Gain enhancement of microstrip patch antenna using artificial magnetic conductor

The paper presents an artificial magnetic conductor (AMC) structure to enhance the gain of the double microstrip patch antenna. By placing this kind of metamaterial in between the two Rogers RT5880 substrates, the antenna achieved lots of improvement especially in terms of size miniaturization, bandwidth, return loss, gain and efficiency. The antenna is intended to operate at 16 GHz where the prospect fifth generation (5G) spectrum might be located. Integration of AMC structure into the proposed antenna helps to improve nearly 16.3% of gain and almost 23.6% of size reduction

Compact bidirectional circularly polarized dedicated short range communication antenna for on‐board unit vehicle‐to‐everything applications

This article presents a newly circularly polarized (CP) antenna for V2X's dedicated short range communications applications. Its CP characteristic is enabled by a 70 Ω sequential phase feeding network and sequential rotation technique designed on top of the substrate. It has features of ≈90° phase difference in sequence between ports of S 21 = 2.4°, S 31 = −87°, S 41 = −180°, and S 51 = −276°, resulting in a 2.19 dB axial ratio centered at 5.9 GHz. The length of the SP feeding network to each ports designed in the different form of meander lines are the key to control the generated phase at the center frequency It also contributes to the smaller final size of 0.59λ × 0.59λ . The proposed antenna operated from 5.850 to 5.925 GHz with a gain between 4 and 6 dBi. The gains are radiated in bidirectional mode due to the presence of the complimentary dipoles located on the opposite side of the substrate. These features indicate the suitability of the proposed antenna in compliance to the ITS‐G5 OBU V2X standard

A triangular MIMO array antenna with a double negative metamaterial superstrate to enhance bandwidth and gain

Multiple-input-multiple-output (MIMO) array antenna integrated with the double negative metamaterial superstrate is presented. The triangular metamaterial unit cell is designed by combining two triangular elements positioned in complementary on the same plane at different sizes. Such design with more gaps is used to excite rooms for more capacitance effects to shift the resonance frequency thus enlarging the bandwidth of the MIMO antenna. The unit cell is arranged in 7 × 7 periodic array created a superstrate metamaterial plane where the Cstray exists in parallel between the two consecutive cells. It is found that the existence of Cstray and gaps for each unit cells significantly influenced the bandwidth of the MIMO antenna. The higher value of the capacitance will lead to the negativity of permittivity. The superstrate plane is then located on top of the 4 × 2 MIMO with a gap of 5 mm. The integration resulted in improving the bandwidth to 12.45% (5.65-6.4GHz) compared to only 3.49% bandwidth (5.91-6.12GHz) of the MIMO antenna itself. Moreover, the negative permeability characteristic is created by a strong magnetic field between the complementary unit cells to have 14.05-dBi peak gain. Besides that, the proposed antenna managed to minimize the mutual coupling and improve the mean effective gain, envelope correlation coefficient, and multiplexing efficiency

A triangular MIMO array antenna with a double negative metamaterial superstrate to enhance bandwidth and gain

Multiple-input-multiple-output (MIMO) array antenna integrated with thedouble negative metamaterial superstrate is presented. The triangularmetamaterial unit cell is designed by combining two triangular elements posi-tioned in complementary on the same plane at different sizes. Such designwith more gaps is used to excite rooms for more capacitance effects to shift theresonance frequency thus enlarging the bandwidth of the MIMO antenna. Theunit cell is arranged in 7×7 periodic array created a superstrate metamaterialplane where theCstrayexists in parallel between the two consecutive cells. It isfound that the existence ofCstrayand gaps for each unit cells significantlyinfluenced the bandwidth of the MIMO antenna. The higher value of thecapacitance will lead to the negativity of permittivity. The superstrate plane isthen located on top of the 4×2 MIMO with a gap of 5 mm. The integrationresulted in improving the bandwidth to 12.45% (5.65-6.4GHz) compared toonly 3.49% bandwidth (5.91-6.12GHz) of the MIMO antenna itself. Moreover,the negative permeability characteristic is created by a strong magnetic fieldbetween the complementary unit cells to have 14.05-dBi peak gain. Besidesthat, the proposed antenna managed to minimize the mutual coupling andimprove the mean effective gain, envelope correlation coefficient, and mul-tiplexing efficiency