Audio-Jack Based Communication Interface Of Mobile Terminal And Sensor Node

As the rapid development of the intelligent mobile terminal, a growing number of smart mobile terminal platform is constantly emerging, and sought after by the majority of users. At the same time, wireless sensor networks, along with the development of computer technology and microelectronics technology, is also flourishing and taking the international’s attention. The communication between mobile terminals and wireless sensor networks is generally that the collected node for wireless sensor networks is sent the date to the management node and the mobile terminal through the Internet to access the data.However, wireless sensor networks will become the largest network after the Internet. Therefore, the mobile terminal can be more convenient access to the sensor network and it will greatly enhanced smart function of mobile terminals.The paper designs and implements a headset based communication interface of intelligent mobile terminal and wireless sensor node, and makes mobile terminals more convenient to communicate with the wireless sensor nodes. Since the headphone jack exists widely in the mobile terminals, and therefore this interface which bases on the headphones, has a good versatility, operating system based on the same hardware platform, can use the same interface driver and facilitate the secondary development based on this interface.Two ways of communications of intelligent terminals and wireless sensor nodes are designed. The first way is that single byte transfer mode which based on the the UART protocol. And the second way is indefinite long-buffered data transfer mode. The second buffer data transmission has better flexibility, and there are obvious advantages in the maximum transmission rate than the first way. When the baud rate is at1378bit/s and the length of the packet is512bits, the maximum effective transfer rate of the buffered data transmission mode is up to1355bit/s and the bandwidth occupancy rate is over98%.This paper describes how to develop the driver based on TinyOS wireless sensor network operating system, as well as the intelligent terminal driver based on Windows Phone7and iOS operating system. At the same time. And the communication performance of the interface is tested, as well as the development’s flexibility.