An ultra‐wideband power amplifier with band notched response

An ultra‐wideband (UWB) power amplifier (PA) integrated with notched structure is proposed in this letter. During the design process of the amplifier, a codesign approach was adopted, which realized an UWB band‐pass filter as the matching network, and a transmission zero was introduced within the passband to eliminate an interference to other radio systems. An example of band notch centered at 2.4 GHz was demonstrated in the PA. The measured results of the UWB amplifier are shown that 50% to 68% drain efficiency, 39.6 to 42.6 dBm output power, and higher than 10 dB power gain at the frequency range of 0.8 to 2.15 and 2.5 to 3 GHz are achieved. In addition, there is an obvious stopband of 2.2 to 2.4 GHz, and the minimum gain and output power in the stop band are 0.22 dB and 23 dBm, respectively.