AARC: Cross-layer wireless rate control driven by fine-grained channel assessment

This paper proposes a wireless channel assessment metric A posteriori Bit Error Probability (ABEP) that indicates the error likelihood of each bit during demodulation. Estimated upon constellations, ABEP provides the finest granularity (per bit) in revealing dynamic channel conditions. With comparative validation on an implemented GNU SDR testbed, ABEP significantly outperforms a pioneer flagship work SoftPHY in fidelity and channel predictability. An ABEP based channel assessment algorithm is devised to recognize channel conditions such as channel fading and collision, and it demonstrates a recognition accuracy up to 99% across various channel conditions. Based on the ABEP channel assessment, a cross-layer protocol-ABEP-enabled adaptive rate control (AARC)-is designed for high wireless network performance. AARC is implemented and evaluated on ns-3 simulator with a newly developed physical layer. Extensive experiments show that AARC significantly outperforms prior rate control solutions in rate selection accuracy and throughput.