了解使用ZigBee的無線照明控制的好處

　　介紹和產品重點

　　商業樓宇照明控制設備市場預計將從2010增加到2017倍，IMS研究項目年出貨量將達到6160萬臺。為了滿足日益嚴格的能源立法，降低能源消耗是推動這一增長的最大動力之一，美國能源部認識到，照明占商業大廈能源使用量的25.5%。雖然美國可能會通過能源立法和相關的刺激方案來安裝照明控制，但歐洲和其他國家的其他國家正在看到這樣的系統的吸收，因為建筑業主試圖減少他們自己的消費。

　　目前安裝的照明控制系統使用有線和無線連接。無線通信中，使用最廣泛的技術是802.15.4標準，它定義了一個低速率無線個人區域網（LR-WPAN）也是ZigBee通信協議的基礎上?。到目前為止，很多系統已經部署了專有的協議，但越來越多的公司，如樓宇自動化公司Daintree的網絡和關鍵照明供應商飛利浦照明系統，采用標準的解決方案，如ZigBee?促進互操作性的需要。

　　本文將探討ZigBee的好處和它的網狀拓撲結構作為無線技術的選擇照明控制。更具體地說，它將從領先的供應商看一些?ZigBee收發器解決方案；對芯片的em351系統從Silicon Labs，Jennic jn5148-001模塊恩智浦和單獨的無線電和單片機解決方案從愛特梅爾（at86rf231和ATmega2560）；看到這些有助于更廣泛的生態系統。

　　Understanding the standards

　　The word ZigBee? is rapidly becoming another of those brand names like Hoover， Sellotape， and even Google that have become nouns and verbs， referring to generic products and actions; respectively a vacuum cleaner， clear adhesive tape， and searching the Internet. ZigBee? of course comes from the ZigBee? Alliance， a non-profit association formed in 2002 to provide open wireless networking standards focused on monitoring， control and sensor applications. The Alliance’s activities are very much determined by its members， which come from all around the world and include large and small companies， public bodies / government agencies， universities， and other interested parties. Consequently， a number of standards have been formulated to address the needs of specific markets and applications such as： ZigBee? Building Automation， ZigBee? Remote Control and more recently ZigBee? Light Link， a standard designed to provide LED lighting controls for consumer products.

　　The prime purpose of the ZigBee? standards is to provide equipment manufacturers with an open-source specification that enables them to develop interoperable products. As such， it is essential to understand what the standards cover and， just as importantly， what they do not cover. Networking， whether wired or wireless， is mostly based on the OSI model， which defines seven layers from the physical layer through to the application layer. ZigBee? defines networking protocols that operate from layer 3 upwards but does not define layers 1 and 2. Instead， it relies on 802.15.4， one of the IEEE’s 802.15 groups of standards for wireless personal area networks （WPAN）， to do this. This is often a source of confusion as devices that solely implement 802.15.4 may be referred to as ZigBee? transceivers when strictly they are not implementing any specific ZigBee? function， and are probably just as applicable to other low data rate WPAN applications supported by 802.15.4.