Analysis on wideband band pass filter microwave sensor performances for measuring rice quality in agriculture industry

Abstract

This paper introduced the analysis of three microstrip band pass filter designs which can work as a microwave resonator/sensor to measure the quality of rice. To maintain the tight coupling for over a wideband frequency range, all of the designs implemented broad-side coupling microstrip-slot tech-nique into the design. The analysis shows that band pass filter Type 2 has the best performance com-pared to the other two designs; where the return loss is -25.3 dB and insertion loss is -0.1 dB. This is due to the signal that can transfer effectively in the ring-shaped patch (comparing Type 1 with Type 2 and Type 3) and with thicker ring (comparing Type 2 and Type 3). The advantage of using the wide-band band pass filter as a microwave resonator/sensor is compact in size and low manufacturing cost.