  This paper develops a theoretical framework for enabling seamless transfer of
digital information from classical microwave domain to the quantum optical
domain in wireless-to-optical converters. A quantum mechanical network model is
introduced to characterize microwave-to-optical digital information mapping in
antenna-coupled electro-optic modulator-based converters. Design guidelines are
discussed to maximize the information mapping strength. The derived model is
then extended to show phase-space encoding of optical coherent-states with
classical wireless microwave constellation. Further, the challenge of
inter-symbol overlap in the encoded quantum optical phase-space due to
quadrature fluctuations is highlighted. The possibility of erroneous
phase-space encoding due to quadrature fluctuations is pointed out, followed by
a potential mitigation technique. The presented framework also lays the
groundwork for encoding other non-classical states of light such as squeezed
states, and hence forms the basis for bridging classical microwave and quantum
optical links in the near future.
