OBJECTIVE: This research seeks novel algorithms and signal processing techniques that will minimize Aegis-to-3G&4G and 3G&4G-to Aegis interference. Space-time, adaptive and other approaches are sought for broadest utility and generality. DESCRIPTION: The Missile Defense Agency (MDA) is seeking the development of novel RF modulation, timing and phasing as well as orthogonal and bi-static arrangements to increase Aegis BMD compatibility with evolving civilian 3G and 4G communication systems worldwide. This effort should include the development of advanced algorithms and enhanced signal processing techniques to increase the Aegis BMD coexistence margin with these civilian networks. Preferably these novel RF changes, advanced algorithms and enhanced signal processing techniques should be implemented with no changes to the Aegis BMD radar and signal processing hardware. Global mobile communication network carrier bands are beginning to encroach on operational US Government Civil and DOD weather and fire control radars, including the AN/SPY-1, X-band radar used by Aegis BMD. Straightforward geometric and aperture techniques solve the plurality of interference challenges. However, it is desired to further develop, implement, verify and field both novel RF waveforms and advanced signal processing algorithms that can modify Aegis transmit and receive operations to come as close to non-interaction with these networks as possible. The initial effort should involve the investigation via calculations and experiments of new RF waveform characteristics that could enhance Aegis BMD coexistence with civilian 3G and 4G communication networks. This should also include the development of associated signal processing algorithms. The effort should also include the development of new advanced signal processing techniques for use on existing SPY-1 RF waveforms in order to enhance the desired coexistence margin. Finally, the effectiveness of any new RF waveform characteristics and signal processing techniques should be demonstrated via unclassified modeling and simulation. PHASE I: Perform an investigation and research of new RF waveform characteristics that could enhance Aegis BMD coexistence with civilian 3G and 4G communication networks. Design innovative RF techniques (i.e. modulation, timing and phasing) that can help increase AN/SPY-1 S-band radar compatibility with civilian 3G and 4G communication networks. These new RF waveforms must be largely compatible with the existing AN/SPY-1 S-band radar. Include the associated processing algorithms that will support the new RF waveforms. The output of the Phase I shall be a proof of concept design/study; identify designs/models and test capabilities, and conduct a feasibility assessment for the proposed model, technique, and/or methods. Phase I work should clearly validate the viability of the proposed solution. Phase I should also result in a clear concept of operations document. PHASE II: Based on the results and findings of Phase I, refine the RF changes, and increase the capabilities of the advanced algorithms and enhanced signal processing techniques. Then demonstrate their effectiveness using operational SPY-1 radar in RF environments shared with various 3G and 4G networks used worldwide. Develop an unclassified model showing the effectiveness of these RF waveform changes, advanced algorithms and enhanced signal processing techniques to increase the SPY-1 Radar coexistence margin with these networks. The Phase II objective will be to validate a new technology solution that MDA users and prime contractors can transition in phase III. Validate the feasibility of the Phase I concept by development and demonstrations that will be tested to ensure performance objectives are met. Validation would include, but not be limited to, system simulations, operation in test-beds, or operation in a demonstration subsystem. The goal of the Phase II effort is to demonstrate technology solution viability. PHASE III: In this phase, the contractor will apply the innovations demonstrated in the first two phases to one or more MDA systems, subsystems, or components. The objective of Phase III is to demonstrate the scalability of the developed technology, transition the component technology to the MDA system integrator or payload contractor, mature it for operational insertion, and demonstrate the technology in an operational level environment. COMMERCIALIZATION: The contractor will pursue commercialization of the various technologies and models developed in Phase II for potential commercial uses in such diverse fields as air traffic control, weather systems, and other tracking applications.