SBIR Phase II: 3D Photonic Filters for Full Duplex, Interference Free Network Links

The broader impact/commercial potential of this project include the ability to meet the requirements of cable infrastructure while opening additional markets in spectrum allocation by solving key technical problems. There is a massive need for improved connectivity for both fixed and mobile applications, in both urban and rural communities, within the nation. Wired infrastructure has struggled to keep up with the needs of users due to the large capital involved in deploying fiber to communities. Additionally, new applications like Internet of Things (IoT) and autonomous vehicles are entirely reliant on wireless technologies. Mobile data usage has been experiencing exponential growth, 92% CAGR from 2006-2016. Current mobile infrastructure cannot support next generation applications like remote healthcare, vehicle-to-vehicle and vehicle-to-infrastructure communication for self-driving vehicles and next generation connected farming. These applications are constrained by the available bandwidth, low reliability and high latency of today's mobile networks. The industry is looking to expand reach and capacity of existing infrastructure to enable these applications with the potential to drastically communication. This Small Business Innovation Research Phase II project will build upon the existing low-loss photonic integrated circuit (PIC) Finite Impulse Response (FIR) filter technology developed under Phase I by demonstrating a commercially viable three-dimensional (3D) PIC filter and canceler. The intellectual merit centers around the 3D PIC architecture with fast layer switching and ultra-low-loss waveguides for creating highly adaptable, tunable true time delays and detailed characterization of interfering signals in complex, dynamic multi-path reflection environments in cable and wireless solutions. The 3D PIC system aims to achieve under this project: total interference cancellation of >100 dB; small die footprint for a multi-tap cancellation FIR filter; high-speed switching; demonstration of full duplex communication links; and demonstration of band leakage and PIM interference cancellation in a laboratory environment. The improved designs will allow targeting additional markets in wireless communication involving complex interference cancellation scenarios that today severely limit spectrum utilization and network throughput. The proposed 3D PICs not only enable full duplex operation (co-channel self-interference) but also adjacent channel cancellation (guard band elimination) and passive intermodulation distortion (PIM) cancellation for higher throughput backhaul. 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.