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Zhuhai, China

Fei P.,National Laboratory of Science and Technology on Antennas and Microwaves | Qi Y.,DBJ Technologies | Jiao Y.,National Laboratory of Science and Technology on Antennas and Microwaves
Progress in Electromagnetics Research | Year: 2013

In this paper, a wide slot loop antenna with an adjustable back-reflector is introduced. Five working statuses are defined by simply adjusting the distances between the radiator and the reflector. Measured results show the total available operating band with better than 10 dB return loss ranges from 0.84 GHz to 3.04 GHz (113.4%). The radiation properties of the array are tested in an anechoic chamber. Stable unidirectional radiations with more than 8.3 dB gains are observed in the working band. Apart from that, the straightforward two-portion arrangement of the design provides cost effective solution for mass production. All these features make the antenna an appropriate substitute for multiple narrowband antennas. Source

Liu Z.,Hunan University | Li F.,Hunan University | Qi Y.,DBJ Technologies | Chen J.,University of Houston
2015 IEEE Symposium on Electromagnetic Compatibility and Signal Integrity, EMCSI 2015 | Year: 2015

Radio sensitivity sweep is a required for regulatory certification and radio research and development (R&D). For radio R&D, the accuracy and speed of the measurement can affect the quality, cost and time to the market for a product. The traditional receiver sensitivity measurement method is a lengthy process using power stepping procedure. In this paper, we propose a novel technique of using the shape invariance of sensitivity curve in frequencies to speed up the radio sensitivity sweep test. The theoretical foundations of our method are discussed and the actual experimental procedure and interference elimination are also described in this paper. © 2015 IEEE. Source

Lin F.,Xidian University | Qi Y.,DBJ Technologies | Qi Y.,Missouri University of Science and Technology | Jiao Y.-C.,Xidian University
IEEE Antennas and Wireless Propagation Letters | Year: 2013

This letter presents a bilateral tapered slot antenna (BTSA) as a measurement antenna for electromagnetic compatibility (EMC) and antenna measurements. By virtue of the proposed wideband 50-$\Omega$ feeding transition and carefully adjusted tapered slot profile, together with the truncation compensation method, the proposed BTSA maintains a single main beam in the radiation pattern across the entire operating frequency band from 700 MHz to 20 GHz rather than main-beam split above 12 GHz, which is suffered by most traditional horn antennas and tapered slot antennas. Also, better than 25 dB cross-polarization level and less than 2:1 VSWR are obtained within the frequency band of interest. The validity of the proposed design is verified experimentally. The proposed BTSA can be applied to EMC and antenna measurement systems or further employed to construct a dual-polarized BTSA for other measurement applications. © 2002-2011 IEEE. Source

Gao X.,Xidian University | Qi Y.,Xidian University | Jiao Y.-C.,DBJ Technologies | Jiao Y.-C.,Missouri University of Science and Technology
IEEE Antennas and Wireless Propagation Letters | Year: 2013

A novel multiplate back-reflector wide-bandwidth unidirectional slot antenna is presented in this letter. The proposed structure not only maintains the wideband nature of slot structure, but also exhibits stable antenna gain and better front-to-back (F/B) ratio over the frequency band of interest. A slot antenna consisting of a pair of matching disc patches and a microstrip feeding line is employed to demonstrate the advantages of the new reflector structure. Four smaller metallic plates in different distances are used. Initial parameter measurement of the new slot antenna is conducted. The result shows an impedance bandwidth can exceed the original slot antenna bandwidth for S 11≤-10dB in the range 1.56-3.14 GHz, stable gain more than 8.5 dB, and F/B ratio higher than 17 dB, with unidirectional radiation patterns and low cross polarization over the whole operating band. Those performances are exceeding the performance that a conventional back-reflector slot antenna can obtain. © 2002-2011 IEEE. Source

Lin F.,Xidian University | Jiao Y.-C.,Xidian University | Qi Y.,DBJ Technologies | Qi Y.,Missouri University of Science and Technology
IEEE Microwave and Wireless Components Letters | Year: 2013

A microstrip to bilateral slotline (BS) transition is proposed in this letter, which contains a 50-Ω constant impedance BS and a heart-shaped slotline cavity. Unlike traditional slotline transitions, the proposed transition does not suffer from matching issues when losses are incurred by multi-section impedance transformers and this transition has a potential to operate from 530 MHz to over 20 GHz if a K-connector is used. This letter will illustrate the discovery of BS with constant impedance first and then its application in design of the 50-Ω BS. The heart-shaped slotline cavity is proposed for bandwidth improvement. And the transition size is also reduced due to the absence of multi-section impedance transformers. A prototype is fabricated and measured to demonstrate this concept of the design, and it has a practical operating bandwidth from 0.53 to 12.23 GHz (about 23:1) with return loss better than 10 dB and insertion loss less than 3 dB. © 2001-2012 IEEE. Source

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