه تنها منطقه پوشش شبکه به راحتی قابل گسترش و تنظیم است, but also the “blind spot” in wireless communication environment can be eliminated. علاوه بر این, Zigbee supports star, tree and mesh topologies. از این رو, Zigbee is well-suited for both simple and complex built environment. Compared to the WiFi, با این حال, Zigbee’s data rate is 250kbps, lower than WiFi’s 11Mbps-54Mbps. That makes Zigbee inappropriate for high data rate applications, such as internet surfing, large file downloading or uploading. For restaurant and catering industry, با این حال, the data exchanged between server and terminals generally are just small amount. از این رو, Zigbee is a quite suitable technology for ordering application.

WiFi can support high-data-rate applications. It also supports “always-on” feature, which makes the WiFi attractive for some applications. با این حال, it has some drawbacks which have been noticed by the consumers, such as high power consumption, low reliability, long reconnection time, و غیره.

433MHz technology has been widely used in China for restaurant ordering application. Since it uses relatively low frequency band, its wireless signal can be transmitted further than Zigbee and WiFi, which operates in 2.4GHz band. با این حال, the data rate of 433MHz is only 9.6kbps, much lower than WiFi and Zigbee’s data rate. از این رو, 433MHz suits the application in which only small amount of data needs to be transmitted. علاوه بر این, same as WiFi, 433MHz supports star topology only, which may cause “blind spot” within the wireless network coverage area.

Different from the WiFi’s “always-on” feature, in Zigbee and 433MHz system, the wireless link is established only when there is data need to be transmitted. This mechanism can dramatically reduce the interference to other devices in the network. The power consumption of the device is also reduced. با این حال, If “always-on” is requested in Zigbee or 433MHz system, a function can be designed in the application software to support this feature.
(منبع: Shehzhen Seabreeze Smart Card Co.,Ltd.)