Design of multi-interface Wi-Fi node for Sensor Network

In this paper, a multi-interface Wi-Fi node for Wireless Sensor Network (WSN) is constructed. Wi-Fi is connected through SPI (Serial Peripheral Interface Bus) to form the relatively energy saving wireless transmission. Along with other interfaces, the multi-interface function requirements are satisfied. Firstly, the overall module design framework is introduced, followed by the hardware and software designs respectively. This project focuses on the node expansibility, taking TQ2440 as the base hardware platform, which is rich in interfaces with reserved extensive area. On the other hand, eCos is adopted to provide the real-time performance. After the drivers' implementation on eCos, which contain serial, flash, Ethernet and Wi-Fi, OLSR route protocol is ported to eCos as system route used in the data transmission course. Ultimately, nodes are deployed in AdHoc mode network for tests, which prove that the wireless data acquisition and transmission are available for the node construction. Meanwhile, the AdHoc mode can enhance the robustness of the network, reducing the network failure due to the router crashing in the central control network. It is believed that the node design realizes a prototype which can be used in most of the remote monitoring scene of WSNs.