COLiDeR

In this work, we present COLiDeR, the first practical system for two-path relaying using off-the-shelf half-duplex radios. While two-path relaying has been mostly studied from a theoretical perspective in the literature, our solution addresses the challenges of making it practical by introducing two key contributions. First, using a measurement-driven approach, we identify the best approach for a radio to handle two overlapping signals. Just as important, we carefully quantify its limits and introduce the concept of the decoding areas. Second, we introduce a cross-layer protocol that seamlessly navigates the decoding areas with the objective of maximizing throughput while minimizing decoding failures. Experiments on a 4-USRP testbed show that COLiDeR delivers between 80-95% of the relaying performance of an ideal full-duplex radio while incurring negligible decoding failures.