A 200 Wbroadband high power amplifier using hybrid power combining network and digital level control

摘要

In this article, a 2 to 6 GHz solid-state power amplifier with 53 dBm outputpower has been analyzed, designed, and fabricated. To achieve a widebandhigh output power, we introduce a 16-way hybrid power combiner based onmicrostrip planar binary and parallel structures. The simulation and measurementresults of the proposed hybrid power combining network (PCN) showthat the maximum power combining efficiency is around 86% with the insertionloss of around 0.6 to 1.5 dB and an isolation of 20 dB between the ports.Also, to compensate the output power variations due to the thermal and operatingfrequency changes across the bandwidth, a digital level control (DLC)unit utilizing an agile control algorithm is proposed which decreases the outputpower variations to 2% of the desired output power. A cooling heatsink fansystem has been also designed in order to transfer the heat generated power tothe air. The measured output power for the applied input continuous wave ishigher than 52.5 dBm. In addition, the power added efficiency (PAE) is betterthan 15% across the wide portion of the bandwidth and the measured thirdorderintermodulation is about 20 dBc (average).