This paper forms the basis for wireless constellation detection in seamless digital wireless-photonic receivers. The two intermediary stages in the proposed receiver model are discussed: Wireless-to-Optical (W-O) and Optical-to-Electrical (O-E) symbol mapping stages. The inherent barrier of erroneous constellation detection due to symbol degeneracy in the W-O and O-E mapping stages is reported. A receiver architecture with optical phase diversity is subsequently proposed to overcome the barrier of degeneracy. Breaking degeneracy not only lays the foundation for reliable detection of wireless constellations in seamless digital wireless-photonic receivers, but also ensures their compatibility with practical modulation schemes such as M-PSK and M-QAM.

In this paper, we show that seamless wireless-to-optical constellation-mapping is inherently governed by the direction of wireless reception. This lays the foundation for seamless electro-optic beamforming in wireless-over-optical links. We show that seamless electro-optic beamforming is governed by (i) direction-dependent electro-optic array-factor of the beamformer, and (ii) direction-dependent effective wireless constellation-rotation. The analytical conditions and design equations for enhancing the spatial selectivity of electro-optic beamformers  are discussed in detail. The inadvertent nature of secondary maximas of the electro-optic array-factor is pointed out. We also highlight the impact of effective wireless constellation-rotation on seamless constellation-mapping. Further, we propose a seamless electro-optic beamforming configuration that enables wireless-spatial to optical-wavelength division multiplexing. The theoretical contributions presented in this paper are crucial for further investigation and practical realization of seamless wireless-over-optical links in next-generation communication systems like B5G and 6G.