Michael Bryant (Committee Member), Robert Penno (Committee Member), Kuldip Rattan (Committee Chair), Michael Wicks (Committee Member), Zhiqiang Wu (Committee Co-Chair), Xiadong Zhang (Committee Member)
Doctor of Philosophy (PhD)
As electromagnetic spectrum availability shrinks, there is growing interest in combining multiple functions, such as radar and communications signals, into a single multipurpose waveform. Historically mixed-modulation has used orthogonal separation of different message signals in different dimensions such as time or frequency. This research explores an alternative approach of implementing an in-band, mixed-modulated waveform that combines surveillance radar and navigation functions into a single signal and demonstrates the feasibility of this approach for a limited area navigation solution. The first contribution of this research is the use of reduced phase-angle binary phase shift keying (BPSK) along with overlapped (channelized) spread-spectrum phase discretes based on pseudorandom noise sequences to encode multiple messages in a single pulse. The goal is to determine if these signals can achieve satisfactory message performance in a radar pulse while minimizing the effect on radar performance. For the purpose of this research, radar performance will be evaluated in terms of power spectral density, matched filter auto-correlation for target detection, and the ambiguity function. The second contribution is the development of an algorithm that permits the use of received navigation messages with non-synchronous times of arrival. Numerical simulations of the resulting iterative, non-synchronous geolocation algorithm demonstrate rapid convergence of the estimated and true trajectory despite large temporal differences in message time of arrival.
Department or Program
Ph.D. in Engineering
Year Degree Awarded
Copyright 2016, all rights reserved. My ETD will be available under the "Fair Use" terms of copyright law.