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A Miniaturized Printed Dipole Antenna with V-Shaped Ground for 2.45 GHz RFID Readers
Zhiguang Fan;Shan Qiao;Jiang Tao Huang-Fu;Li-Xin Ran
PIER , 2007, DOI: 10.2528/PIER07022501
Abstract: In this paper, a miniaturized printed dipole antenna with the V-shaped ground is proposed for radio frequency identification (RFID) readers operating at the frequency of 2.45 GHz. The principles of the microstrip balun and the printed dipole are analyzed and design considerations are formulated. Through extending and shaping the ground to reduce the coupling between the balun and the dipole, the antenna's impedance bandwidth is broadened and the antenna's radiation pattern is improved. The 3D finite difference time domain (FDTD) Electromagnetic simulations are carried out to evaluate the antenna's performance. The effects of the extending angle and the position of the ground are investigated to obtain the optimized parameters. The antenna was fabricated and measured in a microwave anechoic chamber. The results show that the proposed antenna achieves a broader impedance bandwidth, a higher forward radiation gain and a stronger suppression to backward radiation compared with the one without such a ground.
Compact Microstrip Fed Dual Band Printed Rectangular Patch Antenna For Wlan/Wimax  [PDF]
P.PRABHU,M.RAMKUMAR,S.PRADHAP,S.NAVIN
International Journal of Innovative Research in Science, Engineering and Technology , 2013,
Abstract: Compact microstrip fed dual band printed rectangular patch antenna for WLAN/WiMAX applications presented ,The proposed dual band antenna consist of rectangular patch and dipole arms ,tuning the geometry of the proposed antenna operate at two different frequencies ,such as 2.4GHz with -24 dB return loss and 3.2 GHz with -14 dBi return loss .The antenna consist of a printed rectangular patch with microstrip feeding structure. In this proposed antenna achieves the radiation pattern omnidirectional ,fairly omnidirectional and broad bandwidth ,the simulated results of the proposed antenna prototype provided .
Study on a Miniature UWB Wafer-Dipole Printed Antenna FED by Balanced Micro-Strip Line
Shu Lin;Run-Nan Cai;Guan-Long Huang;Xin-Yue Zhang;Xing-Qi Zhang;Li-Zhuo Wang;Jin-Xiang Wang
PIER C , 2011, DOI: 10.2528/PIERC10102905
Abstract: A novel wafer-dipole printed antenna fed by balanced micro-strip line is proposed, and the adoption of the balanced micro-strip line can effectively solve the feeding problem of the UWB dipole antenna. The wafer-dipole and a branch of the balanced microstripline are printed on one side of FR-4 substrate (1mm thickness), and the later is connected to a wafer directly, while the other branch is printed on the back side of the substrate and connected the other wafer with a via-hole. The measured results show that the antenna impedance bandwidth is from 3.0 GHz to 15.0 GHz with VSWR < 2, and the ratio bandwidth is about 5:1. Moreover, the antenna size is just 40 mm×20 mm with simple structure, which is well suited for short-distance UWB communications.
Super-Wideband Printed Asymmetrical Dipole Antenna
Xiu-Hua Jin;Xiao-Dong Huang;Chong-Hu Cheng;Lei Zhu
PIER Letters , 2011, DOI: 10.2528/PIERL11090506
Abstract: The proposed dipole antenna consists of two printed strips with unequal lengths and is fed by a coplanar strip (CPS) line. As the antenna parameters and port impedance are properly selected, a super wide operating band (|S|<-10 dB) of 3.5 to 20.0 GHz is realized. Antenna samples were fabricated using standard PCB process. The area of the constructed dipole antenna is 40.0x5.0 mm. The S-parameter measurement was performed via a transition (CPS to double-sided parallel strip line) and transformer (190 to 50 Ohm). The measured fractional bandwidth achieved 139.3% (from 3.4 to 19.0 GHz) as predicted, over which the antenna peak gain is better than 0 dBi.
Dual-Band Printed Dipole Antenna with Parasitic Element for Compensation of Frequency Space Attenuation
International Journal of Electromagnetics and Applications , 2012, DOI: 10.5923/j.ijea.20120205.05
Abstract: A Dual-band printed dipole antenna is proposed for 2.45 GHz Bluetooth (ISM) and wireless area network (WLAN) 5.8 GHz applications. The objective of the special design is to compensate the space attenuation difference between the frequency of 2.45 GHz and the frequency of 5.8 GHz. Like the space attenuation difference is about 3.5 dB, the studied antenna must to have 3 dB more gain at 5.8 GHz than at 2.45 GHz. The prototype is fabricated and measured, and the results are in good agreement with the simulated ones. The presented antenna achieves directional radiation in the two operating bands, and gets the performances that reflection coefficient better than -10 dB with sufficient bandwidth and gain 5-8 dB, making it suitable for the base station in wireless communications.
A Printed Log-Periodic Tree-Dipole Antenna (Plptda)
Shu Lin;Shan Luan;Yudie Wang;Xiao Luo;Xue Han;Xing-Qi Zhang;Yu Tian;Xin-Yue Zhang
PIER M , 2011, DOI: 10.2528/PIERM11080109
Abstract: A miniaturized printed log-periodic fractal dipole antenna is proposed. Tree fractal structure is introduced in an antenna design and evolves the traditional Euclidean log-periodic dipole array into the log-periodic second-iteration tree-dipole array (LPTDA) for the first time. Main parameters and characteristics of the proposed antenna are discussed. A fabricated proof-of-concept prototype of the proposed antenna is etched on a FR4 substrate with a relative permittivity of 4.4 and volume of 490 mm × 245 mm × 1.5 mm. The impedance bandwidth (measured VSWR < 2) of the fabricated antenna with approximate 40% reduction of traditional log-periodic dipole antenna is from 0.37 to 3.55 GHz with a ratio of about 9.59 : 1. Both numerical and experimental results show that the proposed antenna has stable directional radiation patterns and apparently miniaturized effect, which are suitable for various ultra-wideband applications.
Design, Analysis, and Measurements of an Antenna Structure for 2.4?GHz Wireless Applications  [PDF]
Constantinos I. Votis,Panos Kostarakis,Antonis A. Alexandridis
International Journal of Antennas and Propagation , 2010, DOI: 10.1155/2010/796154
Abstract: This paper reports measured results of a multielement antenna implementation, we constructed, that performs at 2.4?GHz ISM band. Particular emphasis was given to the scattering parameters and validation characterization of this antenna structure. The constructed multielement antenna that was studied in both azimuth and elevation planes consists of a number of printed dipoles with integrated baluns. Due to its multielement construction, the proposed antenna structure is suitable for applications that require multielements nature such as MIMO, channel sounder, and digital beamforming. 1. Introduction Requirements for wider bandwidth capabilities, higher bit rates, and better quality of services are crucial for wireless communication applications. Scientific and engineering community provides a number of novel techniques and methods to meet these requirements. These offer efficient improvements on the throughput of the wireless systems and are usually applied on compatible radiation structures, provided by single or multiple-element antenna architectures. These were further studied in terms of radiation efficiency and performance. Besides, the printed dipole antenna with integrated balun is an attractive type of radiation element that was studied and investigated in previous literature [1–4]. This architecture offers small size, easy, and low-cost antenna implementation. It has omnidirectional radiation characteristics, providing narrowband wireless applications. Several techniques have been introduced to improve the efficiency of this radiation element in terms of frequency bandwidth and antenna gain [5, 6]. Furthermore, this antenna is usually combined with various types of reflector structures in order to improve its directivity and performance efficiency. Microwave theory indicates the impact of the reflector presence and introduces essential observations and principles that confirm the corresponding effects [7, 8]. In each case, scattering parameters and radiation patterns are meaningful on antenna design. The corresponding simulated and experimental results provide an interesting amount of measurements that enhance antenna efficiency and performance. In addition, the printed dipole antenna with integrated balun and a reflector structure could support multielement antenna configurations because of the compactness and geometry of the whole implementation. The corresponding literature indicates that these multiple-element antenna configurations are mainly used in modern wireless communication applications such as MIMO (Multiple-Input Multiple-Output).
Dual-Band and Wideband Design of a Printed Dipole Antenna Integrated with Dual-Band Balun
Xi Li;Yang Lin;Shu-Xi Gong;Yan-Jiong Yang
PIER Letters , 2009, DOI: 10.2528/PIERL08120504
Abstract: A dual-band printed dipole antenna with integrated balun feed is given in this paper. First, the fork-shaped slot is etched on the arms of the printed dipole antenna to achieve the dual-band operation with resonances at WLAN bands. The radiating element without balun is optimized and operates at 2.4 GHz (2180-2750 MHz) and 5.2 GHz (5040 MHz-5480 MHz) where return loss is less than -10 dB. In order to further get a lager bandwidth, a modified Marchand balun is introduced for dual-band operation, which can provide two resonances in each band to enhance impedance bandwidth. By co-designing the radiating element with the dual-band balun, an antenna covering 2150-2750 MHz and 5050-6230 MHz has been achieved. The design equations for modified balun have been presented and agreement between calculations and measurements is good.
Novel Printed Yagi-Uda Antenna with Highgain and Broadband
Shu Lin;Guan-Long Huang;Run-Nan Cai;Jin-Xiang Wang
PIER Letters , 2011, DOI: 10.2528/PIERL10102804
Abstract: A high-gain and broadband printed Yagi-Uda antenna is proposed. The microstripline-to-balance microstripline technique is adopted in the feeding mode of the active dipole, which can help to realize the balanced-unbalanced transformation. The ground of the microstrip feeding line can function as a reflector, and both the longer reflector and the shorter director can also help the antenna achieve wideband. By altering the area of the substrate, the antenna gain can be effectively improved. A printed Yagi-Uda antenna operating at 3.5 GHz has been designed and manufactured. Both the simulated and measured results indicate that there is a high positive correlation between antenna gain and the substrate area extended from the front of the director, and antenna broadband characteristic would not be changed at the same time. Moreover, the impedance bandwidth of the proposed antenna can achieve 27.4%, and the maximum gain in the operating band can reach 10.6 dBi.
Wideband Omnidirectional Printed Dipole Antenna with Coupling Feed for Wireless Communication Applications
Zhi-Ya Zhang;Cheng-Bin Zhang
PIER C , 2013, DOI: 10.2528/PIERC13012010
Abstract: The wideband and omnidirectional performance of a printed dipole antenna with a novel coupling feed structure is presented. Besides using printed dipole for omnidirectional radiation patterns, the coupling feed structure, which includes the transmission line coupling to a slot line to effectively improve the impedance matching, can be used for bandwidth enhancement. A wideband impedance characteristic of about 45.6% for VSWR ≤2 ranging from 1.54 to 2.45 GHz is obtained. The omnidirectional radiation patterns in the whole operation bands are achieved which the un-roundness in H-plane is less than 1.6dB. It is sufficient for accommodating recent wireless communication services such as DCS1800, PCS1900, UMTS, IMT2000, Wibro, etc. Furthermore, the proposed antenna should be a good candidate as a unit of the omnidirectional array. A prototype has been fabricated and tested, and the experimental results validate the design procedure.
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