A quadrature sinusoidal oscillator with phase-preserving linear frequency control and independent static amplitude control

A G_m-C architecture for a quadrature, sinusoidal oscillator with instantaneous, phase-preserving, linear frequency control and independent, static amplitude control is presented. The architecture is analyzed and closed-form expressions are given for both frequency and amplitude. An implementation of the architecture using general purpose discrete bipolar transistors has been tested. Simulation results and measurements are demonstrated and compared to theory. The wide frequency range of tunability and the low total harmonic distortion observed, as well as the inherent phase preservation make the architecture appropriate for use in analog communication schemes