In this paper, a compact band-stop filter with a wideband and high-selectivity performance is proposed and analyzed. This band-stop filter includes two parallel-coupled lines of different electrical lengths and two open-circuit stubs. A lossless transmission line model is used to obtain the filter design parameters. In order to verify this new filter circuit structure and its corresponding design theory, five groups of numerical examples are demonstrated. Finally, a practical band-stop filter with a 3-dB cutoff frequency bandwidth of 58.2% centered at 0.94 GHz has been designed, simulated and measured. The measured results show a good agreement with the simulated responses.
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