定义了WMAN的PHY及MAC层标准的标准是（）。
- A.IEEE802.11
- B.IEEE802.15
- C.IEEE802.16
- D.IEEE802.20
正确答案及解析
正确答案
解析
IEEE 802委员会于1999年成立了802.16工作组来专门开发宽带无线接入标准。IEEE 802.16负责为宽带无线接入的无线接口及其相关功能制定标准，它由三个小工作组组成，每个小工作组分别负责不同的方面：IEEE802.16.1负责制定频率为10～60GHz的无线接口标准； IEEE 802.16.2负责制定宽带无线接入系统共存方面的标准；IEEE 802.16.3 负责制定频率范围在2～10GHz 间获得频率使用许可的应用的无线接口标准。I E E E802.16标准所关心的是用户的收发机同基站收发机之间的无线接口，包PHY MAC的规范。
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