28 GHz balanced pHEMT VCO with low phase noise and high output power performance for 5G mm-Wave systems

This paper presents the study and design of a balanced voltage controlled oscillator VCO for 5G wireless communication systems. This circuit is designed in monolithic microwave integrated circuit (MMIC) technology using PH15 process from UMS foundry. The VCO ensures an adequate tuning range by a single-ended pHEMT varactors configuration. The simulation results show that this circuit delivers a sinusoidal signal of output power around 9 dBm with a second harmonic rejection between 25.87 and 33.83 dB, the oscillation frequency varies between 26.46 and 28.90 GHz, the phase noise is -113.155 and -133.167 dBc/Hz respectively at 1 MHz and 10 MHz offset and the Figure of Merit is -181.06 dBc/Hz. The power consumed by the VCO is 122 mW. The oscillator layout with bias and RF output pads occupies an area of 0.515 mm2

Design of a Ku-band low-phase-noise VCO using the dual LC tanks

A Ku-band voltage-controlled oscillator (VCO) using dual tanks, together with feedback, is proposed and designed by using a 0.18-μm Bipolar compatible Complementary Metal Oxide Semiconductor (BiCMOS) process. A triple-coil transformer is employed to provide strong coupling between the two tanks and simultaneously introduce a transformer-based feedback. The parameters of the transformer are optimized to provide the required inductance ratios and reduce unwanted parasitic. The phase noise improvement for the proposed VCO is analyzed theoretically and verified by circuit and full-wave electromagnetic simulators. A benefit from the strong coupling between the two tanks, the proposed VCO achieves a low phase noise of -117.4 dBc/Hz at 1-MHz offset from an operation frequency of 12.64 GHz with a 4.3-mW power consumption of the VCO core