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A low VSWR and high efficiency antenna array operating in the Ku band for satellite communications is presented in this paper. To achieve high radiation efficiency and broad enough bandwidth, all-metal radiation elements and full-corporate waveguide feeding network are employed. As the general milling method is used in the multilayer antenna array fabrication, the E-plane waveguide feeding network is adopted here to suppress the wave leakage caused by the imperfect connectivity between adjacent layers. A 4 × 8 elements array prototype was fabricated and tested for verification. The measured results of proposed antenna array show bandwidth of 6.9% (13.9–14.8 GHz) for VSWR < 1.5. Furthermore, antenna gain and efficiency of higher than 22.2 dBi and 80% are also exhibited, respectively.

A wideband full-metal planar antenna array with full-corporate feed-network is proposed. Cavity and slot are used as the basic radiation element and T-shaped walls are employed in the cavity to achieve wide bandwidth. $E$ -plane waveguide feed-network configuration is utilized so as to suppress wave leakage between adjacent layers when the antenna is fabricated by a conventional machining technique. An $8 \times 8$ antenna array prototype with optimized parameters is tested. Experimental results show that the bandwidth of ${\text{VSWR}} is up to 36.9% ( $10.24-14.87\;{\text{GHz}}$ ). More than 60% aperture efficiency and higher than 23.4 dBi gain are achieved over the operational bandwidth.

Design of a dual-wideband dual-polarized planar shared aperture microstrip antenna array is proposed in this article. Differential feeding method is used to enhance the isolation between polarizations of the antenna in both bands.Corporate feed network is used for good radiation pattern results. Further, the coupling between the feed networks the two orthogonal polarizations is minimized. This is achieved using the antenna elements to separate the feed networks for orthogonal polarizations. To verify the antenna design, a prototype is fabricated and measured. For VSWR, the antenna can cover from 1.07 to 1.24 GHz (14.7%) and from 8.3 to10.3 GHz (21.5%), respectively. The measured isolation between bands is higher than 30 dB and the isolation between polarizations is higher than 22.5 and 29.6 dB in L- and X-band, respectively. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2197–2204, 2015

A broadband and high-gain slot antenna array operating in the Ku-band is reported in this study. The antenna is with waveguide-fed cavity backed configuration and made entirely via simple milling process. The overall antenna structure consists of four layers. The bottom layer is a waveguide feed network to provide corporate power division. In turn, the waveguide feed network is excited by a conventional coaxial probe from the back. The waveguide network couples energy to an array of cavity via an aperture plate. These constitute the middle two layers. Each cavity then excites a subarray of 2 × 2 radiating slots in the top layer. The radiating slot elements and the feed network are designed to achieve wide bandwidth and high-gain performance. Finally, an 8 × 8 array antenna has been designed and fabricated with about 25 dBi gain over 14.8% bandwidth, and the cross-polarisation was around -30 dB in the boresight.

A low profile wideband 16×16 waveguide array with dual circular polarizations is proposed. A 90 degrees hybrid is integrated with the array to obtain the dual circular polarizations. The whole metal structure is adopted to achieve high radiation efficiency. This antenna will be fabricated with Metal 3D Printing.

A millimeter-wave integrated diplexer is introduced utilizing metal insert channel filter technology and E-plane waveguide matching configurations. Special waveguide transformer sections are optimized by using HFSS. Computer-optimized design data are presented in the Ka-band frequency range.

A shared-aperture dual-wideband dual-polarized planar microstrip array is investigated.The operating frequencies are at L- and X-bands. For both bands, stacked patches are selected as the radiating elements to meet the bandwidth requirements. A low-profile design of a planar microstrip array with 2 × 1 L-band elements interleaved with 16 × 8 X-band elements has been achieved. The design is discussed in detail, and the measured results are presented. The measured bandwidth of VSWR < 2 reaches 8.1 and 13% for L- and X-bands, respectively. The measured isolation between the L- and X-band is below −35 dB, and the isolation between the cross-pol ports is below −26 and −24 dB for L- and X-band, respectively. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:486–491, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26579

The Direct Metal Laser Sintering (DMLS) 3-D printing technique is used to fabricate a relatively large 8×8 wideband waveguide array with an integrated corporate-fed network. This DMLS rapid prototyping technique offers the flexibility to fabricate complicated waveguide-based structures with good reliability and high-precision. Experimental results show antenna efficiency is higher than 80% over a wide operation bandwidth and even exceeding 90% at most frequencies. This work demonstrates the 3-D DMLS technique is a promising manufacturing method for the fabrication of complex waveguide antenna arrays.

The aim of this paper was to investigate a hybrid technology that combined striplines and E-plane metallic waveguides for the application of dual-polarized array in Ku-Band. The array was a sandwich structure consisting of multiple metal and substrate layers. The stripline circuits coupled the input power from the E-plane waveguide to form a hybrid structure, which was used to feed the radiators directly to obtain high gain. Here, the design of an efficient waveguide-to-stripline structure was a key issue to the whole feeding network as it was used as main feed line to construct a 4×4 Ku-Band dual-polarization array with circular radiators. Design details of the array and structural realization are given. Result data shows a good agreement between simulation and measurement, which reveals the hybrid structure is a promising technique for wideband and high-gain dual-polarized array application.

A mirror-symmetric hybrid feeding network is proposed in this paper for the design of a dual-polarization high-gain array antenna in Ku-band. The hybrid structure consists of E-plane waveguides and series-feed stripline circuits. Input power is coupled from a simple E-plane waveguide to all stripline branches, which are used to excite the circular waveguide radiators individually. However, for the sake of avoiding long line effect from the series-feed circuits in large array, key issue of equal-phase distribution among radiators should be solved efficiently. Two 8×4 stripline sub-networks are placed in a mirror-symmetric position. Such arrangement could introduce another 180 degree phase difference to compensate the antiphase caused by E-plane T-junction waveguide power divider in the design. In turn, all the radiators could be fed in equal-phase. The hybrid feeding network has been realized on an 8×8 array. Design details of the feeding network and array structure are given. The mirror-symmetric hybrid structure can be considered as a good candidate for dual-polarized large array application.

This paper describes the design of a dual-wideband dual linear polarization shared aperture patch antenna. The antenna consists of one antenna element for L-band and an 8×8 planar array for X-band, sharing the same radiation aperture. The array, together with the feeding network is analyzed with HFSS software. The Return Loss, Isolation, and Radiation Patterns of the array are presented. The impedance bandwidth of this antenna array, corresponding to 10dB Return Loss is 13.0% and 14.7% in L- and X-band respectively. The isolation between the orthogonal polarization ports is better than 25 dB and 35 dB in L- and X-band respectively. The cross-polarization is below −22 dB and −25 dB in L- and X-band respectively.

Based on physical meaning of Melnikov function, we establish a method to calculate period doubling bifurcation and discuss this kind of bifurcation of soft spring Duffing system and find that the result is analogous to subharmonic bifurcation, that is, period doubling bifurcation will appear if damping is small and amplitude of excitation is big. Thi coincides with facts of physics.