共查询到20条相似文献,搜索用时 781 毫秒
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设计了一种16×8脊波导缝隙阵列天线,线阵阵面分成两个子阵,馈电采用同轴馈电与耦合缝隙馈电结合的两级馈电方式,辐射缝隙分布为泰勒分布。天线设计采用近场诊断方法和阻抗过载技术进行优化。天线实物加工测试结果表明,天线在X频段驻波带宽(VSWR≤1.5)为7.3%,最低副瓣达到-25.8 dB,副瓣电平带宽(SLL≤-19 dB)为6.2%。与已有文献相比,该天线同时具备阻抗宽带特性和低副瓣宽带特性,工作频带内具有增益均大于16 dBi的高增益特性。 相似文献
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设计了一种卫星导航终端的小型化四臂缝隙螺旋天线。天线为方形柱状结构,四条缝隙螺旋臂印制在介质基板外表面,馈电网络印制于介质基板内表面进行耦合馈电;馈电网络为弯折的微带线结构,并延伸至天线底部实现同轴馈电。天线尺寸为23.6 mm×23.6 mm×53.0 mm,实测结果表明,|S11 |≤-10 dB 的阻抗带宽为7.63%(1.512~1.632 GHz),轴比≤3 dB 的圆极化带宽为3.35% (1.556~1.609 GHz),在北斗B1频段中心频率(1.561 GHz)和GPS L1 频段中心频率(1.575 GHz)处增益分别达到4.31 dBi 和4.84 dBi。该天线采用缝隙螺旋结构,并通过简易的馈电网络耦合馈电实现螺旋天线的圆极化,结构小巧简单,适合批量生产,可应用于卫星导航系统终端设备。 相似文献
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研究了一种宽阻抗带宽和宽圆极化轴比带宽的缝隙螺旋天线。天线印制在由FR4 介质基板构建的
方形柱状结构的内外表面,两组长短不同的缝隙螺旋臂印制在介质基板外表面并延伸至天线顶部;一条弯折的微带
线作为馈电网络印制在介质基板内表面,通过对各缝隙耦合馈电,实现天线宽阻抗带宽和轴比带宽。实测结果表
明:天线尺寸为0. 111λ0 ×0. 111λ0 ×0. 221λ0(λ0 为北斗B2 中心频率1. 207 GHz 对应的自由空间波长),S11 ≤ -10 dB
的阻抗带宽为1. 158~1. 778 GHz,轴比≤3 dB 的圆极化带宽为1. 133~1. 918 GHz。该天线采用缝隙螺旋结构,通过
简易的馈电网络实现天线小型化和宽频带特性,在卫星导航系统中具有较好的应用前景。 相似文献
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提出了利用微带天线的宽带输入阻抗模型进行有源集成天线的设计方法以预测有源集成天线(AIA)的辐射特性和谐波特性.谐波平衡法被用于得到AIA的谐波特性和阻抗模型的端口电压.然后端口电压作为激励源计算天线特性.实验结果显示该方法可以简单有效进行有源集成天线设计. 相似文献
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The design of small slot arrays 总被引:13,自引:0,他引:13
The differences in mutual coupling for a central slot and a peripheral slot cannot be ignored in small arrays if good patterns and impedance are to be obtained. A theory has been developed whereby the length and offset of every slot in the array can be determined, in the presence of mutual coupling, for a specified aperture distribution and impedance match. The theory enlarges on Stevenson's method, and uses a modified form of Booker's relation based on Babinet's principle to treat nonresonant longitudinal shunt slots in the broad wall of a rectangular waveguide. A general relation between slot voltage and mode voltage is developed, and then formulas are derived for the active, self-, and mutual admittances among slots. These formulas result in a design procedure. Analogous treatments of inclined series slots in rectangular guide and of strip-line-fed slots are possible. Comparison between various experiments and the theory is presented. Tests of the theory include the resonant length of a zero offset slot, resonant conductance versus offset and resonant conductance versus frequency for a single slot, and self- and mutual admittances for two staggered slots. The design and performance of a two-by-four longitudinal shunt slot array is also described. 相似文献
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Cheng-Geng Jan Powen Hsu Ruey-Beei Wu 《Antennas and Propagation, IEEE Transactions on》1993,41(4):488-492
An analysis for calculating the mutual impedance between two edge slots in a linear slotted waveguide array is presented. The analysis uses a 90° wedge Green's function to account for the influence of the waveguide corners on the evaluation of the external mutual coupling. A novel asymptotic formula for the 90° wedge Green function's is derived to expedite the numerical analysis for slots with large separation. Numerical results show that the phase of mutual impedance retards linearly with slot separation and the magnitude decays as the separation is increased. However, the mutual impedance of edge slots is larger and decays more slowly than that of longitudinal slots or other slots in a large ground plane. The distinguished characteristics can be attributed to the energy guiding effect of the waveguide corners, which is discovered and verified mathematically and numerically. Also shown in the numerical calculations are the incremental conductances of the individual slots in a linear edge slot array, which are compared, and found to be in good agreement, with the available experimental data 相似文献
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一种新型矩形波导裂缝天线的分析与设计 总被引:8,自引:0,他引:8
针对任意两个横缝位于馈电矩形波导终端的短路圆盘上的情况.本文运用伽略金方法分析了一种新型双裂缝天线的反射与辐射特性:分析中考虑了缝隙间的内部互耦与外部互耦:根据分析结果,首次设计并研制了这种工作于C波段的新型天线,实验结果和设计指标吻合较好.它适合高速飞行器载体的特殊应用. 相似文献
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Study of a CPW inductively coupled slot antenna 总被引:3,自引:0,他引:3
Coplanar waveguide (CPW) fed slot antennas are attractive due to fabrication simplicity and ease of integration with active devices. A new concept for exciting slots with a CPW line based on inductive coupling is presented. It is described how this coupling structure can be designed to tune the impedance of the antenna over a wide range. Single elements and arrays designed for 5- and 25-GHz operation are described. Simulated and measured characteristics are presented. This new coupling topology is particularly suitable for series-fed array configurations and broad-band design 相似文献
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Analysis of a centered-inclined waveguide slot coupler 总被引:5,自引:0,他引:5
Integral equations are developed for a centered-inclined coupling slot (including the effect of finite wall-thickness of the common broad-wall) and the slot-aperture electric intensity field is found using the method of moments. Numerical results for resonant length, backscattered wave amplitude, and phase variation off-resonance are presented over a range of values of the waveguide b dimension, wall thickness, slot width, and frequency. It is shown that the resonant length is relatively insensitive to slot tilt, &thetas;, for a standard-height X -band waveguide, whereas its dependence on &thetas; is significant for reduced-height waveguides. The phase variation of scattered TE10 waves in both waveguides off-resonance is less for wider slots and smaller b dimensions. Shunt-series coupling slots exhibit greater phase variation off resonance when compared to a centred-inclined coupling slot. Also, the former has a longer resonant length for a smaller b dimension and for a wider slot. Thus the centred-inclined slot coupler possesses superior characteristics. The higher-order mode coupling between a centred-inclined slot coupler and a pair of straddling radiating slots in the branch waveguide is significant 相似文献
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Sasazawa H. Oshima Y. Sakurai K. Ando M. Goto N. 《Antennas and Propagation, IEEE Transactions on》1988,36(9):1221-1226
Coupling between slots and slow-wave waveguides in a radial line slot antenna (RLSA) is discussed. Field analysis of the waveguide with a surface impedance wall revealed a considerable change in the propagation constant due to coupling. Experiments were performed to confirm these results and to obtain the surface impedance for actual slots. The change in the propagation constant caused the antenna efficiency to exhibit its maxima at two separated frequencies. An efficiency of 60% and 50% was measured at 11.6 and 12.4 GHz, respectively, which confirms a theoretical prediction. This effect suggests the possibility of broadband planar antennas 相似文献
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A numerical formulation involving the Fourier transform and the combined-field integral equation is presented to calculate the mutual admittance between axial slots or circumferential slots in arbitrarily shaped cylinders. Two cases are considered: coupling between two circumferential slots and coupling between two axial slots. The slots are assumed to be waveguide-fed apertures excited with the TE10 waveguide mode, with no higher-order modes included in the model. The combined field-integral equation (CFIE) formulation was used in conjunction with the magnetic field integral equation (MFIE) to solve the resulting two-dimensional integral equation. Formulations for the axial slot case are discussed. Results concerning the discretization and truncation of the spectrum, as well as the accuracy of the procedure, are presented for both axial and circumferential cases. The accuracy of the procedure is demonstrated by comparison with eigenfunction data for circular cylinders 相似文献
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Wu Ren Ben-Qing Gao Zheng-Hui Xue Wei-Ming Li Bo Liu 《Antennas and Propagation, IEEE Transactions on》2004,52(9):2436-2444
A rigorous analysis of the resonant characteristics for a broad wall waveguide slot by using the finite-difference time-domain method is presented. Four types of slots including a radiating longitudinal shunt slot, a longitudinal/transverse coupling slot, a centered-inclined coupling slot and a compound coupling slot are analyzed. Lots of slot characteristics such as the resonant length, scattering parameters and normalized admittance in different offsets, tilt angles or slot sizes are obtained. Because the shape of slots is a rectangle with rounded ends in practical fabrication, an accurate modeling and computation for the slots with rounded ends is implemented, and the resonant lengths calculated coincide well with the Stegen's measured data and method of moments results. From these computed results, it is found that all the resonant characteristics of the slots with rounded ends are significantly different from those with normal rectangular ends. 相似文献