Fine-Grained Frequencies Meet Synchronous Transmission

<div>Fine-grained frequencies have been used in several recent works to enhance network throughput as well as combat Cross Technology Interference (CTI) issues in licence free ISM bands. We observe that synchronous communication based strategies, due to the scope of inter-frequency capture-effect, are inherently more capable of supporting in-parallel communication over multiple channels even when the Center Frequency Distance (CFD) of the channels are very low (<5 MHz). In this work, we pursue an in-depth study of how fine-grained frequencies can be used in conjunction with synchronous communication to extract the maximum benefit from a very narrow band of available frequencies (e.g., 2- 5 MHz) for in-parallel intra-group communication. In this direction, we propose a simple and efficient group formation strategy to automatically define groups in a given WSN/IoT network to boost up in-parallel intra-group communication efficiency. Through extensive experimental evaluations in existing WSN/IoT testbeds, we show that in-parallel one-to-all dissemination in the groups formed through the proposed strategy can execute with upto 73% higher reliability while consuming upto 41% lower energy as compared to the same running among the groups formed through naive strategy with only 4 consecutive frequencies separated by 1 MHz and upto 20 groups.</div>