Vortex Beam Optimization Design of Concentric Uniform Circular Array Antenna with Improved Array Factor

2021 ◽  
Vol 36 (7) ◽  
pp. 830-837
Author(s):  
Qiang Feng ◽  
Yifeng Lin ◽  
Yushan Zheng ◽  
Long Li
Keyword(s):  
Simulation Model ◽  
Optimization Design ◽  
Near Field ◽  
Electromagnetic Simulation ◽  
Vortex Beam ◽  
Circular Array ◽  
Power Conservation ◽  
Beam Radiation ◽  
Low Sidelobe ◽  
Measurement Results

In this paper, an improved array factor of the concentric uniform circular array (CUCA) antenna is proposed for the orbital angular momentum (OAM) vortex beam optimization design. From the perspective of the radiation pattern’s power conservation principle, a correction factor is introduced to the conventional array factor of CUCA. Then, based on the improved array factor, by adjusting the rings’ radii parameters of the CUCA, we optimize the vortex beam’s sidelobe level through the generic algorithm (GA). Two different CUCA antenna model are calculated as examples to further illustrate the effectiveness of the improved array factor. Subsequently, an electromagnetic simulation model of two rings CUCA antenna is built at C band for generating low sidelobe vortex beam carrying OAM mode. The electromagnetic simulation model of the designed CUCA antenna is also fabricated and measured. The corresponding antenna far-field vortex beam radiation pattern and near-field vortex wave electric field distributions are measured. The simulation results and the measurement results are in good agreement. The proposed designs of antenna and OAM vortex beam regulation are expected to be used for 5G and 6G communications applications

An approach to determine solution properties in micro pipes by near-field microwave microscopy

2021 ◽  
Author(s):  
Yahui Wang ◽  
Ziqian Wei ◽  
Yujie Chen ◽  
Quanxin Zhou ◽  
Yubin Gong ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Simulation Model ◽  
Near Field ◽  
Electromagnetic Properties ◽  
Electromagnetic Simulation ◽  
Solution Properties ◽  
Microwave Microscopy ◽  
Photinia X Fraseri ◽  
Saline Solutions ◽  
Non Destructive

Abstract In this article, we propose a quantitative, non-destructive and noninvasive approach to obtain electromagnetic properties of liquid specimens utilizing a home-designed near-field microwave microscopy. The responses of aqueous solutions can be acquired with varying concentrations, types (CaCl2, MgCl2, KCl and NaCl) and tip-sample distances. An electromagnetic simulation model also successfully predicts the behaviors of saline samples. For a certain type of solutions with varying concentrations, the results are concaves with different bottoms, and the symmetric graphs of concave extractions can clearly identify different specimens. Moreover, we obtain electromagnetic images of capillaries with various saline solutions, as well as a photinia x fraseri Dress leaf.

scholarly journals Multi-Probe Measurement System Based on Single-Cut Transformation for Fast Testing of Linear Arrays

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1744
Author(s):  
Fernando Rodríguez Varela ◽  
Manuel José López Morales ◽  
Rubén Tena Sánchez ◽  
Alfonso Tomás Muriel Barrado ◽  
Elena de la Fuente González ◽  
...  
Keyword(s):  
Measurement System ◽  
Near Field ◽  
Linear Measurement ◽  
Complete Characterization ◽  
Linear Arrays ◽  
Full Characterization ◽  
X Band ◽  
Measurement Results ◽  
The Many ◽  
3D Information

This paper introduces a near-field measurement system concept for the fast testing of linear arrays suited for mass production scenarios where a high number of nominally identical antennas needs to be measured. The proposed system can compute the radiation pattern, directivity and gain on the array plane, as well as the array complex feeding coefficients in a matter of seconds. The concept is based on a multi-probe antenna array arranged in a line which measures the near field of the antenna under test in its array plane. This linear measurement is postprocessed with state-of-the-art single-cut transformation techniques. To compensate the lack of full 3D information, a previous complete characterization of a “Gold Antenna” is performed. This antenna is nominally identical to the many ones that will be measured with the proposed system. Therefore, the data extracted from this full characterization can be used to complement the postprocessing steps of the single-cut measurements. An X-band 16-probe demonstrator of the proposed system is implemented and introduced in this paper, explaining all the details of its architecture and operation steps. Finally, some measurement results are given to compare the developed demonstrator with traditional anechoic measurements, and show the potential capabilities of the proposed concept to perform fast and reliable measurements.

Computer-Aided Analysis and Measurement of an Interconnection System

2011 ◽  
Vol 308-310 ◽  
pp. 2279-2285
Author(s):  
Wei Chen Lee ◽  
Hill Wu
Keyword(s):  
Simulation Model ◽  
Frequency Domain ◽  
Insertion Loss ◽  
Return Loss ◽  
Design Phase ◽  
Electrical Characteristics ◽  
Impedance Mismatch ◽  
Measurement Results ◽  
Computer Aided Analysis ◽  
Computer Aided

The electrical characteristics of an interconnection system, which include impedance, insertion loss, and return loss, can greatly affect its performance as the signal speed increases. The objective of this research was to understand the discrepancy between the computer-aided analysis and measurement results of an interconnection system, so that a more accurate prediction of the electrical characteristics of this system can be made during the design phase. It was discovered that in both the time and frequency domain the computer-aided analysis results were consistent with the measurement results. Given these conclusions the simulation model was modified to improve the impedance mismatch within the interconnection system. It was found that by properly designing the antipad, the impedance mismatch can be greatly reduced.

scholarly journals Transparent Metasurface for Generating Microwave Vortex Beams with Cross-Polarization Conversion

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2448 ◽  
Author(s):  
Hongyu Shi ◽  
Luyi Wang ◽  
Mengran Zhao ◽  
Juan Chen ◽  
Anxue Zhang ◽  
...  
Keyword(s):  
Transmission Loss ◽  
Phase Distribution ◽  
Polarization Conversion ◽  
Vortex Beam ◽  
Cross Polarization ◽  
Measurement Results ◽  
Vortex Beams ◽  
Simulation Results ◽  
Polarization Level ◽  
Transmission Phase

In this paper, metasurfaces with both cross-polarization conversion and vortex beam-generating are proposed. The proposed finite metasurface designs are able to change the polarization of incident electromagnetic (EM) waves to its cross-polarization. In addition, they also can modulate the incidences into beams carrying orbital angular momentum (OAM) with different orders ( l = + 1 , l = + 2 , l = − 1 and l = − 2 ) by applying corresponding transmission phase distribution schemes on the metasurface aperture. The generated vortex beams are at 5.14 GHz. The transmission loss is lower than 0.5 dB while the co-polarization level is −10 dB compared to the cross-polarization level. The measurement results confirmed the simulation results and verified the properties of the proposed designs.

scholarly journals Near-Field Antenna Measurements with Manual Collection of the Measurement Samples

2020 ◽  
Vol 18 ◽  
pp. 17-22
Author(s):  
Fabian T. Faul ◽  
Hans-Jürgen Steiner ◽  
Thomas F. Eibert
Keyword(s):  
Near Field ◽  
Field Measurements ◽  
Controlled Environment ◽  
Positioning System ◽  
Probe Position ◽  
Site Testing ◽  
Error Level ◽  
Measurement Results ◽  
Anechoic Chambers ◽  
Chamber Measurements

Abstract. Near-field measurements are commonly performed in anechoic chambers which limits the flexibility of the measurements and requires high precision equipment to achieve exact results. In this contribution, we investigate a simple near-field measurement setup which does not use any sophisticated positioning system nor operates in a controlled environment. Instead, the probe antenna is moved by an operator person while the probe position is measured by a laser tracker. This implies that the measurement results will have a higher error level in comparison with antenna chamber measurements. However, excellent error levels are not always necessary, especially when it comes to on-site testing of the principle functionality of antennas. Measurement results are shown to illustrate the performance of the system.

Study of fractional optical vortex beam in the near-field

2020 ◽  
Vol 475 ◽  
pp. 126268
Author(s):  
Sujai Matta ◽  
Pramitha Vayalamkuzhi ◽  
Nirmal K. Viswanathan
Keyword(s):  
Near Field ◽  
Optical Vortex ◽  
Vortex Beam
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