Modified Ultra Wideband (UWB) Antipodal Vivaldi Antenna for 5

This paper presents a half triangular Comb-shaped slits edge Antipodal Vivaldi Antenna (Comb-AVA) as compared to the conventional Antipodal Vivaldi Antenna (AVA) design. This proposed antenna covers 20-40 GHz spectrum. This Comb-AVA antenna is designed for the 5G application which is addressed to cover a dualband 28/38 GHz frequencies. A half triangular comb-shaped slits edge structure is employed to investigate its effects on antenna parameters. This proposed Comb-AVA occupies a 25x8 mm2 of FR 4 substrate ( = 4.4, tan δ=0.02, thinkness 1.6 mm). It has impedance bandwidth (S11≤-10 dB) along 20-40 GHz spectrum and fractional bandwidth (FBW) ≥0.5. It means that the bandwidth is categorized as ultra wideband (UWB). In addition, there is 11 dB refinement of return loss in the CombAVA design at 38 GHz frequency. VSWR value is in range of 1.054 to 1.396. This proposed antena also has a wider angular width (3 dB) than the AVA. Higher directivity and gain is generated by Comb-AVA at 28 GHz. This proposed antenna has good performances and suitable for 5G application.

Performance of Groundplane Shaping in Four-Element Dualband MIMO Antenna

This work presents performance of groundplane shaping and its effect in four element dualband multiple input multiple output (MIMO) antenna. This proposed four element dualband MIMO antenna consists of four bowtie dipole antenna which operates at 1800 MHz (low frequency) and 2300 MHz (high frequency). This proposed four element dualband MIMO antenna occupies a 270 x 210 x  100 mm3  of FR 4 substrate. We use four types  of groundplane pattern i.e. full groundplane, cornered spatial groundplane,crossed middle groundplane, and spiral groundplane. These various grounplane patterns influence the performance of main parameters of dualband MIMO antenna. Cornered spatial groundplane pattern yields a largest bandwidth (VSWR ≤ 2) 282 MHz or 15.24% of center frequency at low frequency. Full groundplane pattern creates 135.2 MHz at high frequency. In addition, cornered spatial groundplane pattern also generates a lowest VSWR  that  is valued 1.21 at both low frequency and high frequency. The S parameters, basically both cornered spatial and full groundplane pattern produce a better return loss than two others. All four groundplane patterns deliver  equally a mutual coupling parameter.The last, this proposed four element dualband MIMO with various groundplane patterns gives a good farfield properties i.e. gain, radiation pattern, H-E field

Simple, Easy-use and Low-cost Software for Design of Single and Cascaded Microring Resonators Using Semi-numerical Method

Development of a simple, easy and low-cost software for designing of waveguide-coupled single and cascaded microring resonator (MRRs) using semi-numerical calculation based on transfer matrix method (TMM), is presented in this paper. The software uses a device model which is embedded on the high index contrast (HIC) structure of silicon-on-insulator (SOI) with monomodal cavity for TE-mode polarizations, operating around 1550 nm optical wavelength. The main aim of the software is to estimate the microring resonator performance parameters, such as free spectral range (FSR) and quality factor (Q-factor). The software is very simple and easy to use. With a standard laptop computer, it only takes few seconds to obtain transmission response, FSR and Q-factor of single MRR for varied waveguides separation distance and ring radius. The results were then verified using simulation method based on finite integration technique using 3D electromagnetic simulator, which need a high memory and processor of computer and take days to execute the simulation. We found only small discrepancy, which in averages are about 4.25% and 10.80% for FSR and Q-factor, respectively. In general, the results obtained from this software are closer to 3D electromagnetic simulation results