Tunable Wideband Amplifier at 180 GHz with 22 dB Gain and 40 GHz Bandwidth in 130 nm SiGe

This work presents an integrated, reconfigurable wideband amplifier for mm-wave applications. An internal tunable matching network enables dual-band gain compensation to achieve a flat frequency response. This is realized using individually biased and matched diodes as variable load for a 90° hybrid coupler. The approach is similar to a reflection-type phase shifter, resulting in the ability to change the effective input impedance throughout capacitive, resistive and inductive behavior. The circuit is designed for a center frequency of 180 GHz (G-band) and offers, after optimal tuning, a peak gain of 22 dB and a bandwidth of 41 GHz. The total power consumption is 65 mW, with an output referred 1-dB compression point of 1 dBm and an efficiency of 1.9%. The final chip occupies an area of 0.65 mm
²
and is implemented in a 130 nm SiGe BiCMOS process, offering a maximum oscillation frequency f
_max
of 450 GHz.