In this letter, a tunable quasi-reflectionless filtering antenna is proposed. The device consists of a reflective microstrip bandstop filter (BSF) and a radiating patch antenna connected in a complementary-duplexer fashion. By terminating the output port of the BSF with another antenna and employing the patch antenna (antenna channel) as the radiator, a tunable quasi-reflectionless antenna is obtained. Since each element works at a specific frequency, the antenna array distributes spectrum resources to different antenna elements, which fits with the multicarrier base station application. The theoretical analysis by equivalent circuits is given. For verification, a dual-band prototype is fabricated and measured. The measured results agree well with the simulation. The filtering antenna exhibits a fractional bandwidth of 3.2% and a tuning range from 3.6 to 4.1 GHz for each band. The maximum radiation gain is 5.5 dBi, making it a good candidate for a multicarrier transceiver in sub-6 GHz 5G applications.

中文翻译：

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用于多载波收发器的准无反射可调谐滤波天线


在这封信中，提出了一种可调谐准无反射滤波天线。该器件由以互补双工器方式连接的反射微带带阻滤波器 (BSF) 和辐射贴片天线组成。通过在BSF的输出端口端接另一天线并采用贴片天线（天线通道）作为辐射器，获得可调谐准无反射天线。由于每个单元工作在特定的频率，天线阵列将频谱资源分配给不同的天线单元，这适合多载波基站应用。给出了等效电路的理论分析。为了进行验证，制造并测量了双频带原型。测量结果与模拟结果非常吻合。滤波天线的分数带宽为 3.2%，每个频段的调谐范围为 3.6 至 4.1 GHz。最大辐射增益为 5.5 dBi，使其成为 6 GHz 以下 5G 应用中多载波收发器的良好候选者。