• 한국ITS학회 논문지
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• 제10권4호
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• pp.65-70
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• 2011

본 논문에서는 PIFA(Planer Inverted F Antenna)와 IFA(Inverted F Antenna)를 결합한 스마트 폰과 같은 데이터통신 단말기용 안테나를 설계하고 이를 제작하였다. 1개의 급전구조를 가지면서 PIFA와 IFA가 동시에 동작하도록 함으로써 다중대역특성을 갖도록 하였다. 베어보드에 제작된 안테나는 GSM900/USPCS/WCDMA 대역에서 VSWR 3:1 특성을 만족하였다. 평균이득과 효율은 GSM900 대역에서 -2.19~-3.63 dBi 및 43.31~60.33 %가 측정되었다. 또한 USPCS /WCDMA 대역에서는 -2.16~-10.67 dBi 및 8.56~60.78 %의 효율특성을 갖는다.

• Journal of electromagnetic engineering and science
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• 제16권3호
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• pp.169-181
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• 2016

This work presents a new method for enhancing the performance of a dual band Planer Inverted-F Antenna (PIFA) and its lumped equivalent circuit formulation. The performance of a PIFA in terms of return loss, bandwidth, gain, and efficiency is improved with the addition of the proposed open stub in the radiating element of the PIFA without disturbing the operating resonance frequencies of the antenna. In specific cases, various simulated and fabricated PIFA models illustrate that the return loss, bandwidth, gain, and efficiency values of antennas with longer optimum open stub lengths can be enhanced up to 4.6 dB, 17%, 1.8 dBi, and 12.4% respectively, when compared with models that do not have open stubs. The proposed open stub is small and does not interfere with the surrounding active modules; therefore, this method is extremely attractive from a practical implementation point of view. The second presented work is a simple procedure for the development of a lumped equivalent circuit model of a dual band PIFA using the rational approximation of its frequency domain response. In this method, the PIFA's measured frequency response is approximated to a rational function using a vector fitting technique and then electrical circuit parameters are extracted from it. The measured results show good agreement with the electrical circuit results. A correlation study between circuit elements and physical open stub lengths in various antenna models is also discussed in detail; this information could be useful for the enhancement of the performance of a PIFA as well as for its systematic design. The computed radiated power obtained using the electrical model is in agreement with the radiated power results obtained through the full wave electromagnetic simulations of the antenna models. The presented approach offers the advantage of saving computation time for full wave EM simulations. In addition, the electrical circuit depicting almost perfect characteristics for return loss and radiated power can be shared with antenna users without sharing the actual antenna structure in cases involving confidentiality limitations.