VoIP over IEEE 802.11 wireless networks: Experimental analysis of interference effects

The interference effects on voice over Internet protocol (VoIP) applications over wireless local area networks (WLANs) are here dealt with. In particular, attention is paid to the IEEE 802.11 g standard, with Bluetooth signals, additive white Gaussian noise (AWGN) and competitive data traffic acting as interferer. The analysis is conducted experimentally following a cross-layer approach and through the deployment of a proper testbed within a semi-anechoic chamber. The purpose is to investigate on the effects of some common types of interference on a WLAN supporting VoIP applications, and to deduce from the experiments valuable hints for improving the setup of a WLAN in the presence of interference. Cross-layer measurements are performed at network/transport, physical and application layer.