Realization of Miniatured Wi-Fi 6E Bandpass Filters on a Low-Loss Organic Substrate

In this study, miniaturized Wi-Fi 6E bandpass filters (BPFs) with asymmetrical frequency response were developed on a low-loss organic substrate. The cross-coupling technique can be used to generate one or two transmission zeros (TZs) on the lower side of the passband, thus producing an asymmetrical frequency response. This response is effective for avoiding interference in Wi-Fi 6E communication systems. To validate the aforementioned approach, a fourth-order planar BPF and a fifth-order multilayer BPF were designed and fabricated using microstrip technology. To miniaturize the circuit, multilayer printed circuit board manufacturing technology was employed to realize the fifth-order BPF. The experimental and simulated results were in favorable agreement. Compared with other BPFs designed in recent works, the proposed BPFs have numerous advantageous features, such as their compact size, sharp roll-off rate (ROR), high stopband attenuation, and simple layout.