SBIR Phase II: Physical (PHY) Layer Rateless Codec Technology for Proximity Space Links

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) project stems from developing a revolutionary wireless communications technology innovation based on physical (PHY) layer rateless codes which could provide high throughput and high coverage with low computational costs, minimum latency, and enhanced energy efficiency, i.e., long battery life. The initial target market is the space communications market, both commercial and government space programs. The Phase II project focuses on enabling technology addressing real capability gaps that could provide cheaper and faster solutions for the data communication systems of commercial and government space customers. The first testing ground for the novel PHY layer rateless codec technology will be the satellite and ground communications systems (gateways/terminals) of the PWSA - Proliferated Warfighter Space Architecture. In the commercial sector, well known companies are launching Low Earth Orbit (LEO) and Very Low Earth Orbit (VLEO) constellation of satellites for broadband connectivity in underserved and remote areas of the world. Both the satellite and consumer terminal of the mega satellite constellation systems can be equipped with novel modem solutions. The novel satellite modem will be on the supply chain of Satellite Vendors and Satellite Operators in the LEO market. Commercial customer end users include Airlines, Maritime vehicles, Mobile Network Operators for 5G connectivity and Cellular Backhaul, and Residential Internet Access. This SBIR Phase II project proposes to develop a Physical (PHY) rateless codes based novel link adaptation transmission technology for the reliable transmission of information bits between a wireless transmitter and receiver. PHY rateless codes have the innate ability to adapt both the code construction and the number of code bits for an as-need basis incremental transmission of code bits. The constituent code of link adaptation technology in the PHY layer works with the Automatic Repeat Request (ARQ) protocols in the data link layer. The Phase II project designs innovations for the component encoders and decoders of the PHY layer rateless codes such as designing a GRAND (Guessing Random Additive Noise Decoding) decoder for the LT codes, investigating the variable node degree design for the tradeoff between waterfall and error floor performance, pairing probabilistic amplitude shaping with PHY layer rateless codes and concatenation with CRC for maximizing the minimum Hamming distance for short block length performance. New design features based on deep learning/AI enhancements, structured permutations, and techniques for optimizing the LT code degree distributions will be added to the PHY rateless encoder and decoder. The expected technical results include patented designs for encoder, decoder, and the related software in Matlab/Python for the blocks of a `FutureG’ baseband modem. 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.