问答题 Bluetooth is the newest kid on the technology block, and it holds a lot of promise for the assistive technology industry. Named for a 10th Century King of Denmark who unified the kingdoms of Denmark and Norway, Bluetooth is a short-range wireless communication specification that promises to improve and increase electronic access to a number of environments by overcoming some of the obstacles typical of current technology. Bluetooth technology will enable devices to communicate and transfer data wirelessly and without the line-of-site issues of infrared technology.
So how does it work."?
Bluetooth devices search each other out within their given operational range. Unlike devices that are wired together, Bluetooth devices do not have to be aware of the capabilities or properties of the devices to which they will connect beforehand. Bluetooth devices have a built-in mechanism that lets each device identify itself as well as its capabilities as it connects into this new Bluetooth network. This dynamic network does have a controlling device that designates itself as the master for the connection. Its programming and the capabilities necessary for the given task determine whether or not a device can be a master. For example, a cell phone may act as a master device when connecting to a headset, an ATM, or an information kiosk. However, the same cell phone or headset may act as a slave device to the information kiosk, now acting as the master device, broadcasting emergency evacuation information. The cell phone and kiosk can function in either capacity depending on the required function and their programming.
【正确答案】
【答案解析】“蓝牙”作为技术家族的新生儿,为辅助性技术作业带来了不少希望。“蓝牙”得名于10世纪一位统一丹麦和挪威王国的丹麦国王,是一种短程无线通信技术规范。它能逾越当前技术中的某些典型障碍,有望改善并增强各种环境中的电子通信能力。蓝牙技术能使设备进行无线通信和数据传输,并且不受红外技术直线对传的限制。
那么蓝牙是如何工作的呢?
蓝牙设备在特定的操作范围内相互搜索。和接线设备不同,蓝牙设备无须事先知道待联设备的性能或属性。蓝牙设备的内置装制可以使每种设备在接入新的蓝牙网络时识别自己的身份和性能。这种动态网络的控制设备可以将自己指定为联网的主设备。它的编程能力和完成特定任务所需的能力决定其能否成为主设备。例如,一部手机如果连上耳机、自动取款机或问讯台,可以作为主设备。但问讯台如果作为广播紧急疏散信息的主设备,那么同样的手机或耳机就成了从设备。手机和问讯台可以按照所需的功能和编程能力用作主设备或从设备。