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1.
A pair of novel 180deg broadband microstrip baluns are used to feed a dual-polarized patch antenna. The 180deg broadband balun delivers equal amplitude power division and consistent 180deg (plusmn5deg) phase shifting over a wide bandwidth (>50%). We demonstrate that for a dual-polarized quadruple L-probe square patch antenna, the use of the proposed 180deg broadband balun pair, in place of a conventional 180deg narrowband balun pair, provides improved input port isolation and reduced H-plane cross-polarization levels over a wider frequency range, while maintaining low E-plane cross-polarization levels and stable E- and H-plane co-polarization patterns throughout the impedance passband 相似文献
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Zhen-Yu Zhang Ke Wu 《Microwave and Wireless Components Letters, IEEE》2007,17(12):843-845
A broadband planar balun is presented in this work that makes use of a substrate integrated waveguide (SIW) technique using a printed circuit board process. The proposed balun structure is able to operate at millimeter wave frequencies and it does not require any tight line coupling sections as frequently used in monolithic microwave integrated circuit balun design. In addition, this balun can be integrated with other planar topologies including nonplanar circuits made of the same substrate for achieving high efficiency. This balun structure consists of a 3 dB SIW power divider and microstrip lines that are placed on both sides of the substrate at balanced ports to obtain an 180deg phase shift. The concept is validated by simulations and measurements. Our measured results suggest that a 10 dB return loss at unbalanced port can easily be achieved across a 42% bandwidth from 19 to 29 GHz. Measured amplitude and phase imbalance between two balanced ports are within 1 dB and plusmn5deg, respectively. 相似文献
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提出并设计了一种低成本宽带90°巴伦电路结构,电路由宽带耦合威尔金森功分器、弱耦合线和扇形阶跃阻抗谐振器级联的宽带90°移相器组成。利用电磁仿真软件HFSS对工作在中心频率为1.65GHz 的微带电路进行建模和仿真。采用PCB工艺制作了电路实物并利用矢量网络分析仪进行测试;对比得出仿真与测试结果十分吻合,该巴伦实测相对带宽大于117.0% (0.65~2.58GHz),带内各端口回波损耗好于12.6 dB,输出端口隔离度大于13.1dB,带内插入损耗小于0.5 dB,相位误差小于90°±7.6°。与现有的结构和设计相比,该巴伦不仅具有更大的工作频带和单层电路布局,而且具有容易加工、成本低的优点。 相似文献
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Hwann-Kaeo Chiou Tsung-Yu Yang 《Microwave Theory and Techniques》2008,56(4):835-848
This study presents an asymmetric broadside coupled balun with low-loss broadband characteristics for mixer designs. The correlation between balun impedance and a 3D multilayer CMOS structure are discussed and analyzed. Two asymmetric multilayer meander coupled lines are adopted to implement the baluns. Three balanced mixers that comprise three miniature asymmetric broadside coupled Marchand baluns are implemented to demonstrate the applicability to MOS technology. Both a single and dual balun occupy an area of only 0.06 mm2. The balun achieves a measured bandwidth of over 120%, an insertion loss of better than 4.1 dB (3 dB for an ideal balun) at the center frequency, an amplitude imbalance of less than 1 dB, and a phase imbalance of less than 5deg from 10 to 60 GHz. The first demonstrated circuit is a Ku-band mixer, which is implemented with a miniaturized balun to reduce the chip area by 80%. This 17-GHz mixer yields a conversion loss of better than 6.8 dB with a chip size of 0.24 mm2. The second circuit is a 15-60-GHz broadband single-balanced mixer, which achieves a conversion loss of better than 15 dB and occupies a chip area of 0.24 mm2. A three-conductor miniaturized dual balun is then developed for use in the third mixer. This star mixer incorporates two miniature dual baluns to achieve a conversion loss of better than 15 dB from 27 to 54 GHz, and occupies a chip area of 0.34 mm2. 相似文献
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A novel metamaterial broadband microstrip balun design is proposed. The broadband balun consists of a pair of identical metamaterial transmission lines. In the odd mode, a virtual ground is formed between the symmetric plane. The odd mode is allowed while the even mode is rejected. No vias are required to realize the shunt inductors of the metamaterial lines, and no power divider is used. Baluns with good performance can be achieved. In this letter, two baluns are fabricated and measured. For the balun with seven units, the output amplitude difference is less than 0.7 dB, and the differential phase is 181deg plusmn 3deg from 1.6 to 3.6 GHz, while the input return loss is greater than 10 dB. 相似文献
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《Electronics letters》2008,44(21):1259-1261
A new uniplanar monolithic microwave integrated circuit (MMIC) balun using lumped circuits is presented. The proposed planar balun consists of a wideband Wilkinson power divider and a broadband 180° phase shifter using novel series and parallel LC reflective terminating circuits. To demonstrate the design methodology, a 24?44 GHz MMIC balun was realised as a 1.4 mm 2> GaAs chip. The measured return losses for the unbalanced and balanced ports are better than 212, 210 and 27 dB, respectively. The measured amplitude and phase imbalance between the two output ports are less than 0.5 dB and 7°, respectively, and maximum insertion loss is 5 dB. 相似文献
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针对高功率天线的差分馈电和阻抗匹配问题,文中提出了一种基于同轴线结构加载铁氧体磁环的宽
带巴伦模型。双同轴线具有阻抗变换功能和较好的功率承载能力,铁氧体磁环改善了巴伦在低频时的输入匹配和
两个输出端口不平衡度。仿真和实测表明,此巴伦在0. 05~1. 24 GHz 内回波损耗低于-10 dB,去除3. 0 dB 系统插损
后单端插入损耗在1. 5 dB 以内,两端输出的相位不平衡度在5°以内,幅度不平衡度在2%以内。通过分析巴伦的电
磁热损耗场、温度场和应力形变场,验证了巴伦在高功率馈电下的工作性能,结果表明此巴伦在工作频带内能够承
受500 W 的功率。 相似文献
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A novel printed crossed dipole with broad circular polarisation (CP) is proposed. This dipole is also utilised in 1 times 2 and 2 times 2 array antennas. The proposed dipole can produce CP because of its sequentially rotated configuration. The broadband CP performance is achieved because of a parasitic dipole crossing over the original dipole with a 90deg phase delay line. The experimental results show that single, 1 times 2, and 2 times 2 antennas yield bandwidths of 15.6, 24.5, and 39.2% for 3 dB axial ratio, respectively. 相似文献
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RongLin Li Laskar J. Tentzeris M.M. 《Microwave and Wireless Components Letters, IEEE》2006,16(1):52-54
A broadband circularly polarized rectangular loop antenna is developed. The broadband performance is achieved by adding a pair of parasitic loops inside the rectangular loop. Good impedance matching is obtained by introducing a broadband balun. The proposed rectangular loop has a bandwidth of 46% for axial ratio/spl les/2dB and 50% for VSWR/spl les/2 with a gain of around 8dBi. 相似文献
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Wideband LC balun transformer using coupled LC resonators embedded into organic substrate 总被引:1,自引:0,他引:1
Jong Cheol Park 《Microelectronics Journal》2009,40(11):1555-1560
In this paper, wideband LC balun using coupled LC resonator has been newly designed, simulated, and fabricated. The proposed balun has a novel scheme which consists of two pairs of coupled embedded LC resonators which share one resonator with each other. The coupled resonators are applied to provide a precise phase difference of 180° and an identical magnitude between two balanced ports and DC isolation characteristic with impedance transformation. Furthermore, proposed resonators have relatively small inductance values which can be easily embedded into the organic package substrate. In order to reduce the size of embedded capacitors, BTO composite high dielectric film was applied to increase their capacitance densities. The measured results of fabricated wideband balun exhibited an insertion loss of 1.8 dB, a return loss of 10 dB, a phase imbalance of 0.5°, and magnitude imbalance of 0.7 dB at frequency bandwidth of 700 MHz ranged from 1.8 to 2.5 GHz, respectively. They agreed well with the simulated ones. The fabricated balun has a relatively small volume of 2 mm×3.5 mm×0.66 mm (height). 相似文献
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A new conveyor-based single-ended to differential balun is proposed. Thanks to the quasi-absence of passive components, this is an extremely size-efficient balun (0.036 ). The use of a new impedance-matching technique makes this balun the first transistor-based solution with controllable port impedances. Fabricated in a 0.35-mum SiGe BiCMOS technology with fT=45 GHz, the balun shows the following performance: wideband impedance matching at all three ports, good balance between the two outputs (better than 3 dB in amplitude and 13deg in phase) over frequency bands extending from 0 to 3 GHz, linear operation for powers up to input powers of -2 dBm, and stability against temperature and process variations. 相似文献
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Zhen-Yu Zhang Yong-Xin Guo Ling Chuen Ong Chia M.Y.W. 《Microwave and Wireless Components Letters, IEEE》2005,15(6):416-418
A new wide-band microstrip balun implemented on a single-layer printed circuit board (PCB) is presented in this letter. The proposed planar balun consists of a wide-band Wilkinson power divider and a noncoupled-line broad-band 180/spl deg/ phase shifter. To demonstrate the design methodology, one prototype is realized. The new design was simulated and validated by the measurement. Measured results show that 10-dB return loss of the unbalanced port has been achieved across the bandwidth from 1.7 GHz to 3.3 GHz, or 64%. Within the operation band, the measured return losses for both the two balanced ports are better than -10 dB, and the balanced ports isolation is below -1.5 dB. The measured amplitude and phase imbalance between the two balanced ports are within 0.3 dB and /spl plusmn/5/spl deg/, respectively, over the operating frequency band. 相似文献
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A novel circular ring slot antenna which has a stripline hybrid coupler feed network is proposed for generating broadband circular polarisation performance. A broad impedance bandwidth (VSWR 2:1) at 20.5%, and a CP bandwidth at 9% for a <3 dB axial ratio have been achieved 相似文献
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A circularly-polarised antenna which has a novel feeding structure like a substrate integrated waveguide, a cavity-backed resonator and a conventional ring-slot antenna is proposed for right-handed circular polarisation (RHCP) in a single-layered fabrication. The CP generation and broadband impedance matching characteristics are accomplished by using a simple shorting via between the top patch and bottom ground plane and inserting inductive via arrays at the input port, respectively. A broadband impedance bandwidth of 18.74% and a RHCP axial ratio of 2.3% have been obtained under the condition of less than VSWR 2:1 and axial ratio -3 dB, respectively. 相似文献
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提出了一种具有陷波特性的宽带微带线-槽线巴伦。通过采用阶梯型阻抗变换器,拓宽了巴伦的工作带宽。同时,在微带线的开路枝节上增加了一个1/4波长的开路枝节,使得巴伦可以在所需的频段内实现陷波特性。仿真结果表明,巴伦除在1.25~1.46 GHz频带内实现陷波外,在0.38~2 GHz频带内反射系数均<-10 dB,插入损耗均优于-1.8dB。 相似文献
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A four rhombic loop antenna for circular polarisation is proposed. This antenna has a high gain of about 9.7 dBi and a broad beam of more than 130° half power beam width. Four parasitic loops are added inside the original four loops to increase the axis ratio bandwidth. A broadband balun is incorporated into the antenna for impedance matching. Details of the antenna design and experimental results are presented. 相似文献