volume | PIER Journals

Abstract

In this paper, we propose a method to reduce the length of the narrowband microstrip Uniform Coupled Transmission Lines (UCTLs), which has a general application to compact microstrip circuits. In this method, we use Nonuniform Coupled Transmission Lines (NCTLs) instead of UCTLs. To synthesize the desired NCTLs, their normalized width and gap are expanded as two truncated Fourier series. Then, the optimal values of the coefficients of the series are obtained through an optimization approach. The usefulness of the proposed method is verified using some examples. Also, an edged-coupled bandpass filter is compacted using the proposed method and then is fabricated and measured.

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Dr. Mohammad Khalaj-Amirhosseini

Dr. Ali H.Tehrani