In order to solve the coupling problem of the wideband dual-polarization array of MIMO antennas, a decoupling method combining wideband array-antenna decoupling surface (WADS) and cross-type dielectric resonator is proposed, and the decoupling design is verified by simulation of $2 \times1$ compact wideband dual-polarization array antenna. According to the simulation results, the E-plane coupling is increased from -17dB to -22dB, and the H-plane coupling is increased from -18 dB to -25 dB in the 2.1-3 GHz operating frequency band, and the antenna array with decoupling structure still has good radiation characteristics. The decoupling method proposed in this paper has great application potential for broadband dual-polarization base station arrays in 5 G systems.

This letter proposes a pattern- and polarized-reconfigurable magneto-electric dipole antenna. Based on the existing traditional magneto-electric dipole antenna, The PIN diodes are added to regulate the radiation structure of the antenna. By changing the trend of its surface current, four different radiation states are generated, which can achieve two types of circularly polarized radiation and two types of linearly polarized beam deflection radiation. They have the same operating frequency band covering (1.6 to 1.9) GHz (17%). For circularly polarized radiation states, the proposed antenna has a 3 dB axial ratio (AR) beamwidth ranging from -100 degrees to +100 degrees and high cross polarization. For beam deflection states, the proposed antenna provides the function of beam scanning from +/- 15 degrees to +/- 35 degrees by changing the operating frequency. In order to verify the reliability of the simulation, a prototype is made with 3-D printing technology. The experimental results are in good agreement with the simulation results, proving that the antenna has good performance.

A magneto-electric (ME) dipole reflect-transmit-array (RTA) antenna that integrates the transmission array and the reflection array is proposed in this paper. When the antenna is fed with circularly polarized waves under different polarizations, the proposed antenna unit can produce differentiated responses, which transmitting or reflecting left hand circularly polarized (LHCP) waves. By rotating the magnetic electric dipole structure, the phase of the antenna unit can be controlled. To verify the performance of the proposed antenna, a $15 \times 15$ antenna array is designed and simulated. The antenna array operates at 8 GHz, with peak gains of 25.6dBi and 26 dBi for transmission and reflection, respectively, corresponding to aperture efficiencies of 37.3% and 40.9%. Simulated results show that the antenna has excellent transmission and reflection performance, and can adapt to various wireless communication application environments.

This paper proposes a broadband circularly polarized magneto-electric dipole antenna fed by dual ridge waveguide. Unlike traditional magneto-electric dipole antennas, the proposed antenna uses a dual ridge waveguide at the bottom of the radiation structure for feeding, achieving an impedance bandwidth of 1.77GHz to 5.47GHz (relative bandwidth of 102%). In order to achieve broadband circularly polarized performance, the antenna's electric dipoles are designed with two pairs of L-shaped patches with significant size differences and optimized accordingly, achieving a circularly polarized bandwidth of 3.77 GHz to 5.42 GHz (relative bandwidth of 36 % ). In addition, the antenna maintained a gain of more than 4dBi in the operating frequency band, demonstrating good performance.

In this paper, a high-isolation broadband MIMO antenna is designed, which consists of two symmetrical radiation units, and two symmetrically open hexagonal resonant rings are printed on the front of the substrate, and small hexagons are placed in the ring to achieve a wide frequency band. To improve the isolation between the antenna ports, a stepped slot is introduced on the ground plate on the back of the substrate and a resonant branch is inserted to reduce coupling within the operating band. The simulation results show that the working frequency band range of the antenna is 6.39GHz~7.71GHz, The relative bandwidth is around 19%.the isolation between the two ports of the antenna reaches more than 17dB in the entire wide band, and the maximum gain of the antenna in the broadband is 5.1dBi, which has good radiation performance .

In the field of electronic intelligence reconnaissance, the size of the short-wave antenna unit of airborne equipment is too large, and for the large longitudinal size of the logarithmic periodic antenna (LPDA), this paper proposes a miniaturized short-wave logarithmic-periodic antenna that can be conformal and conformalized. The antenna consists of 9 conformal bow tie dipole elements, cross-fed by parallel ribbon transmission lines, and then connected to a cylindrical surface to achieve conformity, so as to be used in vehicles. By turning the conventional dipole array antenna into a triangular bow tie array antenna, the size of the antenna has been reduced, and the antenna length is only 2.2m, realizing miniaturization. The simulation results show that the VSWR of the antenna from 52MHz to 221MHz is less than 2, the relative bandwidth is 123.8%, and the maximum gain can be up to 6dBi, which can be well used in the VHF band.

This article designs a reconfigurable-beam magnetoelectric dipole antenna withbroadband, which is mainly composed of two vertically symmetrical metal plates, a horizontal dipole (with four diodes), and a floor with an X-shaped slot. The antenna is fed through slot coupling. The operating frequency range of the antenna is 6.09GHz to 7.76GHz. By controlling the switch of the diode, the surface current of the horizontal dipole is changed, thereby achieving beam reconstruction of the antenna.