A K-Band 5W Doherty Amplifier MMIC Utilizing 0.15µm GaN on SiC HEMT Technology

The design and performance of a K-Band Doherty amplifier MMIC is presented. The monolithic 2-stage amplifier was fabricated with a dual field plate 0.15um GaN on SiC HEMT process technology. Measured continuous wave results at 23GHz demonstrate over 5W of saturated output power and up to 48% power added efficiency. Peak efficiency occurs at approximately 1dB of gain compression and the amplifier maintains 25% power added efficiency at 8dB of input power back off from P1dB.

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