Dual-Linearly Polarized Transmission-Reflection-Integrated Metasurface for Full-Space Beam Generation with Independent Power Allocation

Existing multi-polarized transmission–reflection-integrated metasurfaces (TRIMs) usually suffer from fixed or coupled beam power allocation, making it difficult to independently prescribe the beam power ratios in the transmission and reflection spaces. To address this issue, a dual-linearly polarized TRIM with independently prescribed beam power ratios in the two half-spaces is proposed in this paper. The proposed TRIM is based on a quad-channel metasurface unit-cell, which provides two orthogonal transmission channels and two orthogonal reflection channels. By independently rotating the top and bottom patches, the amplitude ratio between the two transmission channels and that between the two reflection channels can be separately controlled, while 1-bit phase compensation is simultaneously maintained. To validate the proposed concept, a TRIM operating at 16 GHz is designed. Four design cases with different beam power ratios are investigated, verifying the independent power allocation capability in the two half-spaces. Furthermore, one representative design case is implemented, fabricated, and measured. The measured results agree well with the simulated ones. This work provides a solution for full-space dual-linearly polarized beam generation with independently prescribed beam power ratios in the two half-spaces, showing potential for bidirectional ground communication scenarios.