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A dual notched band UWB-BPF based on microstrip-to-short circuited CPW transition
This paper proposes a dual notched band ultra-wideband (UWB) bandpass filter (BPF) based on hybrid transition of microstrip and coplanar waveguide (CPW). The CPW in ground plane houses a stepped impedance resonator shorted at ends, and is designed to place its resonant modes within the UWB passband. The microstrips on the top plane are placed some distance apart in a back-to-back manner. The trans
Wideband low-profile aperture-coupled circularly polarized antenna based on metasurface
In this paper, a metasurface-based aperture-coupled circularly polarized (CP) antenna with wideband and high radiation gain is proposed and analyzed. The proposed antenna is comprised of coplanar waveguide coupling with 4 × 4 corner truncated square patches, which show compact size and low profile. The mechanism of the CP antenna is analyzed theoretically based on the mode analysis and equivalent
Analysis of HTS circular patch antennas including radome effects
In this paper, the resonant frequencies, quality factors and bandwidths of high superconducting circular microstrip patches in the presence of a dielectric superstrate loading have been studied using Galerkin testing procedure in the Hankel transform domain. The exact Green's function of the grounded dielectric slab is used to derive an electric field integral equation for the unknown current dis
Gain enhancement of UWB antenna using partially reflective surface
This paper proposes, a high gain, Fabry Perot cavity antenna with coplanar waveguide (CPW) fed ultra wide band (UWB) radiating element. The proposed antenna has flat edge arrow shape-based radiating element, which act as a main radiating element and responsible for UWB radiation. This UWB microstrip antenna is parasitically coupled with an array of square parasitic patches (PPs), which act as part
A fractal quad-band antenna loaded with -shaped slot and metamaterial for wireless applications
A novel concept of using fractal antenna with metamaterial and slot to achieve multiband operation is investigated. The antenna consists of an -shaped slot in the radiating monopole perturbs the surface current distribution; thereby increasing the total current path length which tends the antenna to further operate at 5.5 (upper WiMAX), 7.3 (satellite TV) and 9.9 GHz (X-band), respectively. The ex
An explicit single-layer frequency selective surface design with wide stop band frequency response
This manuscript deals with the development of a novel configuration of a wide-band single-layer frequency selective surface (FSS) for wide-band rejection applications. The established unit cell is composed of a simple circular ring on the top side of the substrate and a combined conductive element on the backside. Such an inclusion of conductive elements and accurate tuning of their dimensions end
EMC microwave absorber for outdoor applications
In some circumstances, electromagnetic compatibility testing must be performed not in a specialized anechoic chamber, but in an open space. However, typical absorbers used in anechoic chambers to absorb incident radiation and to reduce the amount of rays reflected from the walls and the floor, such as ferrite tiles and graphite cones, are not suitable in an open space. In this work, we present the
Optimization of wireless sensor network deployment for electromagnetic situation monitoring
Wireless sensor networks are an increasingly popular tool for monitoring various environmental parameters. They can also be used for monitoring the electromagnetic spectrum. Wireless sensors, due to their small size, typically have simplified radio receivers with reduced sensitivity and use small antennas. As a result, their effective performance area is similarly limited. This is especially impor
A 52-to-67 GHz dual-core push?push VCO in 40-nm CMOS
We present a continuously tunable 52-to-67 GHz push?push dual-core voltage-controlled oscillator (VCO) in a 40 nm bulk complementary metal?oxide?semiconductor (CMOS) technology. The circuit is suitable for 60 GHz frequency-modulated-continuous-wave radar applications requiring a continuously tunable ultra-wide modulation bandwidth. The LC-tank inductor is used to couple the two VCO cores. The fund
Plastic and metal additive manufacturing technologies for microwave passive components up to band
This paper illustrates the different possibilities given by additive manufacturing technologies for the creation of passive microwave hardware. The paper more specifically highlights a prototyping scheme where the 3D-printed plastic parts can be used as initial proofs of concept before considering more advanced 3D-printed parts (metal parts, for instance). First, a characterization campaign has be