Wideband planar array antenna in C band for synthetic aperture radar applications

Abstract

nonlinear gain successfully prevents the energy exchange between two solitons traveling along two orthogonal polarization channels, respectively; in other words, the propagation of two dark solitons along two orthogonal polarization channels is mutually independent. This property is beneficial to the soliton polarization division multiplexing.In the fiber with randomly varying birefringence, the effects of interaction between the two dark solitons have been investigated with the use of numerical simulations. The results obtained show that the interaction between two dark solitons in the same polarization channel is weak, and the dark soliton propagation instability mainly comes from the randomly varying birefringence. On the contrary, the interaction between two dark solitons in two orthogonal polarization channels is strong, which leads to soliton splitting and soliton propagation instability. The randomly varying birefringence also has effects on dark soliton propagation; thus dark soliton propagation instability comes from both of these effects. The nonlinear gain can be introduced to effectively suppress the interaction and stabilize the dark soliton propagation either in the same polarization channel or the two orthogonal polarization channels. The use of a nonlinear gain is simple and efficient and has potential applications in the design of a polarization-division multiplexed system. ABSTRACT: The design and development of a wideband dual polarized planar array antenna of 3 ϫ 6 elements in C band is presented.The center frequency is 5.3 GHz. The single radiating element used in the array configuration is of stacked SSFIP. The antenna has been developed for beam pointing of 10°and side-lobe level better than Ϫ15 dB by proper choice of the complex excitation coefficients. The array antenna offers a bandwidth of 20% for a VSWR ratio of 2:1. The measured S parameters and radiation patterns are presented. ABSTRACT:Analytical expressions for parasitic-element-dependent scattering parameters of a non-self-aligned GaN MESFET are evaluated and their variation with frequency is shown. Maximum stable gain and maximum transducer power gain of the device are also evaluated and it is found that a GaN MESFET with the dimensions (1.5 ϫ 100 m) has maximum stable gain of about 13 dB.

Wideband planar array antenna based on SCRLH-TL for airborne synthetic aperture radar application

“…The number of elements required in the elevation and azimuth plane was six. Pattern synthesis based on Woodward techniques [26] was used to determine the complex excitation coefficients for the individual array elements to achieve the required pattern shape. The illumination pattern was achieved by applying a specific amplitude and phase to the patches in the array according to the excitation coefficient outlined in Table III.…”

Wideband dual-polarized slot-coupled microstrip array for synthetic aperture radar application

“…Ref. [3] proposes a 6 × 3 array antenna where the element is fed by the orthogonal and stacked microstrip lines through two crossed rectangular slots cut in the ground plane and located underneath the center of patches, resulting in the isolation better than 26 dB with the cross-polarization level of −19-−22 dB. Recently, a wideband aperture-coupled 2 × 4 microstrip array antenna using inverted feeding structures is presented for both the personal communications services (PCS) and the international mobile techcommunications-2000 (IMT-2000) services simultaneously.…”

“…Several dual-polarized aperture-coupled microstrip antennas with different feeding structures have been reported in Refs. [1][2][3][4][5][6]. In Ref.…”

Experimental characterization of a broadband dual‐polarized microstrip antenna for X‐band SAR applications

“…Literature [2] developed a probe-fed stacked microstrip patch antenna for the dual-polarized C-band SAR application. Aperture-coupled microstrip patch arrays are used in several SAR antenna designs [3][4][5][6].…”