By Carmo, J.P.; Correia, J.H.
Handbook of Research on Mobility and Computing: Evolving Technologies and Ubiquitous Impacts
This chapter presents a low cost/fast prototyping wireless sensors network that was designed for a huge range of applications and making use of low cost commercial of the shelf components. Such applications includes industrial measurements, biomedical, domestic monitoring, remote sensing, among others. The concept of the wireless sensor network is presented and simultaneously, hot topics and their implementation are discussed. Such topics are valuable tools and can't be discarded when a wireless sensors network is planed. By the contrary, such tools must be taken in account to make the communications between the nodes and the base station the best possible reliable. The architecture, protocols and the reasons that were behind the selection of the components are also discussed. The chapter also presents performance metrics that are related to with the physical characteristics of sensors and with the radio specificity. Microcontrollers with a RISC architecture are used by the network nodes to control the communication and the data acquisition and operate in the 433 MHz ISM band with ASK modulation. Also, in order to improve the communication and to minimise the lost of data, it is predicted to put the wireless nodes to handle line and source coding schemes. This chapter cover the following topics: - the focus and application of the wireless sensor network; - the implications of the radio system; - the test bed implementation of the proposed low cost wireless sensors networks; - the wireless link power budget, coding and data recovering; - performance metrics of the wireless sensors networks; - cost analysis versus other technologies (wired and emerging wireless).