The Single-Position Method for Determining the Coordinates of a Radio-Frequency Source in the Near-Field Region

2009 ◽  
Vol 68 (8) ◽  
pp. 687-695
Author(s):  
L. I. Diduk ◽  
V. I. Nikolskii ◽  
S. N. Panychev
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
B. Varghese ◽  
O. Shramkova ◽  
P. Minard ◽  
L. Blondé ◽  
V. Drazic ◽  
...  

AbstractIn this paper, we report the experimental and numerical investigation of plane wave diffraction by an all-dielectric dual-material cuboid. Edge diffraction by a cuboid leads to the generation of a narrow, high intensity beam in the near-field region called a photonic jet. We examine the dependence of the jet behavior and orientation on the materials and dimensions of constitutive parts in the microwave frequency domain. The possibility to shift and deviate the resultant microwave jet in the near-field region of such a structure depending on the size of constitutive parts is demonstrated numerically. Experimentally, we observe a shift in the spatial position of the jet. The experimental asymmetric electric field profile observed in the far-field region is attributed to the input of multiple edge waves generated by the dual-material cuboid. The presented results may be scaled at different frequency bands such as optical frequencies for designing nanostructures enabling the focusing and deviation functionality and creation of new optical devices which would satisfy the needs of emerging nanophotonic applications.


Author(s):  
Ronith Stanly ◽  
Gopakumar Parameswaran ◽  
Bibin Sagaram

The influence of injector coking deposits on the spray field of single-hole mechanical port fuel injectors and multihole common rail direct injection (CRDi) injectors was studied using light scattering technique coupled with image processing and analysis. Instead of employing the traditional accelerated coking process to study injector spray field deterioration, in-service injectors were selected and cleaned using a commercial fuel system cleaning procedure. Variation in atomization characteristics of coked and cleaned injectors were observed based on the spatial distribution of fine, medium, and coarse droplets in the near-field region of the injector spray zone and analyzed as a function of the intensity of scattered light. The improvement in the atomization perceived by this method was compared with traditional techniques like spray cone angle measurement, speed characterization of spray jets, and weight reduction of injector nozzles and needles. It was observed that after the fuel system cleaning procedure, a reduction in the number of coarse droplets in the near-field region and an increase in the number of medium and finely sized droplets was observed, suggesting better atomization of fuel in the near field spray zone.


2017 ◽  
Vol 31 (17) ◽  
pp. 1786-1801 ◽  
Author(s):  
Brian L. Beaudoin ◽  
Gregory S. Nusinovich ◽  
Gennady Milikh ◽  
Antonio Ting ◽  
Steven Gold ◽  
...  

2021 ◽  
Author(s):  
Rajani K. Vijayaraghavan ◽  
Sean Kelly ◽  
David Coates ◽  
Cezar Gaman ◽  
Niall MacGearailt ◽  
...  

Abstract We demonstrate that a passive non-contact diagnostic technique, radio emission spectroscopy (RES), provides a sensitive monitor of currents in a low pressure radio frequency (RF) plasma. A near field magnetic loop antenna was used to capture RF emissions from the plasma without perturbing it. The analysis was implemented for a capacitively coupled RF plasma with an RF supply at a frequency of 13.56 MHz. Real-time measurements are captured in scenarios relevant to contemporary challenges faced during semiconductor fabrication (e.g. window coating and wall disturbance). Exploration of the technique for key equipment parameters including applied RF power, chamber pressure, RF bias frequencies and chamber wall cleanliness shows sensitive and repeatable function. In particular, the induced RES signal was found to vary sensitively to pressure changes and we were able to detect pressure and power variations as low as ~2.5 %/mtorr and ~3.5 %/watt, respectively, during the plasma processing during a trial generic plasma process. Finally, we explored the ability of RES to monitor the operation of a multiple frequency low-pressure RF plasma system (f1 = 2 MHz, f2 = 162 MHz) and intermixing products which suggests strongly that the plasma sheaths are the primary source of this non-linear diode mixing effect.


2018 ◽  
Vol 6 (2) ◽  
pp. 130-145
Author(s):  
Adekanmbi M ◽  
Abumere E.O ◽  
Amusan J.A

Light has been generated through Plasma using radio frequency source in 4Ft 40W disused fluorescent tube. As against the thermionic and incandescence source of running a fluorescent tube which is actually difficult to get started due to the resistance of the gases enclosed inside, a Radio Frequency signal of 30MHz  generated using a designed Hartley Oscillator is employed. The power of the signal generated is amplified from 231mW to 197.8W using a modeled inverter. The coupled Hartley oscillator and the inverter form an ionizing circuit. The gases inside fluorescent tube consist of mercury Vapor, argon, krypton or Neon. When sufficient energy is supplied to these gases, by the ionizing circuit, ionization and excitation takes place which makes otherwise neutral gases, to change state to a cloud of ionized gas called Plasma. When excited electrons in the gases return to the ground state they lose energy in packets called Photon. This Photon is ultraviolet light which is not visible to the human eye but when it strikes the walls of the tube coated with Phosphor it glows whereby light is generated. The high electric field Radio frequency circuit designed has generated light in a fluorescent tube without the use of starter and ballast. It has also generated light in otherwise “dead” or disused fluorescent bulbs.


Author(s):  
I Gede Sujana Eka Putra ◽  
Anthony Lee ◽  
I Made Tirta Mahayana ◽  
I Gede Agung Wicaksono Dharmayasa

Lecturer attendance record is required by the university to know the presence of lecturers in teaching in class. In general condition, lecturer attendance is recorded on the attendance sheet, or input to web application accessed on a class computer. However, there are some problems in its implementation so that at the end, lecturer presence is carried out using a manual form where the academic staff needs to re-enter the lecturer attendance data into the applications. Based on the above, the authors designed and developed a lecturer attendance information system to record lecturers' attendance using radio frequency identification technology by implementing a near field communication card (NFC Card). The device used to record and read presence data during lectures, by tapping an Mi-fare NFC card to an NFC reader / writer device. The flow of this research method begins with a literature study of NFC card, observe the flow of lecture attendance process and data recorded into lecturer attendance sheet, analyzing the database design, the system design which has compatible with NFC reader and writer devices, designed system interface and continue to develop system. The result is system consists of master data, system attendance, verification and reporting module. The results show that NFC card implementation is more practical for lecturers in conducting lecture attendance and NFC card could be tapped out into an NFC device at a maximum distance up to 7 cm with the reading angle relative to NFC reader/writer with range 00 until 300 can read NFC Card.


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