Title :
Optimal dithered digital sigma-delta modulators for fractional-N frequency synthesizers
Author :
Gonzalez-Diaz, Victor Rodolfo ; Garcia-Andrade, Miguel Angel ; Flores-Verdad, Guillermo Espinosa
Author_Institution :
Nat. Inst. for Astrophys., Opt. & Electron., Puebla
Abstract :
By using a structured dither addition it is demonstrated how a very simple 8-bit linear feedback shift register (LFSR) can be used to randomize a digital MASH 1-1-1 SigmaDelta modulator used for fractional-N frequency synthesizers. With this optimization, spur tones for high frequency offset from the carrier are avoided without significant area and power budget increase.
Keywords :
delta-sigma modulation; frequency synthesizers; shift registers; digital MASH 1-1-1 sigma-delta modulator; fractional-N frequency synthesizers; linear feedback shift register; optimal dithered digital sigma-delta modulators; structured dither addition; Degradation; Delta-sigma modulation; Digital modulation; Frequency modulation; Frequency synthesizers; Multi-stage noise shaping; Noise shaping; Phase noise; Quantization; Topology;
Conference_Titel :
Circuit Theory and Design, 2007. ECCTD 2007. 18th European Conference on
Conference_Location :
Seville
Print_ISBN :
978-1-4244-1341-6
Electronic_ISBN :
978-1-4244-1342-3
DOI :
10.1109/ECCTD.2007.4529658
