A Linear Voltage Controlled Quadrature Oscillator

A linear voltage controlled quadrature oscillator (LVCQO) is presented; the design uses commercially available IC modules. The response had been experimentally verified with simulation and hardware test. The realization is based on an electronically tunable allpass filter (ETAF) coupled with a voltage controlled integrator (VCI). Quadrature oscillator tuning frequecy is measured in a range of with satisfactory phase-noise response of -96 dBc/Hz. Effects of device parasitic are negligible.