工業(yè)應用中2.4 GHz和5 GHz無線局域網(wǎng)的比較

　　2.45和5 GHz無線局域網(wǎng)（WLAN）廣泛應用于消費電子應用。然而，對于工業(yè)和更多的關(guān)鍵任務(wù)的應用程序，有性能和干擾的要求和特點，需要認真考慮，然后選擇使用哪個頻段。

　　這篇文章將解釋2.45和5 GHz WLAN操作之間的主要差異，在突出使用5 GHz的無線局域網(wǎng)與2.45 GHz系統(tǒng)相比設(shè)計工業(yè)無線設(shè)備的優(yōu)勢。本文將5 GHz工業(yè)應用提出了一些最近發(fā)布的IEEE 802.11x模塊和設(shè)計工具，以及實用的設(shè)計技巧。

　　Comparing 2.45 GHz and 5 GHz

　　The license-free 2.45 GHz Industrial， Scientific and Medical （ISM） band is particularly popular for consumer and industrial WLANs. Wi-Fi， based on 2.45 GHz IEEE 802.11x technology， for example， is well established for domestic wireless applications because it offers the range， bandwidth and wall-penetrating properties required for today’s mobile consumer electronics applications.

　　But 2.45 GHz Wi-Fi does have its drawbacks， notably limited provision for avoiding interference from close by Wi-Fi installations and numerous other 2.45 GHz protocols. For example， Bluetooth， ZigBee and proprietary applications such as cordless phones.