Validation for 802.11b Wireless Channel Measurements

Few researchers have undertook the task of measuring the wireless channel at the frame level to understand performance issues related to frame loss and signal strength. This paper proposes a measurement procedure for terrestrial wireless networks based on cheap hardware and custom software, and validates it through experiments on real-word wireless environment. In order to validate the measurement procedure, we carry out a comprehensive measurement campaign in a rural environment and we evaluate statistics about frame loss and signal level in the IEEE 802.11b wireless channel. Frames are transmitted and received by using two cheap laptops with standard Linux drivers and purposely written software. A first validation step compares the behaviour of the received signal power level with the two-ray propagation model. A subsequent step compares the observed frame loss with the expected coding gain at various transmission rates. Graphs of the observed frame loss rate at different transmission rates are provided for a rural environment, where the two-ray propagation model is a good fit.