Three point modulated phase locked loop frequency synthesis system and method

The present invention relates to a frequency modulated system, and a method for operating same, including a phase locked loop frequency synthesizer circuit which synthesizes a carrier frequency through the use of an electronically controlled oscillator. The circuit, which has a certain loop bandwidth, includes a reference frequency source and a bypassed correcting integrator. A modulating signal simultaneously modulates the oscillator, the reference frequency source and the bypassed correcting integrator such that the carrier frequency is frequency modulated with a certain frequency deviation. The magnitude of the modulation of the oscillator, the reference frequency source and the correcting integrator are controlled over a frequency range by frequency blending the reference frequency source and the bypassed correcting integrator such that low distortion modulation over a wide frequency range is achieved.