volume | PIER Journals

Abstract

A highly compact bandpass filter (BPF) is designed with a capacitively-coupled compact ring resonator. The ground plane is perturbed with a combination of two inter-digital and two spiral defected ground structures (DGSs), which enhance the selectivity and suppress the higher order harmonics of the BPF respectively. The filter has a selectivity of 0.22 dB/MHz, passband insertion loss (IL) of 1.55 dB and bandwidth of 61 MHz at 2.53 GHz. The proposed compact ring resonator yields a size reduction of 70.5% compared to a conventional ring resonator. This BPF is significant for wireless telemetry monitoring systems for physiological parameters including electrocardiogram (ECG), electroencephalography (EEG) and electromyography (EMG) using portable devices.

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Dr. Yang Yang

Dr. Sushim M. Roy

Dr. Nemai C. Karmakar

Dr. Xi Zhu