volume | PIER Journals

Abstract

Modern wireless systems require filters that can tune multiple bands independently, but conventional designs cannot achieve this and suffer from limited flexibility and higher loss. The proposed filter solves this problem by providing compact, low-loss, and independently reconfigurable dual-band operation for multi-standard applications. Therefore, in this paper, a reconfigurable substrate-integrated waveguide bandpass filter is proposed. The filter is suitable for a broad range of wireless applications. The first band has a centre frequency of 2.7 GHz and attains a tuning percentage of 13.4%. The second band achieves 26.35% at a centre frequency of 4.7 GHz. The lower band targets S-band applications, whereas the upper band is appropriate for 5G band n79 applications and can be reconfigured to cover the C-band. The proposed design has complementary split-ring resonator slots on the top layer with four p-i-n diodes. It has compact dimensions of 0.21λ_g × 0.48λ_g, a minimal insertion loss of less than 1 dB, and a substantial return loss of 14 dB. Advanced design methods, including eigenmode analysis, are used to attain precise selectivity and computation of the coupling matrix. The filter demonstrates superior performance and guarantees low interference, with suppression up to 9 GHz. A prototype filter was fabricated and measured, with the results closely agreeing with the simulations.

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Dr. Amjad A. Al-Rahmah

Dr. Bashar J. Hamza