scholarly journals Method of Averaged Lagrangian for Precessional Rotation and Other Complementary Effects of Waves in Nonlinear Plasmas

1983 ◽  
Vol 36 (6) ◽  
pp. 867
Author(s):  
B Chakraborty ◽  
SN Paul

The formalism of the averaged Lagrangian has been extended and developed to evaluate the intensitydependent precessional rotation and wave number shift of an elliptically polarized electromagnetic wave in unmagnetized cold relativistic plasmas; the results are identical to those of Arons and Max (1974) and others. Moreover, the expression for two intensity-induced nonlinear modulation frequencies for both the right and left circular polarization components of the wave have been derived. The mathematical technique developed here may be useful in the study of other types of nonlinearly evolved rotational corrections for motions in fluids, and so the possibilities of broadening the scope of this formalism are discussed.

1988 ◽  
Vol 129 ◽  
pp. 263-264
Author(s):  
X. W. Zheng ◽  
J. M. Moran ◽  
M. J. Reid ◽  
M. H. Schneps ◽  
J. A. Garcia-Barreto ◽  
...  

VLBI OH maser observations simultaneously in right and left circular polarization at the 1665 and 1667 MHz transitions were conducted by taking advantage of the multichannel capability of the Mk III system. The OH maser maps of the right and left circular polarization at both transitions were obtained toward the OH maser sources NGC 6334N, NGC 7538N, NGC 7538S, and G45.07+0.13.


2022 ◽  
Author(s):  
Pengtao Lai ◽  
Zenglin Li ◽  
Wei Wang ◽  
Jia Qu ◽  
Liang Wei Wu ◽  
...  

Abstract Coding metasurfaces have attracted tremendous interests due to unique capabilities of manipulating electromagnetic wave. However, archiving transmissive coding metasurface is still challenging. Here we propose a transmissive anisotropic coding metasurface that enables the independent control of two orthogonal polarizations. The polarization beam splitter and the OAM generator have been studied as typical applications of anisotropic 2-bit coding metasurface. The simulated far field patterns illustrate that the x and y polarized electromagnetic waves are deflected into two different directions, respectively. The anisotropic coding metasurface has been experimentally verified to realize an orbital angular momentum (OAM) beam with l = 2 of right-handed polarized wave, resulting from both contributions from linear-to-circular polarization conversion and the phase profile modulation. This work is beneficial to enrich the polarization manipulation field and develop transmissive coding metasurfaces.


2018 ◽  
Vol 1 (1) ◽  
pp. 28-33
Author(s):  
Farman Ali Mangi

Low loss transmission circular polarizer is proposed for Ku band applications. The designed structure consists of two closely cross metallic strips which are based on FSS for 15.25 GHz and 15.28 GHz applications. The right hand circular polarization (RHCP) and left handed circular polarization (LHCP) are obtained at 15.25 GHz and at 15.28 GHz. The transmission loss through polarizer is important issue for high frequency applications. Due to transmission loss, new techniques are required to reduce the transmission loss of transmitted wave and achieve perfect circular polarization. Meanwhile, low loss transmission has been achieved by using dual layer of strips to obtain perfect circular polarization at certain mentioned resonant frequencies. Theoretically, it is found that the outgoing waves through polarizer are perfect circular polarization at the distinct frequency ranges.


2020 ◽  
Vol 10 (7) ◽  
pp. 2413 ◽  
Author(s):  
Yuntae Park ◽  
Jihoon Bang ◽  
Jaehoon Choi

A beam-steerable dual-circularly polarized 60 GHz antenna array is proposed. A 1 × 4 dual-fed stacked patch antenna array is integrated with an 8 × 8 Butler matrix. By utilizing the 8 × 8 Butler matrix, the proposed antenna array generates dual-circular polarization with beam-steering capability. The proposed antenna array system demonstrates good reflection coefficients in the frequency band ranging from 55.3 GHz to 64.9 GHz and has a mutual coupling of less than −10 dB over the frequency range of 57.5 GHz–63.2 GHz. At 60 GHz, the maximum gains and beam-steering angles for input ports 2, 4, 5, and 7 are 9.39 dBi at −38°, 10.67 dBi at −11°, 10.63 dBi at +11°, and 9.38 dBi at +39°, respectively. It is also demonstrated that the dual-polarization is well formed by switching the excitation ports. The right-handed circular polarization (RHCP) is formed when four ports from port 1 to port 4 are excited and left-handed circular polarization (LHCP) is formed when four ports from port 5 to port 8 are excited. The proposed antenna array system could be a good candidate for millimeter-wave 5G applications that require wide beam coverage and polarization diversity.


2017 ◽  
Vol 9 (8) ◽  
pp. 1695-1703
Author(s):  
Haixiong Li ◽  
Yunlong Gong ◽  
Jiakai Zhang ◽  
Jun Ding ◽  
Chenjiang Guo

In this paper, a coplanar waveguide (CPW)-fed dual-band uniplanar tri-polarization reconfigurable antenna based on the PIN diode switch is proposed. The proposed antenna can be reconfigured between the linear polarization (LP) and the circular polarization (CP) mode, including both the right-handed circular polarization and left-handed circular polarization simultaneously within the dual operating bands. The central frequencies of the bands are 2.63 and 4.42 GHz, respectively, and the overlapped operating bandwidth is 17.8 and 3.40%. The proposed reconfigurable antenna is a closed-slot antenna fed by the CPW transmission line and the reconfigurable mechanism is to regulate the T-shaped driven stub through switching the PIN diodes on and off. The scattering parameters, axial ratio, radiation pattern, gain, and the radiation efficiency of the proposed antenna are all investigated in the following. The optimized antenna has been fabricated to experimental test, the simulated and the measured results agree well with each other. The lower frequency band of the proposed antenna covers the 2.40 GHz WLAN specification and the upper band can be used for the 5 G communication (4.40–4.50 GHz); therefore it is suitable to be applied in the mobile wireless communication.


1978 ◽  
Vol 220 ◽  
pp. L27
Author(s):  
C. R. Menyuk ◽  
I. I. Shapiro ◽  
J. J. Wittels ◽  
H. F. Hinteregger ◽  
C. A. Knight ◽  
...  

2017 ◽  
Vol 31 (17) ◽  
pp. 1750191 ◽  
Author(s):  
Xiang-An Yan ◽  
Bo-Quan Ren ◽  
Li-Qiang Wang ◽  
Yao-Wu Liu ◽  
Hua-Wa Yu

In this paper, we propose a scheme for manipulating the behavior of optical bistability (OB) and optical multistability (OM) in an N-type four-level atomic system. In the scheme, quantum interference is optimized by the left-handed and the right-handed fields of an elliptically polarized field (EPF). The threshold and the hysteresis cycle shape of OB and OM can be controlled by modulating the intensity of the EPF. Especially, the transition from OB to OM or vice versa can also be easily realized by proper tuning the phase difference between the left-handed and right-handed polarized fields under the optimal intensity of the EPF.


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