Return loss

About: Return loss is a research topic. Over the lifetime, 11090 publications have been published within this topic receiving 97603 citations.

Experimental study of a wearable aperture-coupled patch antenna for wireless body area network

Abstract: A new type of the wearable aperture-coupled patch antenna for 2.4 GHz wireless body area network (WBAN) application is proposed. The H-shaped slot in middle ground plane and rectangular ring microstrip feed line are optimized, so that it realizes the efficient electromagnetic coupling with the radiating element. The substrate layers are 2 mm thickness felt layers with relative permittivity of 1.2, and the other layers are copper foil tape (CFT) to ensure the performance of the antenna. Furthermore, the return loss, radiation pattern and gain are investigated in detail for the antenna under different bending curvature radius. Experimental results show a good agreement with simulation results. (C) 2017 Wiley Periodicals, Inc.

Design of compact Ku band microstrip antenna for satellite communication

Abstract: In the recent years antenna design appears as a mature field of research. It really is not the fact because as the technology grows with new ideas, fitting expectations in the antenna design are always coming up. A Ku-band patch antenna loaded with notches and slit has been designed and simulated using Ansoft HFSS 3D electromagnetic simulation tool. Multi-frequency band operation is obtained from the proposed microstrip antenna. The design was carried out using Glass PTFE as the substrate and copper as antenna material. The designed antennas resonate at 15GHz with return loss over 50dB & VSWR less than 1, on implementing different slots in the radiating patch multiple frequencies resonate at 12.2GHz & 15.00GHz (Return Loss -27.5, -37.73 respectively & VSWR 0.89, 0.24 respectively) and another resonate at 11.16 GHz, 15.64GHz & 17.73 GHz with return loss -18.99, -23.026, -18.156 dB respectively and VSWR 1.95, 1.22 & 2.1 respectively. All the above designed band are used in the satellite application for non-geostationary orbit (NGSO) and fixed-satellite services (FSS) providers to operate in various segments of the Ku-band.

A novel power divider integrated with siw and dgs technology

Abstract: In this paper, a novel power divider integrated with substrate integrated waveguide (SIW) and defected ground structures (DGS) techniques is proposed to provide both power dividing and flltering functions. The SIW technique holds advantages of low proflle, low-lost, mass-production, easy fabrication and fully integration with planar circuits. By integrating with defected ground structures (DGS) technique, the size and cost of system can be efiectively reduced as the proposed power divider has a function of flltering which leads to reduction of one fllter. In order to verify the design approach, the proposed power divider with equal power divisions at the center frequency of 8.625GHz is fabricated and measured. The measured results demonstrate that the insertion loss is less than 1.2dB and the input return loss less than 16dB across the bandwidth of 1.4GHz (FBW is 16%). Moreover, the imbalances of the amplitude and phase are less than 0.3dB and 0.5 degree, respectively.

Micromachined multilayer bandpass filter at 270 GHz using dual-mode circular cavities

Abstract: In this paper, we present a microfabricated fourth-order sub-THz WR-3.4 bandpass waveguide filter based on TM110 dual-mode circular-shaped cavity resonators. The filter operates at the center frequency of 270 GHz with fractional bandwidth of 1.85% and two transmission zeros are introduced in the upper and in the lower stopband using a virtual negative coupling. The microchip filter is significantly more compact than any previous dual-mode designs at comparable frequencies, occupying less than 1.5 mm2. Furthermore, in contrast to any previous micromachined filter work, due to its axially arranged interfaces it can be directly inserted between two standard WR-3.4 rectangular-waveguide flanges, which vastly improves system integration as compared to previous micromachined filters; in particular no custom-made split-block design is required. The cavities are etched in the handle layer of a silicon-on-insulator (SOI) wafer, and coupling is realized through rectangular slots fabricated in the SOI device layer. Couplings of the degenerate modes in one cavity are facilitated by means of small perturbations in the circular cavity shapes. The measured average return loss in the passband is −18 dB and worst-case return loss is −15 dB, and an insertion loss of only 1.5 dB was measured. The excellent agreement between measured and simulated data is facilitated by fabrication accuracy, design robustness and micromachined self-alignment geometries.

Analysis and design of lumped element Marchand baluns

Abstract: In this paper a novel design procedure for lumped element Marchand baluns is proposed. An analysis is performed on the balun structure in order to determine the conditions for ideal balun performance in terms of the lumped element values. The analysis is verified by two broadband designs centered around 22.75 GHz and differing only in terms of their impedance transformation ratio. EM simulation results on our proposed lumped element Marchand balun structure predicts an insertion loss of 4 dB and return loss of 40 dB at the design frequency of 22.75 GHz. The amplitude and phase imbalance is predicted to be better than 1 dB and 60, respectively obtained over a wide 15 GHz bandwidth.