Transmit beampattern design is critically important in many applications including defense and homeland security applications as well as biomedical applications. Traditional array approaches require all antennas to transmit the same waveform and the power and phase of each antenna output are adjusted to achieve a desired transmit beampattern. However, in many practical systems, the antenna output powers are constrained, and adjusting only the phase of each antenna output poses significant limitations in transmit beampattern designs.
This research addresses the underlying transmit beampattern design technical issues associated with the current limitations. Specifically, the investigators exploit waveform diversity, i.e., the diversity offered by different sensors in a distributed-sensor system transmitting different but correlated or uncorrelated waveforms, to achieve flexible transmit beampattern designs. Waveform diversity offers a new paradigm for flexible beampattern design because of significantly increased degrees of freedom. The investigators focus on the following three application areas: 1) improved passenger aircraft protections by rending shoulder-launched guided missiles ineffective via effective directed energy systems, 2) enhanced breast cancer therapies by providing a sufficiently large focal spot using an ultrasound array under elemental power constraints, and 3) making the ocean quieter by introducing, as viable alternatives to existing systems, distributed sensor networks with each sensor output power limited to ensure the safety of the whales and other ocean creatures.
Level of Effort Statement At the recommended level of support, the PI and Co-PIs will make every attempt to meet the original scope and level of effort of the project.
