Low Phase Noise 10GHz DRO with low 1/f noise SiGe HBTs

SiGe HBTs are ideal devices for low phase noise microwave oscillators as they combine high cutoff frequencies with low 1/f noise. A hybrid 10GHz dielectric resonator oscillator has been built using discrete SiGe HBT chips. The low frequency noise and the phase noise of the circuit were measured and compared. The value of ¿118 dBc at 10 kHz off carrier was probably the resolution limit of the measurement setup. These silicon-based devices largely outperform III/V HBTs and they offer the additional advantage of much lower costs.