In-Band Controllable Radio Interference Generation for Wireless Sensor Networks

Interference signals negatively impact the performance of wireless embedded systems. The increased packet losses, delays and energy consumption experienced by devices operating in environments subject to interference is particularly critical in constrained systems, like wireless sensor networks. The need to design and test systems for mitigating the effects of interference prompts for the capability of reproducing in a controllable way suitable interference signals. Solutions have recently been proposed that tackle the problem by making use of 802.15.4 compliant radio transceivers, like those available on board of commonly used sensor nodes, thus paving the way for low cost and repeatable generation of interference which could reliably emulate real-world scenarios, for instance densely deployed networks. In this article we present an investigation regarding the emulation of interference sources by means of 802.15.4 radios on novel 32 bit wireless system-on-chip. The study is based on extensive experimental evaluation, providing novel insights on the main features of the system. In particular, the effects of interference on the communication link, measured in terms of packet reception rate, are investigated for different parameters (namely, duty cycle and power of the interference signal, communication protocols, and payload size) and results are discussed concerning the feasibility of emulating background noise by means of the analysed techniques.