The fully integrated GaInP/GaAs heterojunction bipolar transistor, transformer-based top-series quadrature voltage controlled oscillator (QVCO) is demonstrated at 4 GHz. The transformers on the semi-insulating GaAs substrate possess good electrical properties at high frequencies. The QVCO at 4.1 GHz has phase noise of -120 dBc/Hz at I MHz offset frequency, output power of 2 dBm and the figure of merit -178 dBc/Hz.
- GaInP/GaAs heterojunction bipolar transistor (HBT)
- Phase noise
- Quadrature voltage controlled oscillator (QVCO)
- Top-series coupling