Proof-of-concept implementation for network orchestrated relay selection mechanism

This paper describes a small-scale software radio proof-of-concept implementation developed to investigate a network orchestrated relay selection concept. The idea aims to reduce "energy-in-the-air" by replacing single long transmissions with multiple short ones via a relaying node when possible. The implementation includes mechanisms for real-time over-the-air packet transmissions for both control and user-data traffic, and on-the-fly network topology reconfiguration, which we utilized to enable the concept. We show that significant benefits were reaped from this real-world implementation despite the relatively simplistic scenario emulated by our indoor laboratory setup. Apart from the obvious advantages of testing the concept over a real wireless medium with its associated physical characteristics, other unforeseen factors were also uncovered. Asymmetries in radio channels, variations in supposedly identical node hardware, and timing issues affecting the proposed algorithm, were just some of the experiences encountered and fed back into the design process which resulted in significant refinements and improvements to the concept. The experience shows our research-via-experimentation approach with small-scale software radio yields benefits in meeting new challenges in wireless communications.