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Multiamino‐terminated telechelic polydimethylsiloxane (MATTPS) was synthesized via aza‐Micheal reaction and amidation reaction and subsequently employed as cross‐linkers of polysiloxane containing γ‐chloropropyl groups (CPPS) for preparing a series of high‐temperature vulcanized silicone rubber (MCSR/MATTPS). The curing, mechanical, and thermal properties of MCSR/MATTPS were studied through rheometry, mechanical testing, and thermogravimetric analysis (TGA). MCSR/MATTPS exhibits optimal mechanical properties with a tensile strength of 9.52 MPa and tear strength of 45.4 kN/m when the molar ratio of [N–H]/[CH2CH2CH2Cl] is of 1, which is attributed to the formation of concentrative cross‐linking in the three‐dimensional polymer networks. The thermal behaviors of MCSR/MATTPS display a two‐step weight loss process by heating in nitrogen whereas more than two weight loss process in air. TGA results indicate that the introduction of aliphatic long chain and carbonyl groups in the structure of MATTPS has little negative effect on the thermal stability of MCSR/MATTPS.

In this paper, a dual‐polarized cross‐dipole antenna with wide beam and high isolation is designed and analyzed for base station. The proposed antenna consists of two planar cross dipoles with four square patches, two L‐shaped microstrip lines, two ground plates, four parasitic patches, and a reflector. The square patches are placed between the center of cross dipoles to couple with L‐shaped microstrip lines. By introducing the parasitic patches, the wide beam can be realized. The measured results show that the proposed antenna achieves an impedance bandwidth (|S11| < −10 dB) of about 18.7% (1.9‐2.35 GHz) and an isolation better than 30 dB. A measured gain of 5.7 dBi and a half‐power beamwidth over 120° at the center frequency are obtained. Furthermore, the size of the proposed antenna is only 0.5λ0 × 0.5λ0 × 0.22λ0 (λ0 is wavelength at the center frequency).

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A form of reflective half-wave plate based on all-dielectric 3D-printed metasurface is proposed in this paper. The element of the proposed reflective half-wave plate consists of a novel hexagonal prism dielectric resonator (HPDR), a square substrate and a ground plane. The designed HPDR element can effectively convert the incident linearly polarized (LP) waves into the reflected circularly polarized (CP) waves. Meanwhile, an approximately linear reflection phase ranging over 360 • of HPDR element is realized by varying the height of HPDR, which can significantly simplify the design procedure. In addition, based on the proposed HPDR element, a CP dielectric reflectarray antenna is designed. In order to verify the feasibility of the proposed design method, the dielectric reflectarray antenna with LP feeding is fabricated and measured, which can achieve a 1 dB gain bandwidth of 17.9% and a 3 dB axial-ratio bandwidth of 15%. A good agreement between the simulation and measurement is also observed. To the best of authors' knowledge, the broadband CP dielectric reflectarray antenna based on all-dielectric 3D-printed metasurface may be the first ever reported.

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In this paper, a tunable power divider (PD) with a good band-pass filtering response using quarter-wavelength stepped impedance resonators (SIRs) is presented. By appropriately adjusting the impedance and electrical length ratio of SIR, the proposed structure can achieve wide stopband performance. Meanwhile, four varactor diodes are loaded to the external resonators to achieve electrical reconfiguration. In addition, a pair of transmission zeros (TZs) can be generated by applying source and load coupling on each side of the passband, which can effectively improve passband selectivity and out-of-band rejection. In order to verify the feasibility of the proposed design method, a prototype circuit of the proposed filtering power divider (FPD) with tunable center frequency is simulated, fabricated and measured. A good agreement between the simulation and measurement results is observed.