Signal-to-noise Ratio Improvement of a FM Antenna Using a Non-Foster Circuit

Non-Foster 회로를 이용한 FM 안테나의 신호 대 잡음비 개선

Park, Hongwoo;Kahng, Sungtek;Kim, Hongjoon

  • Received : 2015.11.30
  • Accepted : 2016.01.14
  • Published : 2016.02.01


In this paper, we demonstrate a Non-Foster matching method for an electrically small antenna to improve the signal-to-noise ratio (SNR) of communication link. For the experiment, we used a general FM antenna whose resonance frequency is about 52-57 MHz and a floating type Linvill negative impedance converter(NIC)-based circuit as a Non-Foster matching element. By implementing the Non-Foster circuit to cover FM band, we can achieve a wide bandwidth matching covers 40-200 MHz. Our measurement shows 3-7 dB improvement of SNR for the same bandwidth though there are several spikes which means no improvement of SNR in the band.


Broadband matching;Non-foster impedance matching;Negative impedance converter;FM antenna;Signal-to-noise ratio improvement


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Supported by : National Research Foundation of Korea (NRF), Ministry of Science, ICT and Future Planning