SBIR Phase II: Spiral Polynomial Division Multiplexing

The broader impact/commercial potential of this project is that it addresses the bandwidth crisis, the problem of transmitting an exponentially growing amount of data through a fixed amount of increasingly congested spectrum. The bandwidth crisis limits economic growth by constraining communication, and also poses very serious challenges for national defense and disaster response. Making better use of limited spectrum is therefore of high societal and commercial importance. This project will study a new approach, called spiral modulation, for achieving much more spectrally efficient communication than previously thought possible and thereby directly addressing the bandwidth crisis. Commercially, this could facilitate much more rapid data transfer, enhancing existing business applications and enabling new ones. Spiral modulation is applicable to any form of electromagnetic communication, whether wireless or wire-based. It could lead to commercialization across a wide range of communication sectors including but not limited to wireless, mobile internet, unmanned vehicles, automotive, aviation, and Internet of Things. It is a dual use technology with both civilian and defense applications. Ultimately, spiral modulation could become the core technology for the worldwide telecommunications industry. This Small Business Innovation Research (SBIR) Phase II project applies new mathematics to the problem of encoding information into waveforms for telecommunication. In current digital communication, information is transmitted using symbol waveforms constructed from sinusoids which have constant amplitude over each symbol period. This approach is known to produce a sharp upper bound on the highest spectral efficiency that can be achieved. By instead constructing symbol waveforms from sinusoidal waveforms with continuously-varying amplitude, spiral modulation bypasses the theoretical limitation on spectral efficiency. Building on prior Phase I research, this project will build an end-to-end hardware prototype to establish the implementation path and performance characteristics of spiral modulation. The research will progress in stages from waveform design and spectral efficiency measurement experiments, through end-to-end radio design in software, the hardware prototype development and documentation of best practices. It is anticipated that this research will show significant spectral efficiency advantages over existing signal modulation techniques. Other possible advantages for spiral modulation may also appear, such as greater tolerance for interference and phase distortion.