SBIR Phase II: Simultaneous Transmit-Receive and Full-Duplex Millimeter-Wave Massive Multiple-Input and Multiple-Output Systems

The broader/commercial impact of this Small Business Innovation Research (SBIR) Phase II project is to enable faster, lower-cost deployment of high-capacity wireless infrastructure in locations where fiber is impractical, slow to deploy, or cost-prohibitive. The project advances a wireless transport platform capable of substantially improving bandwidth and reducing latency without requiring additional spectrum. If successful, this technology could improve connectivity for distributed artificial intelligence systems, industrial facilities, critical infrastructure, public safety networks, and defense applications. By increasing the effective capacity of existing spectrum resources, the project supports more efficient use of national communications assets. The innovation also advances scientific understanding of full-duplex (simultaneous two-way) millimeter-wave communications, adaptive beamforming, and the integration of machine learning into physical-layer wireless systems, contributing to future developments in advanced wireless infrastructure. This Small Business Innovation Research (SBIR) Phase II project addresses the technical challenge of enabling simultaneous transmit and receive on the same frequency band at millimeter-wave frequencies, a capability that is limited by self-interference between transmit and receive paths. The research objective is to design, fabricate, and demonstrate an integrated full-duplex massive multiple-input multiple-output wireless transport system that achieves high levels of self-interference suppression while maintaining signal fidelity and spectral efficiency. The proposed work combines multi-stage self-interference cancellation in the radio frequency, analog, and digital domains with adaptive beamforming and machine learning-based optimization. The project will deliver a prototype capable of multi-gigabit, real-time packet transport over multi-kilometer distances and will validate performance through quantitative measurements of cancellation depth, error vector magnitude, and throughput improvement relative to conventional time-division duplex systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.