Content Dependent Bandwidth Enhancement

Project Pika addresses the challenge of receiving messages on a radio channel when multiple users inadvertently collide on the channelan event that is especially likely during times of disaster or emergency. In Phase I we demonstrated the feasibility of this signal source separation through analysis and simulation for a subset of communication modes under the assumption of certain constraints. In Phase II, we relax these constraints and generalize the capability for more communication waveforms and signal sources, and develop a prototype communication system demonstrating the capability in open air tests through real world propagation. Of particular emphasis is the underdetermined case, where there are more signals in a received mixture than available receiver channels. The project will result in receiver software that is portable to modern software defined radio systems, and that is compatible with current hardware and legacy waveforms.