A 60 GHz Variable Gain Amplifier with a Low Phase Imbalance in 0.18 μm SiGe BiCMOS Technology

A 60GHz variable gain amplifier is designed and fabricated in 0.18 μm SiGe BiCMOS technology. A phase compensation technique is employed for the minimization of the phase imbalance at different gain states. With a 3.3 V supply, the amplifier achieves a variable gain ranging from -2.7 dB to 17.7 dB at 60 GHz, consuming DC power of 50 mW. The measured RMS phase imbalance is less than 2.8° at 57-66 GHz of the 60 GHz full band. The output 1-dB gain compression point is >; 2 dBm for all of the gain states at 60 GHz.