Novel Compact UWB Bandpass Filters Design With Cross-Coupling Between lambda/4 Short-Circuited Stubs

作者：Li Xiuping^*; Ji Xiang

来源：IEEE Microwave and Wireless Components Letters, 2014, 24(1): 23-25.

DOI：10.1109/LMWC.2013.2287231

• Bandpass filters (BPFs)
• cross coupling
• lambda/4 short-circuited stubs
• transmission zeros
• ultra-wideband (UWB) filter

Two novel, compact, and highly frequency selective ultra-wideband (UWB) bandpass filters (BPFs) based on an improved model are presented in this letter. The improved model contains four short-circuited stubs connected by transmission lines. A cross-coupling between the first and last short-circuited stubs is introduced to obtain new pairs of transmission zeros on both sides of the passband. The relationship between the coupling factor and the position of the transmission zeros was analyzed and good agreement was obtained between the analysis and model simulation results. Based on the model, two UWB BPFs are designed with 51% (3.1 to 5.2) GHz and 108% (3 to 10) GHz relative bandwidth and small size of 15 mm 15 mm and 19 mm 14 mm, respectively. The insertion loss of the (3.1 to 5.2) GHz filter is less than 0.4 dB in passband and the other one is less than 3 dB. The simulation and measurement results agree well.

• 出版日期2014-1
• 单位北京邮电大学