優(yōu)化ZigBee無線電性能和能源使用的技巧

　　ZigBee收發(fā)器是一種流行的，在某些情況下，不可或缺的元素，現(xiàn)代能源管理和樓宇自動化系統(tǒng)（圖1）。然而，并非所有的ZigBee系統(tǒng)都是平等的，它們的性能和電池壽命的差異可能意味著產(chǎn)品的成功或失敗。電源/性能優(yōu)化設計需要仔細選擇主機系統(tǒng)和無線電系統(tǒng)組件，但即使是最好的參考設計也需要工程師的觸摸來對特定應用程序進行微調(diào)。正如我們不久將看到的，設計問題，如無線電功率管理、天線分集、出站數(shù)據(jù)和入站數(shù)據(jù)的智能管理，以及對系統(tǒng)休眠模式的仔細關注，都在設計健壯、長壽命的能量管理設備中起到了作用。

　　Figure 1： ZigBee wireless technology’s robust， low-power characteristics have won it wide acceptance in environmental monitoring， energy management， lighting control， and building automation applications.

　　Design for performance

　　Although all commercially-available ZigBee transceivers are compliant with the standard’s simple， well-defined air interface， a system’s actual performance （i.e. how closely it matches the data rate， range， and resistance to interference of a so-called ideal system） is still dependent on the designer’s skills. Many issues involve the radio subsystem， including receiver sensitivity， transmit power， and its ability to cope with the interference， fading， and multipath conditions found in most real-world environments. These factors affect a system’s range， data rate， and how much of its theoretical capacity is consumed by dropped packets or other transmission errors. Any re-transmission of lost or garbled packets impacts the overall performance and efficiency of the communication network in terms of latency， power consumption， and increased radio activity that creates additional channel interference.