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Improved \(Q\)-Factor Calculations for Single Port Filter-Antenna Measurement

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Abstract

These days most of the research work in the area of filter-antenna design is focused on having high quality factor for certain frequency band. These type of filter-antennas are difficult to design as the design engineers are required to have low quality factor for the radiating band of frequency. Hence a precise value of \(Q\)-factor is required to understand the radiating and filtering properties of filter-antennas. Filter-antennas are single port devices as the second port is considered as radiating port. Return loss is used, in order to yield \(Q\)-factor through calculations for such devices. However, the conventional method for calculating \(Q\)-factor found to be inaccurate in most of the low \(Q\)-factor cases. This paper proposes a method that out performs the conventional method of calculating \(Q\)-factor. Non-ideal fabrication process is also discussed for accurate evaluation of \(Q\)-factor. Experimental results show that proposed method can be employed to calculate \(Q\)-factor with reasonable accuracy for simulated and measured results.

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Authors and Affiliations

  1. COMSATS Institute of Information Technology, Park Road, Chak Shahzad, Islamabad, Pakistan

    Khurram Saleem Alimgeer, Shahid A. Khan & Shahzad A. Malik

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  1. Khurram Saleem Alimgeer
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  2. Shahid A. Khan
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  3. Shahzad A. Malik
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Correspondence to Khurram Saleem Alimgeer.

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Alimgeer, K.S., Khan, S.A. & Malik, S.A. Improved \(Q\)-Factor Calculations for Single Port Filter-Antenna Measurement. Wireless Pers Commun 72, 1351–1359 (2013). https://doi.org/10.1007/s11277-013-1082-3

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  • DOI: https://doi.org/10.1007/s11277-013-1082-3

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