Research On PC Information Easy Input System Based On Bluetooth Technology

With the development of science and technology,electronic products such as smart-phones and PCs are gradually popularized.PCs' information input devices are very important for human-computer interaction equipments.Traditional information input devices such as mouse and keyboard use wired communication,but it is complicated and brings a lot of inconvenience.Wireless mouse and keyboard can effectively make up for these shortcomings,but they have issues such as expensive,high power consumption,poor portability.In order to solve these problems,we realized a kind of information easy input system for Personal computers based on Bluetooth technology on the smart phone.The function of the mouse and keyboard has been integrated into the smart phone,which realizing the information easy input.In the end,we produced a prototype.The system requires only a single USB Bluetooth adapter as a secondary device compared to existing devices on the market.Based on the basic principle,this paper elaborates the basic principles of Bluetooth 4.0 BLE protocol,USB HID protocol and impedance matching.On this basis,completed the USB Bluetooth adapter hardware circuit design.Using TI CC2540 Bluetooth radio transceiver chip as the master chip,given the chip's peripheral circuit design.For Bluetooth RF circuits,using MIFA antenna.Using HFSS software to simulate the antenna and analyze the radiation characteristics,the theoretical value of the input impedance of the antenna is obtained.The impedance matching circuit is designed by Smith software.Use App CAD to determine the RF microstrip trace width of 1.808 mm.Altium Designer used to draw the schematic,Layout layout,and completed the production of circuit boards and antenna testing.The smart-phone side calls the Android Bluetooth API to search and connect the BLE device and communicate with the USB Bluetooth adapter according to the Bluetooth 4.0 BLE protocol.Based on the OSAL operating system,the USB Bluetooth adapter uses C language to communicate with smart-phones and PCs according to Bluetooth 4.0 BLE protocol and USB HID protocol respectively.Based on the system hardware and software implementation,the system test was carried out.The test results show that the system can realize the quick input of PC's information.The system is the most stable communication within 9 m.The farthest communication distance can reach 15 m.