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Novel sunflower MIMO fractal antenna with low mutual coupling and dual wide operating bands
A novel multiple-input and multiple-output (MIMO) fractal antenna excited by a coplanar waveguide was investigated in this study. A novel technique was used to improve the isolation of 20 dB between the dual radiating elements by inserting a strip line into the outer edges of the ground plane. A sunflower structure was used to configure the antenna in three steps. At each step, an additional sunfl
Center frequency and bandwidth switchable substrate integrated waveguide filters
This paper presents center frequency and bandwidth switchable substrate integrated waveguide filters loaded with PIN diodes. The diodes are added in the slot on the surface of the resonators to switch the resonant frequencies and the coupling coefficients. Although the introduction of the slot causes extra radiation loss, it is small and acceptable. The proposed center frequency switchable filter
Target range?angle estimation based on time reversal FDA-MIMO radar
Different from traditional multiple-input and multiple-output (MIMO) radar, the frequency diverse array MIMO (FDA-MIMO) radar generates beampattern that is dependent on both range and angle, making it applicable for joint range?angle estimation of targets. In this paper, we propose a novel time reversal based FDA-MIMO (TR-FDA-MIMO) approach for target detection. Based on the time reversal theory,
A low-profile wideband circularly polarized MIMO antenna with pattern and polarization diversity
The present work describes a unique planar low-profile wideband circularly polarized Multiple-Input and Multiple-Output (MIMO) antenna operating in the X-band, with pattern and polarization diversity over the entire axial-ratio bandwidth (ARBW). The design is unique in the sense that a simple grounded stub introduced between two linearly polarized monopole antennas has been used to realize wideban
Quintuple-mode wideband bandpass filters with improved out-of-band rejection
This paper presents design of quintuple-mode wideband bandpass filters, implemented with off-centered perturbed metallic cylinders in a rectangular waveguide cavity. Three perturbation cylinders are placed at the bottom of the rectangular waveguide cavity, along with a pair of perpendicularly fed coaxial lines; excite five quasi-transverse magnetic modes to realize the desired passband. The height
Dual band circular polarized bow tie slotted patch antenna over high impedance surface for WiMAX application
A novel planar dual-band bow-tie slotted patch antenna backed by high-impedance surface (HIS) is designed at 2.5 and 3.5 GHz for wireless application. The antenna employs coplanar waveguide fed patch and bow-tie slot as radiating elements. The bow-tie slot enables dual-band operation for the antenna. The HIS is made asymmetric in design to make it polarization dependent. This polarization-dependen
Wireless sensor node remote supply using a compact stacked rectenna array with voltage multipliers at 2.45 GHz
This paper presents compact rectenna arrays for ambient RF energy harvesting on the 2.45 GHz ISM band. The arrays are based on four and nine series-connected rectenna cells. Each cell is composed of a stacked fractal antenna and an RF-to-dc conversion circuit. The antenna is a compact third Koch fractal shape, fed by a coaxial probe for more compactness. The conversion circuit is a full-wave recti
MRF volume 12 issue 3 Cover and Back matter
MRF volume 12 issue 3 Cover and Front matter
Triple-band operation achievement via multi-input multi-output antenna for wireless communication system applications
A multi-input multi-output (MIMO) antenna is designed and discussed for multi-band applications. The constituent antennas are composed of four L-shaped elements and a ground plane. When placed beside each other to form a MIMO antenna, a T-bar shaped parasitic structure is also embedded between the antennas on the backside of the substrate to increase the inter-element isolation. The triple-band pe