The Research Of A Digital Fractional Frequency Synthesizer Based On △-∑ Modulation

This paper discusses an innovative fractional frequency synthesizer based onΔ-Σmodulation techniques. TheΔ-ΣModulation Technology is an advanced method developed with digital processing technology. The principle is to move the phase noise to the high spectrum by modulating the divider ratio ofΔ-Σmodulation, thus, the phase noise can be filter effectively by low-pass loop filter. The kye technology is the use of first-orderΔ-ΣModulation in the frequency discriminator, additionally, to compensate for quantization error with digital method in order to restrain the fractional clutter.This paper mainly describs the theory of digital fractional frequency synthesizer base onΔ-Σmodulation, the synthesizer has been realized and the important data is measrued. Firstly, paper introduces the theory ofΔ-ΣModulation; secondly, the synthesizer's overview is prsent, the design of the digital fractional frequency synthesizer base onΔ-Σmodulation will be introduced in detail; lastly, the demo model is achieved and the experimental data are provided.