Investigation of device low frequency noise in 28 GHz MMIC VCO

This paper reports on the LF noise spectra for 0.2 /spl mu/m gate length GaAs HEMTs based on a combined enhancement/depletion process manufactured by Philips Microwave Limeil ED02AH. The LF noise is used for an extended large signal model of the transistor implemented in a 28 GHz MMIC VCO. Flicker noise and g-r related noise are included in the phase noise simulation and thus the oscillator phase noise calculations, considering the all important LF noise contributions, are taken into account. The results show that the LF noise (1 kHz -100 kHz) being upconverted controls the phase noise performance of AlGaAs-GaAs HEMT oscillators.