A 22-to-32 GHz 4-Beam 32-Element Polarization Reconfigurable Fully-Connected Fully-Bidirectional MIMO Transceiver for Emerging Space-Air-Ground-Sea Integrated Network

The current terrestrial network (TN) falls short in meeting the extensive coverage and seamless connectivity requirements. In contrast, the rapid advancement of non-terrestrial networks (NTN), such as low-earth orbit (LEO) satellite communication networks, offers the potential to supplement TN and achieve global wireless coverage. Ultimately, the integration of various networks gives rise to an integrated space-air-ground-sea network (ISAGSN). A critical aspect of realizing the ISAGSN is to enhance transceiver capabilities to support multiple networks and various polarizations. Figure 1, bottom left, depicts the existing phased-array transceivers architecture. In [1], the V-/H-polarization ports of patch antennas are individually linked to the TX/RX using double the number of antenna arrays to avoid additional insertion loss from the antenna switch. However, this arrangement led to poor isolation between the TX and RX paths and relied solely on the dual-polarization antenna. In [2], dual-linear polarization was utilized to achieve x2 data rate with x2 hardware cost. However, analogous to [1], this method did not support circular polarization. Conversely, authors in [3] proposed a receiver that could simultaneously accommodate linear polarization, dual-linear polarization, and circular polarization modes. Nonetheless, implementing the circular polarization mode involved a combination of two signal paths, resulting in only x1 data rate and a decrease in power efficiency of the system. In addressing these limitations, a polarization reconfigurable bi-directional transceiver architecture with an embedded reconfigurable coupler is proposed, with the capability to support all polarization modes, including dual-circular polarization, while incurring negligible power efficiency penalties. To the best knowledge of the authors, this is the first transceiver capable of supporting all polarization modes and allowing flexible switching between them.