International Journal

Modern telecommunications are moving towards (massive) multi-input multi-output (MIMO) systems in 5th generation (5G) technology, increasing the dimensionality of the systems dramatically. In this paper, the impairments of radio frequency (RF) power amplifiers (PAs) in a 3 × 3 MIMO system are compensated in both the time and the frequency domains. A three-dimensional (3D) time-domain memory polyno

In this paper, the design theory of an 8 GHz oscillator with a new structure of active dielectric resonator (DR) is presented. The new structure emphasizes on phase noise reduction by using only one active device. The proposed structure uses additional feedback from transistor to resonator in order to increase the quality factor. Measurement results report that phase noise is reduced to ?145.19 dB

A bottom-feed omni-directional CP (circularly polarized) antenna array is proposed in this letter. The antenna array is composed of four elements (two printed ZPS (zero-phase-shift) line loops and two half-wavelength dipoles). The four elements are fed with the same phase and amplitude. The ZPS line loops provide the horizontal polarization while the dipoles provide the vertical polarization. Ther

Now-a-days, far-field wireless power transfer/energy harvesting is underutilized due to the unavailability of proper methodology to design efficient system for maximum radio frequency (RF) power utilization. For efficient utilization of far-field RF energy an array/grid of rectenna, i.e. rectenna panel is required to generate the power from wireless signal. To minimize the engineering design phase

In this paper, a novel decoupling technique for closely spaced -plane patch antennas using defect ground structure (DGS) is proposed. The electric field coupling between the antennas is suppressed by etching DGS which consists of a pair of rectangular slots and four stubs on the ground plane. Moreover, unlike the other methods, the DGS is not etched in the middle of the antennas but loaded along t

A hybrid thin film multilayer antenna for automotive radar is presented in this work. A 2 × 8 aperture coupled stacked patch antenna array is realized on a single layer printed circuit board (PCB) using a novel thin film-based approach. Using a compact 180 phase difference power divider, inter-element spacing in a 2×2 sub-array is reduced. Measurement results show a 19% (67.9?82.5 GHz) impedance b

A polarization and band reconfigurable cross-slot antenna for multiband applications is presented in this paper. The antenna consists of four p?i?n diodes embedded in the cross-shaped slot in a ground plane and excited by a microstrip feed line. The p?i?n diodes are placed in such a way that they produce multiple bands, with linearly and circularly polarized (CP) radiation. By switching the states

In this study, a new ultra-wideband (UWB) band-edge selectivity antenna with a modified radiation slot using defected ground structure (DGS) is presented to obtain bandpass filtering reflection coefficient and gain performance. The well-designed DGS is designed on backside metallic of the substrate and can be seen as a low-pass filter that provides a good roll-off at a higher frequency. By connect