A Ku-band CMOS 6-bit Digital-Controlled Phase-Invariant Variable Gain Amplifier and Attenuator

This paper presents a 6-bit CMOS digital-controlled gain-tuning building block in phased array. The proposed building block combines a 15-dB-tuning phase-invariant variable gain amplifier (VGA) with a 15-dB-tuning attenuator (ATT). Thus, 30-dB tuning range and 0.5-dB resolution with <; 4.6° RMS phase variation are achieved in the designed frequency range (10.5 GHz-13 GHz).