Abstract: An ultra-wideband electromagnetic band gap (EBG) structure includes multiple EBG units in an array. Each EBG unit includes a power plane, a dielectric substrate and a ground plane from top to bottom. The power plane includes a patch, a coupled complementary split ring resonator (C-CSRR) and a plurality of semi-improved Z-bridge structures. Each edge of the patch is provided with a semi-improved Z-bridge structure. The C-CSRR is provided within a ring formed by the semi-improved Z-bridge structures. The Z-bridge structure includes a first horizontal branch, a first vertical branch, a second horizontal branch and a second vertical branch connected in sequence. The second vertical branch is connected to the patch. First horizontal branches of adjacent EBG units are connected to each other. A circuit board including the aforementioned EBG structure is also provided.

Abstract: The present disclosure belongs to the technical field of OAM antennas, and provides a frequency re-configurable OAM antenna in S band and a frequency reconfiguration method. The OAM antenna includes a lower dielectric substrate and multiple array units. Each array unit includes a metal patch, an upper dielectric substrate, an outer loop, an inner loop, a coaxial feeder, four metal probes, and four diodes. In the present disclosure, bias states of all the diodes of each array unit are controlled by applying a voltage; when all the diodes are in forward bias states, the antenna works at a high frequency; and when all the diodes are in reverse bias states, the antenna works at a low frequency. The frequency re-configurable OAM antenna in S band in the present disclosure has features of frequency reconfiguration and two OAM radiation modes, and has a stable gain over a broadband.

Abstract: This disclosure provides a perovskite light-emitting diode with an adjustable light field, including a glass layer, an anode, a hole transport layer, an emission layer, an electron transport layer and a cathode in sequence from top to bottom. The electron transport layer is provided with a periodic nano-grating structure.

Abstract: This disclosure provides a perovskite light-emitting diode with an adjustable light field, including a glass layer, an anode, a hole transport layer, an emission layer, an electron transport layer and a cathode in sequence from top to bottom. The electron transport layer is provided with a periodic nano-grating structure.