30% PAE W-Band InP Power Amplifiers Using Sub-Quarter-Wavelength Baluns for Series-Connected Power-Combining

We present high-efficiency W-band power amplifier (PA) ICs with a new series-connected power combining technique using sub-quarter-wavelength transmission- line baluns. The PAs are implemented in a 0.25μm InP HBT process. At 86GHz, a single-stage PA exhibits 30.4% peak PAE, 20.37dBm P
_out
and 23GHz 3dB bandwidth. A two-stage PA exhibits 30.2% PAE, and 23.14dBm P
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. These values of PAE represent a 1.2:1 improvement in the state-of-the-art for E- and W- band PAs having similar RF output powers.