W -Band 6-Bit Active Phase Shifter Using Differential Lange Coupler in SiGe BiCMOS

This letter presents a W -band vector-modulator-based phase shifter with a 6-bit resolution, implemented in a SiGe:C BiCMOS technology. The phase shifter maintains the RMS amplitude and phase errors lower than 1 dB and 6.6 ^{\circ} , respectively, for the frequency range of 86-106 GHz without digital calibration. The maximum average gain is 2.3 dB with the 3-dB bandwidth achieving 31 GHz. The circuit consumes 49 mW of power including the phase control circuitry from a 2.4-V supply voltage, 34 mW of which is used by the Gilbert cell. A novel compact differential Lange coupler is used as an IQ splitter. The core part occupies only 0.027 mm ^2 of the chip area.