Low phase noise K-band VCO and high efficiency E-band power amplifier for mobile network backhaul in SiGe BiCMOS

The mobile communication infrastructure is evolving toward small- and pico-cell networks, enabling higher channels capacity and user data-rate. This is motivating development of mmWave silicon transceivers for backhaul, and BiCMOS represents an optimal compromise between cost and performance. This paper proposes a Voltage Controlled Oscillator (VCO) and Power Amplifier (PA) suited for of E-band backhaul. Circuit topologies exploit the benefits of an advanced 55nm BiCMOS technology, fulfilling system requirements with low power consumption. The Class-C VCO features a state-of-the-art minimum phase noise of −119dBc/Hz at 1MHz offset from 20GHz with 55mW only. The PA is based on a common-base output stage leveraging current clamping to scale the DC current with Pout, keeping high power added efficiency (PAE) in back-off. Psat at 80GHz is 19dBm and OP1dB is 18dBm. The PAE at OP1dB and 6dB back-off is 22% and 8.5% respectively, at least ∼2x higher than reported E-band silicon PA at comparable Pout.