High performance Lowpass Filter using Tetramerous Radial Stubs

This paper introduces a novel microstrip lowpass filter characterized by several remarkable features, including a sharp roll-off, extensive stopband, minimal insertion loss, compact dimensions, and high return loss, all achieved through the innovative use of tetramerous radial stub resonators. The transition band of the filter spans approximately ۰.۳۱ GHz, ranging from ۱.۹۶ to ۲.۲۷ GHz, with notable attenuation levels of −۳ dB and −۴۰ dB at the respective edges. Additionally, the stopband extends impressively from ۲.۲ GHz to ۲۲ GHz, achieving attenuation greater than ۲۰ dB, which ensures effective signal suppression outside the desired frequency range. In the passband, the insertion loss is exceptionally low, remaining below ۰.۱ dB, while the return loss exceeds ۱۹.۸۹ dB, indicating excellent matching characteristics. Furthermore, the total area of the filter measures a compact ۱۸۹ mm², making it suitable for space-constrained applications. The proposed design has been fabricated and tested, with results from simulations and measurements demonstrating strong correlation and validating its performance.

کلیدواژه ها:

low insertion loss ، lowpass filter ، tetramerous radial stubs resonator ، ultra wide stopband