A 220–280GHz InP Frequency Doubler with a Compact, Low-Loss Folded Marchand Balun

We present a 220–280 GHz indium phosphide (InP) push-push frequency doubler with a compact, folded Marchand Balun. The doubler generates a measured peak output power of 5 dBm and a peak conversion gain of -5 dB at 230 GHz, with an average output power of 3 dBm and conversion gain of -7 dB between 220–280 GHz. The peak power density is measured at 5.86 mW/mm², with a total die area of 0.54 mm². DC Power consumption peaks at 36 mW under saturation, resulting in peak DC-to-RF conversion efficiency of 8.8%.