Wireless Input Devices and Their Communication Module for Wearable Computers
Recently, many researches about wearable computers have been performed because they can be used to aid inspection, medical, navigation, communication, and cognitive tasks (Brugge & Bennington, 1996. Siegel & Bauer, 1997. Abowd et. al., 1997). Workers can perform more tasks using wearable computers (Greene & Fiske, 1999. Sawhney & Schmandt, 1997. Ross, 2001). Since most input and output devices in wearable computers are connected to the CPU board through wires, these wires do not allow us to put each input device arbitrary location away from the CPU board in a wearable computer. As more input devices are added, the CPU board becomes larger in order to have their corresponding connectors. Furthermore, a wearable computer should be turned off when some input device is being connected or disconnected to the CPU board. Existing wireless input devices to avoid these problems are IR (infra red) and Bluetooth input devices. But, an IR input device has short operational distance and limited direction. Though the performance of a Bluetooth input device is much better than that of an IR input device, the Bluetooth input device is hard to implement and its cost is very high compared with that of an IR input device. Thus, low cost wireless input devices that also have good performance are needed. In this paper, wireless input devices and their communication module using RF (radio frequency) modules are proposed and implemented for this purpose. In section 2, the proposed devices and communication module are described. Also their communication scheme is described. In section 3, wireless mouse, wireless keyboard, and one communication module are implemented. Section 4 describes the conclusion.