Journal articles: 'Right hand circularly polarized'

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Guo, Mengchao, Kan Zhou, Xiaokun Wang, Haiyan Zhuang, Dongming Tang, Baoshan Zhang, and Yi Yang. "Research of the impact of coupling between unit cells on performance of linear-to-circular polarization conversion metamaterial with half transmission and half reflection." International Journal of Modern Physics B 32, no. 10 (April 13, 2018): 1850124. http://dx.doi.org/10.1142/s0217979218501242.

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In this paper, the impact of coupling between unit cells on the performance of linear-to-circular polarization conversion metamaterial with half transmission and half reflection is analyzed by changing the distance between the unit cells. An equivalent electrical circuit model is then built to explain it based on the analysis. The simulated results show that, when the distance between the unit cells is 23 mm, this metamaterial converts half of the incident linearly-polarized wave into reflected left-hand circularly-polarized wave and converts the other half of it into transmitted left-hand circularly-polarized wave at 4.4 GHz; when the distance is 28 mm, this metamaterial reflects all of the incident linearly-polarized wave at 4.4 GHz; and when the distance is 32 mm, this metamaterial converts half of the incident linearly-polarized wave into reflected right-hand circularly-polarized wave and converts the other half of it into transmitted right-hand circularly-polarized wave at 4.4 GHz. The tunability is realized successfully. The analysis shows that the changes of coupling between unit cells lead to the changes of performance of this metamaterial. The coupling between the unit cells is then considered when building the equivalent electrical circuit model. The built equivalent electrical circuit model can be used to perfectly explain the simulated results, which confirms the validity of it. It can also give help to the design of tunable polarization conversion metamaterials.

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Khandelwal, Mukesh Kumar, Binod Kumar Kanaujia, Santanu Dwari, Sachin Kumar, and Anil Kumar Gautam. "Triple band circularly polarized compact microstrip antenna with defected ground structure for wireless applications." International Journal of Microwave and Wireless Technologies 8, no. 6 (March 12, 2015): 943–53. http://dx.doi.org/10.1017/s1759078715000288.

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Asymmetric slits loaded irregular shaped microstrip patch antenna with three different ground structures is proposed. All three antennas show triple band characteristics. First antenna with regular ground plane resonates at 1.95, 2.4, and 4.90 GHz with good radiation characteristics and shows right-hand circular polarization at 1.95 GHz. 18.75% of compactness is achieved with triple band characteristics. Further, same patch is used with different defected ground structures. Second antenna resonates at 1.85, 2.4, and 4.85 GHz with suppressed cross-polarization level and antenna shows right-hand circular polarization at 1.85 and 4.85 GHz. Compactness is further improved to the value of 22.91%. The third antenna resonates at 1.95, 2.4, and 4.85 GHz with better gain and radiation characteristics and antenna shows right-hand circular polarization at 1.95 and 2.4 GHz. The small frequency ratio f2/f1 is achieved and the value of f2/f1 is 1.29 and 1.23 for second and third configuration, respectively. Proposed structures show right-hand circularly polarized with suppressed left-hand circularly polarized radiations and suitable for fixed mobile wireless communication applications. All structures are analyzed using Ansoft HFSS v.14 based on finite element method and measured results satisfy the simulated results.

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Farahani, Mohammadmahdi, Mohammad Akbari, Mourad Nedil, Abdel-Razik Sebak, and Tayeb A. Denidni. "Millimeter-Wave Dual Left/Right-Hand Circularly Polarized Beamforming Network." IEEE Transactions on Antennas and Propagation 68, no. 8 (August 2020): 6118–27. http://dx.doi.org/10.1109/tap.2020.2986678.

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Vaidya, Avinash R., Rajiv K. Gupta, Sanjeev K. Mishra, and Jayanta Mukherjee. "Right-Hand/Left-Hand Circularly Polarized High-Gain Antennas Using Partially Reflective Surfaces." IEEE Antennas and Wireless Propagation Letters 13 (2014): 431–34. http://dx.doi.org/10.1109/lawp.2014.2308926.

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Röhricht, B., P. Eschle, S. Dangel, and R. Holzner. "Nonlinear Behavior of Circularly Polarized Laser Beams Propagating through Sodium Vapor." Zeitschrift für Naturforschung A 48, no. 5-6 (June 1, 1993): 621–23. http://dx.doi.org/10.1515/zna-1993-5-602.

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Abstract A variety of surprising effects arise from the nonlinear light-matter interaction of circularly polarized laser light propagating through sodium vapor. We present experimental evidence for an asymmetry in the absorption of left hand and right hand circularly polarized light as well as for the creation of a collimated light beam of apposite polarization within the light-matter interaction region. Both effects are not yet explained by common theories.

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Mjølhus, E., and T. Hada. "Oblique stability of circularly polarized MHD waves." Journal of Plasma Physics 43, no. 2 (April 1990): 257–68. http://dx.doi.org/10.1017/s002237780001477x.

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The stability of finite-amplitude weakly dispersive circularly polarized MHD wave trains with respect to oblique modulations is investigated. The mathematical model is a multi-dimensional extension of the DNLS equation. We have found that the right-hand-polarized wave, which is stable with respect to parallel modulations, is unstable with respect to certain oblique modulations for most primary wavenumbers.

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Nalimov, A. G., and E. S. Kozlova. "Inversion of the longitudinal component of spin angular momentum in the focus of a left-handed circularly polarized beam." Computer Optics 44, no. 5 (October 2020): 699–706. http://dx.doi.org/10.18287/2412-6179-co-761.

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It has been shown theoretically and numerically that in the sharp focus of a circularly polarized optical vortex, the longitudinal component of the spin angular momentum vector is inverted. Moreover, if the input light to the optical system is left-hand circularly polarized, it has been shown to be right-hand polarized in the focus near the optical axis. Since this effect occurs near the focus where a backward energy flow takes place, such an inversion of the spin angular momentum can be used to detect the backward energy flow.

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Etemadpour, R., and N. Sepehri Javan. "Effect of super-thermal ions and electrons on the modulation instability of a circularly polarized laser pulse in magnetized plasma." Laser and Particle Beams 33, no. 2 (April 8, 2015): 265–72. http://dx.doi.org/10.1017/s0263034615000117.

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AbstractThe modulation instability of a circularly polarized laser pulse in a magnetized non-Maxwellian plasma is investigated. Based on a relativistic fluid model, the nonlinear interaction of an intense circularly polarized laser beam with a non-Maxwellian magnetized plasma is described. Nonlinear dispersion relation and growth rate of the instability for left- and right-hand polarizations are derived. The effect of temperature, external magnetic field, value of Kappa and state of polarization on the growth rate are analyzed. It is shown that the growth rate increases with increase in the magnetic field for the right-hand polarization and inversely it decreases for the left-hand one. Also it is observed that existence of super-thermal particles causes the decrease in the growth.

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Akgol, Oguzhan, Olcay Altintas, Emin Unal, Muharrem Karaaslan, and Faruk Karadag. "Linear to left- and right-hand circular polarization conversion by using a metasurface structure." International Journal of Microwave and Wireless Technologies 10, no. 1 (November 10, 2017): 133–38. http://dx.doi.org/10.1017/s1759078717001192.

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By using a metasurface (MS) structure, a linearly polarized wave is converted to circularly polarized waves. Both right- and left-handed circular polarizations (RHCPs and LHCP) are obtained by a simple configuration in the proposed structure which consists of 16 unit cells arranged in a 4 × 4 layout. Each unit cell contains five horizontal and parallel strips embedded in a rectangular frame in which a single diagonal strip is placed from one corner to the opposed one. It is shown that the orientation of the diagonal line determines the handedness of the converted signal to be either LHCP or RHCP. In order to show the working conditions of the MS structure, scattering parameters are found for both co-polarized and cross-polarized responses. Axial ratio, an indicator for polarization conversion, is then obtained by dividing cross-polar response to co-polar response to demonstrate the transformation. The structure works for horizontally and vertically polarized linear waves in a wide band frequency range which is approximately 510 MHz. Since the suggested MS model is composed of a simple geometry for polarization conversion, it can be easily adjusted in any desired frequency bands for a variety of applications from the defence industry to medical, education, or communication areas.

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Karamzadeh, Saeid, Vahid Rafiei, and Hasan Saygin. "Development and Miniaturized of Circularly Polarization Diversity at Cavity Backed SIW Antenna for X-Band Application." Frequenz 73, no. 9-10 (September 25, 2019): 317–20. http://dx.doi.org/10.1515/freq-2018-0230.

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Abstract In this work circularly polarization diversity has been achieved by utilizing two Schottky diodes on low profile cavity-backed substrate integrated waveguide (CBSIW). In comparison with other studies in the literature, the size of antenna has been reduced to 0.54λg × 0.76λg by helping a 50-Ohm coaxial feed line. The impedance bandwidth, axial ratio bandwidth and antenna gain are improved to 10.02 %, 5.2 % and 7.68dBi, respectively. In addition, the proposed antenna can generate either a left-hand circularly polarized (LHCP) or a right-hand circularly polarized (RHCP) radiation. The developed antenna was fabricated and tested and the achieved results were in good agreement with the simulated one.

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Stafeev, S. S. "An orbital energy flow and a spin flow at the tight focus." Computer Optics 45, no. 4 (July 2021): 520–24. http://dx.doi.org/10.18287/2412-6179-co-867.

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We have shown that a reverse energy flow (negative projection of the Poynting vector onto the optical axis) at the sharp focus of an optical vortex with topological charge 2 and left-hand circular polarization arises because the axial spin flow has a negative projection onto the optical axis and is greater in magnitude than positive projection onto the optical axis of the orbital energy flow (canonical energy flow). Also, using the Richards-Wolf formulas, it is shown that when focusing a left-handed circularly polarized light, in the region of the on-axis reverse energy flow, the light is right-handed circularly polarized.

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Zhou, Bin, Junping Geng, Zhe Li, Wenzhi Wang, Xianling Liang, and Ronghong Jin. "Dual Circularly Polarized Omnidirectional Antenna with Slot Array on Coaxial Cylinder." International Journal of Antennas and Propagation 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/127820.

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A dual circularly polarized (CP) omnidirectional antenna based on slot array in coaxial cylinder structure is presented in this paper. It is constructed by perpendicular slot pairs around and along the axis of the coaxial cylinder to realize the omnidirectional CP property, and two ports are assigned in its two sides as left hand circularly polarized (LHCP) port and right hand circularly polarized (RHCP) port, respectively. The proposed antenna achieves a bandwidth of 16.4% ranging from 5.05 to 5.95 GHz with an isolation higher than 15 dB between the two CP ports, and the return loss (RL) is higher than 10 dB within the bandwidth in both of the two ports. From the measured results, the average axial ratio (AR) of the proposed antenna in omnidirectional plane is lower than 1.5 dB.

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Kaur, Preet, and Pravin R. Prajapati. "Bilayer split-ring chiral metamaterial based reconfigurable antenna for polarization conversion." Frequenz 75, no. 9-10 (February 26, 2021): 357–68. http://dx.doi.org/10.1515/freq-2020-0182.

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Abstract A bilayer split-ring chiral metamaterial converts the linearly polarized wave, into a nearly perfect left or right-handed circularly polarized wave. The proposed antenna is intended to operate at center frequency of 5.80 GHz with switchable polarization capability. The polarization re-configurability is achieved by electronically switching of two PIN-diode pairs, which are embedded into bilayer split-ring Chiral Metamaterial. The optimized length of rectangular patch is 16 mm and width is 12.1 mm. Two types of radiation characteristics offered by the proposed antenna; left hand circularly polarized in mode 1 and right hand circularly polarized in mode 2. Measured results show that its impedance bandwidth is 155 MHz from 5.70 to 5.855 GHz for both mode 1 and mode 2. The measured axial-ratio bandwidth is 100 MHz from 5.75 to 5.85 GHz for mode 1 and 110 MHz from 5.73 to 5.84 GHz for mode 2. Antenna has LHCP gain of 2.52 dBi and RHCP gain of −23 dBi in mode 1. RHCP gain of 2 dBi and polarization purity of about −20 dBi is obtained in mode 2. The proposed antenna has simple structure, low cost and it has potential application in field of wireless communication (i.e., WiMax, WLAN etc.).

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Hematizadeh, A., S. M. Jazayeri, and B. Ghafary. "Generation of terahertz radiation by beating of two laser beams in collisional magnetized plasma." Laser and Particle Beams 34, no. 4 (August 30, 2016): 569–75. http://dx.doi.org/10.1017/s0263034616000513.

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AbstractThis paper presents analytical calculations for terahertz (THz) radiation by beating of two cosh-Gaussian laser beams in a density rippled collisional magnetized plasma. Lasers beams exert a ponderomotive force on the electrons of plasma in beating frequency which generates THz waves. The magnetic field was considered parallel to the direction of lasers which leads to propagate right-hand circularly polarized or left-hand circularly polarized waves in the plasma depending on the phase matching conditions. Effects of collision frequency, decentered parameter of lasers and the magnetic field strength are analyzed for THz radiation generation. By the optimization of laser and plasma parameters, the efficiency of order 27% can be achieved.

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15

Jun, Haeyoung, and Changdon Kee. "High Accuracy Pseudolite-based Navigation System: Compensating for Right-Hand Circularly Polarized Effect." Journal of Navigation 59, no. 2 (April 6, 2006): 307–20. http://dx.doi.org/10.1017/s0373463306003699.

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This paper presents further research on the SNUGL pseudolite-based navigation system presented in this journal in 2003. This system has centimetre-level accuracy, but has an error source arising from right-hand circularly polarized (RHCP) transmissions, unlike outdoor Global Positioning System (GPS). The GPS satellites and pseudolites use RHCP signals, and the polarization affects carrier-phase measurements according to the Line-of-Sight (LOS) vectors from transmitters to receivers. The RHCP error is eliminated by a double differencing process in outdoor GPS, but the error remains in the pseudolite-based system because the LOS vectors from transmitters to a reference and user receivers are different for the close transmitter constellations. This paper shows the RHCP effect on the pseudolite-based navigation system through simulations and experiments. It then shows the RHCP-compensation method improves the measurement and position accuracy by over 10%.

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Iqbal, Z., A. Hussain, G. Murtaza, and M. Ali. "On the damping of right hand circularly polarized waves in spin quantum plasmas." Physics of Plasmas 21, no. 12 (December 2014): 122118. http://dx.doi.org/10.1063/1.4904816.

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Squadrito, Paolo, Patrizia Livreri, Loreto Di Donato, Concetto Squadrito, and Gino Sorbello. "A Telemetry, Tracking, and Command Antennas System for Small-Satellite Applications." Electronics 8, no. 6 (June 18, 2019): 689. http://dx.doi.org/10.3390/electronics8060689.

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Circularly polarized (CP) antennas are used in space applications for telemetry tracking and command (TT&C). In this paper, we present an antenna for a TT&C system that can employ only four antennas to achieve a wide quasi-isotropic coverage. The proposed single-feed circular polarized annular patch antenna is low profile and compact. It exhibits a wide impedance bandwidth of 19.7%, wide-angle circular polarization with an on-axis maximum gain higher than 6 dBi and an axial ratio below 4 dB in the frequency band 2.0–2.3 GHz. The developed low-cost antenna can be used for small-satellite data downlink where only two right hand circular polarized (RHCP) antennas and two left hand circular polarized (LHCP) antennas would be required since each antenna has an adequate CP gain on a wide angle. A prototype antenna has been fabricated and measured. The experimental validation shows a good agreement of the measured impedance bandwidth, axial ratio, and far-field pattern with the ones predicted by numerical full-wave study.

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Gnavi, G., L. Gomberoff, F. T. Gratton, and R. M. O. Galvão. "Electromagnetic ion-beam instabilities in a cold plasma." Journal of Plasma Physics 55, no. 1 (February 1996): 77–86. http://dx.doi.org/10.1017/s0022377800018675.

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We study the stability of the cold-plasma dispersion relation for circularly polarized waves in a plasma composed of an ion background and an ion beam. The presence of the beam introduces a resonant branch into the dispersion relation for right-hand-polarized waves propagating in the direction of the external magnetic field, which, for V>Vφ, has negative energy (here V is the beam velocityVφ is the wave phase velocity). Therefore this branch may give rise to explosive instabilities when the waves experience parametric decays. It is shown graphically that resonant right-hand-polarized and non-resonant left-hand-polarized waves, propagating parallel to the external magnetic field, can be unstable. It is also shown that the instability region can extend to large frequencies and wavenumnbers, and that the instability regions have a band structure. The parametric dependence of instability thresholds and marginal modes is also studied.

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Kawdungta, Supakit, and Chuwong Phongcharoenpanich. "Circularly polarized reconfigurable microstrip loop antenna using parasitic patches and PIN diodes." Frequenz 74, no. 7-8 (July 28, 2020): 255–62. http://dx.doi.org/10.1515/freq-2019-0160.

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AbstractThis research proposes a novel circularly polarized (CP) reconfigurable microstrip loop antenna for 2.4–2.5 GHz advanced wireless communication using two parasitic patches and two PIN diodes. The reconfigurable antenna can alternate between right hand circular polarization (RHCP) and left hand circular polarization (LHCP) at the main beam by manipulating the ON/OFF status of the PIN diodes. Simulations were carried out for the optimal antenna parameters, and an antenna prototype was fabricated and experiments were undertaken. The simulation and measured results are in good agreement. The antenna achieves an impedance bandwidth of 2.4–2.5 GHz and unidirectional radiation pattern with a maximum gain of 5 dBic and 3-dB axial ratio for both RHCP and LHCP. As a result, the proposed reconfigurable antenna could be utilized to improve wireless communication performance. In essence, the novelty of this research lies in the utilization of parasitic patches and shorted PIN diodes to transform linear to circular polarization; and the reconfigurability of polarization between RHCP and LHCP.

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Parihar, Manoj S., Ananjan Basu, and Shiban K. Koul. "Transient analysis of reconfigurable polarization antenna." International Journal of Microwave and Wireless Technologies 5, no. 4 (February 18, 2013): 521–27. http://dx.doi.org/10.1017/s175907871300007x.

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Time-domain characterization of a microstrip patch antenna with circular corner truncation to achieve polarization reconfigurability is presented. By applying zero bias, forward bias, and reverse bias to the four PIN diodes, the antenna can radiate with linear polarization (LP), right hand circular polarization (RHCP), and left hand circular polarization (LHCP). The circular cuts reduce centre-frequency shift from linear to circularly polarized states, compared with conventional straight cuts. Time-domain simulation and measurement are carried out to show the switching characteristics of the proposed antenna, and it is established that satisfactory switching speed can be obtained using a simple low-cost driver circuit.

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Le, Tu, Han-Young Park, and Tae-Yeoul Yun. "Simple Reconfigurable Circularly Polarized Antenna at Three Bands." Sensors 19, no. 10 (May 20, 2019): 2316. http://dx.doi.org/10.3390/s19102316.

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In this paper, a simple design for a triple-band circularly polarized (CP) antenna with the capability of switching its polarization between dual-sense CPs is presented. The proposed antenna is comprised of a monopole loop antenna as a primary radiator. By placing a parasitic loop around the primary radiator, an additional CP band is achieved. Reconfigurability of the polarization between right-hand CP (RHCP) and left-hand CP (LHCP) at three different frequencies of 2.5, 3.3, and 3.8 GHz was realized by controlling the ON/OFF states of two PIN diodes. For validation, the fabricated antenna yielded an impedance bandwidth of 52.6% (2.34–4.01 GHz), while the axial ratio bandwidths for both the RHCP and LHCP states were 3.5% (2.47–2.56 GHz), 6.6% (3.20–3.42 GHz), and 2.4% (3.74–3.83 GHz). The measured broadside gains within the axial ratio bandwidth were 1.2, 2.7, and 1.4 dBi, respectively. Compared to other reconfigurable multi-band CP antennas, the proposed design is the first work to achieve a reconfigurable polarization at three distinct bands at a low fabrication cost by using only two diodes. The proposed antenna is suitable for WLAN and WiMAX applications.

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RUDERMAN, MICHAEL S., and PHILIPPE CAILLOL. "Parametric instabilities of circularly polarized small-amplitude Alfvén waves in Hall plasmas." Journal of Plasma Physics 74, no. 1 (February 2008): 119–38. http://dx.doi.org/10.1017/s0022377807006691.

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AbstractWe study the stability of circularly polarized Alfvén waves (pump waves) in Hall plasmas. First we re-derive the dispersion equation governing the pump wave stability without making anad hocassumption about the dependences of perturbations on time and the spatial variable. Then we study the stability of pump waves with small non-dimensional amplitudea(a≪ 1) analytically, restricting our analysis tob< 1, wherebis the ratio of the sound and Alfvén speed. Our main results are the following. The stability properties of right-hand polarized waves are qualitatively the same as in ideal MHD. For any values ofband the dispersion parameter τ they are subject to decay instability that occurs for wave numbers from a band with width of ordera. The instability increment is also of ordera. The left-hand polarized waves can be subject, in general, to three different types of instabilities. The first type is the modulational instability. It only occurs whenbis smaller than a limiting value that depends on τ. Only perturbations with wave numbers smaller than a limiting value of orderaare unstable. The instability increment is proportional toa2. The second type is the decay instability. It has the same properties as in the case of right-hand polarized waves; however, it occurs only whenb< 1 τ. The third type is the beat instability. It occurs for any values ofband τ, and only perturbations with the wave numbers from a narrow band with the width of ordera2are unstable. The increment of this instability is proportional toa2, except for τ close to τcwhen it is proportional toa, where τcis a function ofb.

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Istomin, Ya N. "On the Nature of the Circularly Polarized Component of Pulsar Radio Emission." International Astronomical Union Colloquium 128 (1992): 375–77. http://dx.doi.org/10.1017/s0002731600155568.

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AbstractIt is shown that circular polarization occurs in the region of cyclotron resonance because the group velocities of right-hand and left-hand polarized waves are different with respect to the direction of the magnetic field. Due to the dependence of the intensity of radio emission on the coordinates across the polar cap, this difference in group velocities leads to noncompensated circular polarization proportional to the derivative of the total intensity as a function of longitude. The indicated dependence corresponds to observations of the so-called core component of pulsar radio emission.

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Edy Purnomo, Muhammad Fauzan, and Akio Kitagawa. "Triangular Microstrip Antenna for Circularly-Polarized Synthetic Aperture Radar Sensor Application." Indonesian Journal of Electrical Engineering and Computer Science 12, no. 1 (October 1, 2018): 310. http://dx.doi.org/10.11591/ijeecs.v12.i1.pp310-318.

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<p>In this paper, we obtain the basic construction of triangular microstrip antennas based on the analysis of the single patch and array two patches. This construction use the basic corporate feeding-line with modified lossless T-junction power divider for Circularly Polarized-Synthetic Aperture Radar (CP-SAR) sensor embedded on airspace with compact, small, and simple configuration. The design of Circular Polarization (CP) is realized by truncating the whole three tips and adjusted the parameters of antennas at the resonant frequency, f = 1.25 GHz. The equations for reciprocal, lossless, and matched of the modified lossless T-junction power divider are also described. The result of characteristic performance and S-parameter for the single patch both Left-Hand Circular Polarization (LHCP) and Right-Hand Circular Polarization (RHCP) at the resonant frequency show consecutively 7.15 dBic and 7.16 dBic of gain, 0.12 dB and 0.11 dB of axial ratio, -26.75 dB and -26.72 dB of S-parameter. For array two patches, the result of gain, axial ratio, and S-parameter both of LHCP and RHCP are 7.63 dBic, 7.62 dBic, 2.68 dB, 2.74 dB, -19.43 dB, and -19.40 dB, respectively. The modified lossless T-junction power divider both for LHCP and RHCP are capable of being reciprocal, matched, and lossless at all ports.</p>

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Kumar, Arun, Santanu Dwari, Ganga Prasad Pandey, Binod Kumar Kanaujia, and Dinesh Kumar Singh. "A high gain wideband circularly polarized microstrip antenna." International Journal of Microwave and Wireless Technologies 12, no. 7 (February 4, 2020): 678–87. http://dx.doi.org/10.1017/s1759078719001612.

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AbstractIn this paper, a high gain wideband circularly polarized (CP) microstrip antenna is presented for broadband operation. The proposed structure comprised of a partially grounded printed monopole antenna loaded with a split ring resonator and a metallic reflector. By using the metallic reflector surface underneath the patch radiator results in the reflected waves in the same phase with main lobe radiation, thereby improving the gain and it also acts like a secondary radiator to generate wideband CP behavior in the proposed design. A gain enhancement of 4.3 dBi is achieved in the operating frequency band as compared with the design without a metallic reflector. The maximum gain achieved in the presented method is 8.6 dBic over the entire operating range. The proposed design shows a wideband behavior ranging from 4.30 to 9.10 GHz with the 10-dB impedance bandwidth of 71.64%. In addition, the proposed design yielded a broadside right hand CP radiation with a 3-dB axial ratio bandwidth of 33.88% from 4.98 to 7.01 GHz. The proposed antenna is fabricated and experimental results on reflection coefficient, gain, axial ratio, and radiation patterns concede well with simulation results.

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Dr. V. Prakasam and Dr. P. Sandeep. "Dual Edge-Fed Left Hand and Right Hand Circularly Polarized Rectangular Micro-Strip Patch Antenna for Wireless Communication Applications." IRO Journal on Sustainable Wireless Systems 2, no. 3 (November 25, 2020): 107–17. http://dx.doi.org/10.36548/jsws.2020.3.001.

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Presently a days the remote correspondence framework advancement requires the ease, low profile, insignificant weight radio wire improvement which is cultivated of proceeding with incredible introduction finished a wide recurrence range. The MSPA architecture has facilitated this forward thinking skills trend. Within this paper work a 4.85 GHz circular polarization operating frequency is planned and simulated for RMSPA. The proposed antenna is capable of designing and inducing Left Hand Loop Polarization (LHCP) and Right Hand Loop Polarization (RHCP) using a cross-coupler that is directly attached to the micro-strip antenna to polarize the circular. The proposed paper work working recurrence is 4.85 GHz which is essentially utilized for satellite interchanges, full-time satellite TV organizations. This working recurrence is the IEEE 802.11a variation C band recurrence and this C band recurrence is utilized in Wi-Fi gadgets and Radio LAN. The proposed FR-4 roundabout polarization rectangular miniature strip fix radio wire is 1.6 mm thick. The proposed rectangular micro strip fix radio wire is planned and mimicked utilizing CSTMWS (Computer Simulation Technology Micro Wave Studio) programming. The full or working recurrence of proposed radio wire presents at 4.85 GHz for remote correspondences that gives S boundaries, data transmission and radiation example of Gain and directivity.

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Pavone, Santi Concetto, Giorgio Sebastiano Mauro, Loreto Di Donato, and Gino Sorbello. "Design of Dual Circularly Polarized Sequentially-Fed Patch Antennas for Satellite Applications." Applied Sciences 10, no. 6 (March 20, 2020): 2107. http://dx.doi.org/10.3390/app10062107.

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In this paper, we present the design and fabrication of two dual circularly polarized (CP) patch antennas that can be profitably used as feeders for reflector systems normally adopted for satellite applications. In the first part of the manuscript, we propose the optimization of a dual-CP patch antenna, loaded by a fence of passive monopoles around it to increase antenna gain for high elevation angles. To achieve dual-CP operation mode, the circular patch has been sequentially-fed by three pins, whose mutual phase-shift is equal to 120 ∘ . The antenna feeding network was placed on the antenna back and designed using microstrip technology. Two different input ports provide both right-hand (RH) and left-hand (LH) circular polarizations. A prototype of such an antenna was fabricated and measured at f = 8 . 25 GHz. Furthermore, to test the versatility of the proposed single radiating patch, in the second part of the manuscript, we present the results of geometrically scaling at f = 2 . 2 GHz (higher UHF band) and this was used as a building block for the design of a dual-CP sequentially-fed 2-by-2 array antenna. The results for both the proposed antennas are satisfactory in terms of impedance bandwidth, broad radiation pattern, gain and cross-polarization rejection, thus they can be profitably used as feeders for reflectors at relatively low frequencies.

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N, Likith, Gayathri K M, Thusshara S, Maria Sanjeetha, and Thangadurai N. "Design & Analysis of S-Band Right Hand Circularly Polarized Conical Horn Antenna for NavIC Receiver." International Journal of Engineering & Technology 7, no. 3.12 (July 20, 2018): 512. http://dx.doi.org/10.14419/ijet.v7i3.12.16169.

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In satellite communication systems the horn antennas are being used widely due to its robustness and capable to operate at frequencies which are very high. Here, the right hand circular polarized conical horn antenna is designed for S-band NavIC receiver. The waveguides and conical horn antenna dimensions are designed by using standard formulas and after that they are given to a simulation tool for the S band frequency. The performance parameters like return loss, radiation pattern, gain and directivity are considered for further analysis. In the circular waveguide from the TE11 mode conical horn antenna is to be designed into high gain and a good VSWR.

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Javan, N. Sepehri, and M. Hosseinpour Azad. "Thermal behavior change in the self-focusing of an intense laser beam in magnetized electron-ion-positron plasma." Laser and Particle Beams 32, no. 2 (April 11, 2014): 321–30. http://dx.doi.org/10.1017/s0263034614000184.

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AbstractSelf-focusing of an intense circularly-polarized laser beam in a hot electron-positron-ion magneto-plasma is studied. Using a relativistic fluid model, nonlinear equation describing laser-plasma interaction in the quasi-neutral approximation is derived. Expanding nonlinear current density in terms of normalized vector potential and saving only the parabolic terms, we investigated the self-focusing phenomenon for right- and left-hand circularly polarized laser beams. The evolution of laser beam spot size with Gaussian profile is considered. Effects of the external magnetic field, fraction of electron-positron pairs, and also the kind of polarization on the self-focusing property are studied. It is shown that a mixture of electron-positron pairs to the ion-electron plasma modifies the behavior of plasma with respect to the external magnetic field.

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Kumar, Sachin, Gwan Hui Lee, Dong Hwi Kim, Hyun Chul Choi, and Kang Wook Kim. "Dual Circularly Polarized Planar Four-Port MIMO Antenna with Wide Axial-Ratio Bandwidth." Sensors 20, no. 19 (September 30, 2020): 5610. http://dx.doi.org/10.3390/s20195610.

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A broadband compact-sized planar four-port multiple-input–multiple-output (MIMO) antenna with polarization diversity is presented. The proposed dual circularly polarized (CP) MIMO antenna consists of four G-shaped monopole elements, two of which are left-hand CP and the other two are right-hand CP. A vertical line strip in the G-shaped radiating element acts in balancing the vertical and horizontal electric field components to obtain 90° phase difference between them for circular polarization. Also, an I-shaped strip is incorporated between the ground planes of the G-shaped antenna elements to obtain equal voltage level in the proposed MIMO configuration. The dual circular polarization mechanism of the proposed MIMO/diversity antenna is analysed from the vector current distributions. The impedance bandwidth (S11 ≤ –10 dB) of the MIMO antenna is 105.9% (4–13 GHz) and the 3 dB axial ratio bandwidth (ARBW) is 67.7% (4.2–8.5 GHz), which is suitable for C-band applications. The overall size of the MIMO antenna is 70 × 68 × 1.6 mm3, and the minimum isolation between the resonating elements is 18 dB. The envelope correlation coefficient is less than 0.25, and the peak gain within the resonating band is 6.4 dBi.

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Zeng, Xiaoyong, Kama Huang, Zhongxia Hu, Qian Chen, and Wei Xiao. "A Circularly Polarized HTS Microstrip Antenna Array with Controllable Cryostat." International Journal of Antennas and Propagation 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/6035202.

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A high-temperature superconductor (HTS) microstrip antenna array with right-hand circular polarization is proposed for space communications. The proposed HTS antenna array can achieve high efficiency, which is able to reduce the antenna’s loss. The array consists of 16 antenna elements being fed by a T-network. A pair of symmetric meander slots is used in each antenna element to broaden the input matching bandwidth. A controllable cryostat is used as the refrigeration for HTS. The experiment shows that the gain of the proposed HTS antenna is 8.39 dB, whose 10 dB return loss bandwidth is 2.2% ranging from 5.75 GHz to 5.87 GHz. In comparison with a traditional conductor antenna array having the same configuration, the proposed array has an 8.1 dB improvement in the gain and a 69.2% enhancement in the radiation efficiency.

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Wang, Li, Chang-liang Zhao, Rui Zhang, Xi Chen, Guang Fu, and Xiao-wei Shi. "Wideband Circularly Polarized Ellipse Antenna Array with Gain Enhancement." International Journal of Antennas and Propagation 2018 (September 17, 2018): 1–12. http://dx.doi.org/10.1155/2018/3158365.

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In this paper, a wideband circularly polarized (CP) antenna element and array with gain enhancement are presented. The original antenna element adopts two orthogonal ellipse dipoles with end-loading pillars. In order to achieve a wide impedance bandwidth (IBW), a harpoon-shaped feed patch (HSFP) as electromagnetic coupling-feed is utilized. By introducing a coupled frame and a loop cavity, the gain of the element is crucially improved. Then, four sequentially rotated elements placed in a circular contour act as 2 × 2 array, and a similar loop metal cavity is employed to the array to reach gain enhancement. For the wideband CP performance of the proposed antenna, a wideband phase shifting feed network (WPSFN) is used to construct the antenna. Finally, to verify the feasibility of the proposed antenna, a prototype array is manufactured and measured. Experimental results are found in acceptable agreement with the simulated ones in terms of gain, radiation efficiency, radiation pattern, reflection coefficient, and axial ratio (AR). The result indicates that the proposed antenna has an IBW for reflection coefficient S11 ≤ − 10 dB of 85.7% (0.80–2.00 GHz). Moreover, benefit from the sequentially rotated technique (SRT), the AR at broadside direction keeps blow 3 dB during the overlapped bandwidth of S11≤ − 10 dB, and the ARBW for AR ≤ 1 dB of 74.4% (0.85–1.78 GHz) can be achieved. By employing the loop cavity, the right hand circularly polarization (RHCP) gain is significantly improved, which keeps above 10.00 dBic from 1.05 GHz to 1.85 GHz, and the peak gain reaches to 13.91 dBic.

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Cheng, Lin, Xiaomingliang Li, Zelong Wang, Pengfei Cao, Xiaodong He, and Tiaoming Niu. "AdjusTable 3D Plasmonic Archimedes Spiral Lens for Optical Manipulation." Applied Sciences 9, no. 4 (February 16, 2019): 674. http://dx.doi.org/10.3390/app9040674.

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A novel adjustable three-dimensional plasmonic Archimedes spiral lens (3D PASL) has been investigated and analyzed in detail by numerical simulations. The 3D PASL consists of a spiraling Archimedes helix slot that is engraved on the inner wall of a funnel-shaped gold film on a silicon dioxide substrate. When the incident light from the bottom of substrate is composed of left-hand circularly polarized (LCP) waves, the transmitted light field will converge completely to a focused point that floats in the hollow funnel. This light field will change into an optical vortex when the incident light is changed to right-hand circularly polarized (RCP) waves. The performance of our 3D PASL is discussed for particle trapping or rotation applications. In addition, the position of the optical focus or vortex can be adjusted by varying the height of the structure. Our 3D PASL is highly flexible for practical optical manipulation applications and overcomes the problem where the previous two-dimensional PASL could only manipulate particles on the surface.

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Huang, Jiayao, Zijie Liang, Fu Deng, Weihao Yu, Ruihuang Zhao, Bo Chen, Xiangbo Yang, and Dongmei Deng. "Propagation properties of right-hand circularly polarized Airy–Gaussian beams through slabs of right-handed materials and left-handed materials." Journal of the Optical Society of America A 32, no. 11 (October 19, 2015): 2104. http://dx.doi.org/10.1364/josaa.32.002104.

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Saravanan, Manavalan, and Madihally Janardhana Srinivasa Rangachar. "Design of Rhombus-Shaped Slot Patch Antenna for Wireless Communications." Journal of Computer Networks and Communications 2019 (January 10, 2019): 1–7. http://dx.doi.org/10.1155/2019/5149529.

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A single feed circularly polarized patch antenna is presented. The antenna consists of a rhombus-shaped slot incorporated in the radiating patch at its center. The antenna is designed to operate at 2.3 GHz band. The antenna achieves left-hand polarization or right-hand polarization based on the orientation of the slot in the radiating patch. The antenna parameters are synthesized using a high-frequency structure simulator and its characteristics are validated by the Agilent network analyzer (N9925A) and antenna test systems. The measured results obtained agree with simulated results and show that the antenna achieves −10 dB impedance bandwidth of 85 MHz (2.27 GHz–2.355 GHz) for left-hand polarization and 85 MHz (2.26 GHz–2.345 GHz) for right-hand polarization. The antenna gives a 3 dB axial ratio beamwidth of 95°(−35° ≤ AR ≤ 60°) for both left-hand polarization and right-hand polarization along with better 3 dB axial ratio bandwidth of 140° in the operating band. The antenna also achieves a good cross-polarization isolation of −17 dBic for both left-hand and right-hand polarization at its operating frequency. Hence, the antenna is best suited for modern wireless communication systems.

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Florencio, Rafael, Daniel Martinez-de-Rioja, Eduardo Martinez-de-Rioja, Jose A. Encinar, Rafael R. Boix, and Vicente Losada. "Design of Ku- and Ka-Band Flat Dual Circular Polarized Reflectarrays by Combining Variable Rotation Technique and Element Size Variation." Electronics 9, no. 6 (June 12, 2020): 985. http://dx.doi.org/10.3390/electronics9060985.

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In this work circularly polarized flat reflectarray antennas are designed to work at downlink frequencies in Ku- and Ka-band. The design approach for circular polarization radiation combines both the variable rotation technique (VRT) and the element size variation technique (ESVT). The reflectarray element employed consists of a rotable split ring operating at 12 GHz (Ku-band) that surrounds two orthogonal sets of parallel dipoles of variable size operating at 20 GHz (Ka-band). Rotations of split rings and different sizes of dipoles are exploited as degrees of freedom by VRT and ESVT for designing focused beams dual band dual circular polarized reflectarrays. The split ring can be used to achieve single focused beams for circular polarization by VRT at 12 GHz, and the set of orthogonal dipoles can be used to achieve two focused beams for dual circular polarization by ESVT at 20 GHz. In this way, the reflectarray element has been used to design two flat dual band circularly polarized reflectarrays that generate three pencil beams either in the same direction or in different directions: one pencil beam with right-hand circular polarization (RHCP) at 12 GHz and two pencil beams with both RHCP and left-hand circular polarization (LHCP) at 20 GHz. The designed reflectarrays are carried out under local periodicity assumption by means of in-house electromagnetic software that applies the Method of Moments in the Spectral Domain. Validations of the in-house electromagnetic software show significant CPU time savings with respect to CPU time consumption provided by commercial software of general purpose as CST electromagnetics software. Numerical results of radiation patterns produced by the designed reflectarrays show efficiencies around 65% and a bandwidth of 6% for a main beam cross-polarization discrimination of 25 dB. The numerical results are satisfactorily validated by CST software and a tolerance errors study has been numerically carried out with acceptable results.

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Verkhoglyadova, O. P., and B. T. Tsurutani. "Polarization properties of Gendrin mode waves observed in the Earth's magnetosphere: observations and theory." Annales Geophysicae 27, no. 12 (December 4, 2009): 4429–33. http://dx.doi.org/10.5194/angeo-27-4429-2009.

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Abstract. We show a case of an outer zone magnetospheric electromagnetic wave propagating at the Gendrin angle, within uncertainty of the measurements. The chorus event occurred in a "minimum B pocket". For the illustrated example, the measured angle of wave propagation relative to the ambient magnetic field θkB was 58°±4°. For this event the theoretical Gendrin angle was 62°. Cold plasma model is used to demonstrate that Gendrin mode waves are right-hand circularly polarized, in excellent agreement with the observations.

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38

Zang, XiaoFei, BingShuang Yao, Zhen Li, Yang Zhu, JingYa Xie, Lin Chen, Alexey V. Balakin, Alexander P. Shkurinov, YiMing Zhu, and SongLin Zhuang. "Geometric phase for multidimensional manipulation of photonics spin Hall effect and helicity-dependent imaging." Nanophotonics 9, no. 6 (June 6, 2020): 1501–8. http://dx.doi.org/10.1515/nanoph-2020-0115.

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AbstractThe spin Hall effect of light, associated with spin-orbit interactions, describes a transport phenomenon with optical spin-dependent splitting, leading to a plethora of applications such as sensing, imaging, and spin-controlled nanophotonics. Although geometric meatsurfaces can mimic photonic spin Hall effect by spatially splitting left-hand circularly polarized and right-hand circularly polarized states of electromagnetic waves with anomalous refraction or reflection angles, the geometric phase generated by metasurfaces hinders metalenses to realize simultaneous focusing of different spin states, limiting further applications. Here, we propose and experimentally demonstrate an approach to realizing a spin Hall metalens that can focus terahertz waves with different spin states and flexibly manipulate spin-dependent focal points in multiple spatial dimensions based on a pure geometric phase. A dielectric metasurface consisting of micropillars with identical shape and different in-plane orientations is designed to realize the multidimensional manipulation of photonics spin Hall effect in terahertz region. Furthermore, helicity-dependent imaging is demonstrated by the terahertz spin Hall metalens. The uniqueness and robust approach for manipulating spin photons may have a significant impact on designing ultra-compact and multifunctional devices and spin photonics devices.

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39

Mu, Zhuo, Shen-Yun Wang, and Wen-Ying Meng. "A Wideband Polarization Reconfigurable Antenna Array Based on Mode Combination Method." Frequenz 73, no. 5-6 (May 27, 2019): 153–59. http://dx.doi.org/10.1515/freq-2018-0235.

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Abstract This paper reports a novel polarization-reconfigurable antenna array based on the theory of mode combination (MC), which can electronically alter its polarization states between left-hand circular polarization (LCP) mode, right-hand circular polarization (RCP) mode, and two combined linear polarization (LP) modes. The array element is adopted as the L-probes fed circularly-polarized antenna reported by Luk et al. [1]. To verify the concept, a prototype of 2×2 antenna array is manufactured and tested. By properly exciting the feeding probes, four polarization modes can be switchable. Measurement results show that the proposed antenna has an overlapped −10 dB impedance bandwidth around 34 % for both CP modes and LP(2) mode, and an overlapped 3 dB axial-ratio bandwidth around 22.0 % of the CP modes. The average realized gains are around 12.4 dB for CP modes and LP(1) mode, which remain stable in the axial-ratio bandwidth.

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40

GHANASHEV, I., I. ARESTOVA, E. TATAROVA, I. ZHELYAZKOV, and Sv STOYKOV. "Dispersion of dipolar electromagnetic waves in a radially inhomogeneous axially magnetized plasma column." Journal of Plasma Physics 58, no. 4 (December 1997): 633–46. http://dx.doi.org/10.1017/s0022377897005953.

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The wavelengths and attenuation coefficients of dipolar left and right-hand circularly polarized waves in a radially inhomogeneous axially magnetized plasma column are computed by means of step approximation of the radial plasma density profile. A comparison with theoretical results assuming radial plasma homogeneity shows that the radial plasma inhomogeneity is significant for wave propagation. In particular, it facilitates the occurrence of backward waves and increases by up to one order of magnitude the wave attenuation coefficient compared with a homogeneous plasma column having the same average plasma density.

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41

Sepehri Javan, Nasser, and Ramin Roozehdar Mogaddam. "Self-focusing of linearly-polarized laser beam in the semi-bounded magnetized warm plasma: competition of right- and left-hand circularly-polarized modes." Plasma Physics and Controlled Fusion 62, no. 11 (September 30, 2020): 115010. http://dx.doi.org/10.1088/1361-6587/abb217.

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42

Liu, Yuan-zhu, Shao-qiu Xiao, and Bing-zhong Wang. "A RHCP Microstrip Antenna with Ultrawide Beamwidth for UHF Band Application." International Journal of Antennas and Propagation 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/472397.

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A novel right-hand circularly polarized (RHCP) UHF microstrip antenna with 3 dB beamwidth of more than 150° is presented in this paper. The 3 dB RHCP beamwidth can be broadened by utilizing a combined ground structure with a hollow truncated cone ground plane and a metallic rectangular plate. Optimizing the half-angleθcof cone and the cone heighthcone, a 3 dB RHCP beamwidth of more than 200° can be acquired, which is about 120° greater than its corresponding regular RHCP microstrip antenna. There is a good agreement between the measured results and simulated results for the proposed antenna operating in UHF band.

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43

SHUKLA, P. K., R. BINGHAM, A. D. R. PHELPS, and L. STENFLO. "Dark and grey electromagnetic electron-cyclotron envelope solitons in an electron-positron magnetoplasma." Journal of Plasma Physics 75, no. 5 (October 2009): 575–80. http://dx.doi.org/10.1017/s0022377809990092.

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AbstractWe present an investigation of the amplitude modulation of an external magnetic field-aligned right-hand circularly polarized electromagnetic electron-cyclotron (EMEC) wave in a strongly magnetized electron-positron plasma. It is shown that the dynamics of the modulated EMEC wave packet is governed by a cubic nonlinear Schrödinger equation. The latter reveals that a modulated wave packet can propagate in the form of either a dark or a grey envelope soliton. This result could have relevance to the transport of electromagnetic wave energy over long distances via envelope solitons in the magnetospheres of pulsars and magnetars.

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44

Zhang, Yan, Da Sun, Tao Dong, and Jie Yin. "Design of Reconfigurable Patch Antenna in Frequency, Pattern, and Switchable Polarization." Applied Computational Electromagnetics Society 35, no. 9 (November 4, 2020): 1037–46. http://dx.doi.org/10.47037/2020.aces.j.350909.

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In this paper, a circularly polarized frequency, pattern, and polarization switching antenna is proposed. The antenna consists of an octagonal patch, a narrow octagonal ring and four diamond-shaped parasitic patches on the top layer. Two feed points of the radiating patch are connected to a Wilkinson power divider loaded with the phase reconfigurable transmission lines on the bottom layer. Reconfiguration of the polarization and pattern is realized by using PIN diodes as switching components. By controlling the bias voltage across the varactors, various narrow frequency bands can be achieved. The proposed antenna operates at a frequency tuning range from 1.96 to 2.03 GHz. The radiation pattern can be switched among five cases in yoz-plane and xoz-plane, with the switchable polarization between left- and right-hand circular polarization. In addition, these three types of reconfiguration can be controlled independently.

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45

Qasaymeh, Yazeed M. I. "Design and Impedance Modeling of a Compact Sequentially Rotated Quasi-Lumped Antenna Array for Wi-Fi Applications." International Journal of Antennas and Propagation 2021 (September 18, 2021): 1–10. http://dx.doi.org/10.1155/2021/3874794.

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In this study, a miniaturized 2 × 2 sequentially rotated (SR), circularly polarized (CP), and quasi-lumped antenna array that resonates in the IEEE 802.11a band is introduced. The shorting pins technique is implemented to achieve circular radiation patterns, and the resonating elements are excited using a SR quarter-wavelength feeding network. A resonance model of the four radiating elements array is postulated to give a physical insight into the relative dimensions and to allow for a study of the resonance characteristics and the effect of the shorting pins. An antenna model is simulated, fabricated, and measured to authenticate this arrangement, giving results of |S11| < −10 dB and axial ratio (AR) < 3 dB for bandwidths of 3.85% (5.645–5.867 GHz) and 1.54% (5.77–5.86 GHz) for right-hand circular polarization (RHCP). The size of the antenna array structure is 0.696 λ 0 × 0.599 λ 0 × 0.0157 λ 0 at a center frequency of 5.8 GHz.

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Priya, Anumuthu, S. Kaja Mohideen, and Manavalan Saravanan. "Design of Polarization Reconfigurable Patch Antenna for Wireless Communications." Applied Computational Electromagnetics Society 35, no. 8 (October 7, 2020): 893–98. http://dx.doi.org/10.47037/2020.aces.j.350807.

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A single fed circularly polarized reconfigurable patch antenna is proposed. The antenna consists of a radiating patch incorporated with an H-shaped slot at its center. Four ultra-miniature switches are used for polarization reconfiguration. The antenna is designed to operate at the center frequency of 2.357 GHz. The antenna achieves either left-hand polarization or right-hand polarization depending upon switching of corresponding switches. The antenna parameters are simulated using Ansoft high-frequency structure simulator and are validated using an Agilent network analyzer (N9925A) and antenna test systems. The antenna achieves a good impedance match of 120MHz between 2.26GHz – 2.38GHz band and achieves low cross-polarization isolation of -22.82 dB for RHCP and -21.77 dB for LHCP configurations at its operating frequency. The antenna finds application in areas of modern wireless communication.

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Agneessens, Sam, Patrick Van Torre, Frederick Declercq, Bart Spinnewyn, Gert-Jan Stockman, Hendrik Rogier, and Dries Vande Ginste. "Design of a Wearable, Low-Cost, Through-Wall Doppler Radar System." International Journal of Antennas and Propagation 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/840924.

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A novel, low-cost, low-weight, wearable Doppler radar system composed of textile materials and capable of detecting moving objects behind a barrier is presented. The system operates at 2.35 GHz and is integrable into garments, making it well-suited for usage in difficult to access terrain, such as disaster areas or burning buildings. Wearability is maximized by relying on flexible, low-weight, and breathable materials to manufacture the key parts of the system. The low-complexity Doppler radar system makes use of an array of four textile-transmit antennas to scan the surroundings. The beam emitted by this array is right-hand circularly polarized along all scanning angles and provides a measured gain of 9.2 dBi. At the receiving end, textile materials are used to develop an active wearable receive antenna, with 15.7 dBi gain, 1.1 dB noise figure, left-hand circular polarization, and a 3 dB axial ratio beamwidth larger than 50°. Several measurement setups demonstrate that the onbody system is capable of detecting multiple moving subjects in indoor environments, including through-wall scenarios.

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Yang, Peng-Ju, Rui Wu, Xincheng Ren, and Yuqiang Zhang. "DOPPLER SPECTRUM OF SCATTERED WAVE FROM TWO-DIMENSIONAL TIME-VARYING NONLINEAR SEA SURFACES UNDER RIGHT-HAND CIRCULARLY POLARIZED WAVE INCIDENCE." Progress In Electromagnetics Research B 84 (2019): 61–77. http://dx.doi.org/10.2528/pierb19012001.

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Ha, Jaegeun, Mohamed A. Elmansouri, Prathap Valale Prasannakumar, and Dejan S. Filipovic. "Monostatic Co-Polarized Full-Duplex Antenna With Left- or Right-Hand Circular Polarization." IEEE Transactions on Antennas and Propagation 65, no. 10 (October 2017): 5103–11. http://dx.doi.org/10.1109/tap.2017.2741064.

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Fleck, B., F. L. Deubner, and W. Schmidt. "Observations of Waves and Oscillations in the Solar Magnetic Fine Structure." International Astronomical Union Colloquium 141 (1993): 522–25. http://dx.doi.org/10.1017/s0252921100029754.

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AbstractWe study the oscillatory behaviour of small-scale magnetic flux-tube concentrations and their immediate surroundings by analysing high spatial resolution time series of spectra of four Zeeman sensitive lines (Fe I 5247.1, Cr I 5247.6, Fe I 5250.2, Fe I 5250.7) taken simultaneously in left-hand and right-hand circularly polarized light with the Echelle spectrograph at the Vacuum Tower Telescope in Izaña, Tenerife. The velocity field inside the magnetic elements is dominated by the 5-min oscillations which also show up as periodic variations in the relative amplitude asymmetry of the Stokes V profiles. In other parameters as for instance the Stokes V peak separation we cannot detect an oscillatory component. Neither the magnetic line ratio nor the thermal line ratio is affected by the 5-min oscillations, although the latter reveals remarkable spatiotemporal variations.

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Journal articles on the topic 'Right hand circularly polarized'

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