Title :
Phase noise improvement in fractional-N synthesizer with 90° phase shift lock
Author :
Park, Joohwan ; Maloberti, Franco
Author_Institution :
Dept. of Electr. Eng., Texas Univ., Dallas, TX, USA
Abstract :
An effective technique for phase noise improvement in a fractional-N synthesizer is described. The method requires using, in a 90° phase shift lock, a non-linear continuous-time or sampled-data block before the loop filter. Behavioral simulations on a fractional-N synthesizer incorporating different non-linear blocks, and a second-order single bit sigma delta modulator, show that it is possible to achieve phase noise improvements at medium frequency as good as 17 dB.
Keywords :
circuit noise; circuit simulation; frequency synthesizers; network synthesis; nonlinear network analysis; phase detectors; phase locked loops; phase noise; sampled data circuits; sigma-delta modulation; 1 bit; PLL; fractional-N synthesizer; frequency synthesizer; loop filter; nonlinear continuous-time block; nonlinear sampled-data block; phase detector; phase shift lock; sigma delta modulator; synthesizer phase noise improvement; Bandwidth; Capacitors; Charge pumps; Filters; Laser mode locking; Phase locked loops; Phase noise; Synthesizers; Voltage control; Voltage-controlled oscillators;
Conference_Titel :
Circuits and Systems, 2003. ISCAS '03. Proceedings of the 2003 International Symposium on
Print_ISBN :
0-7803-7761-3
DOI :
10.1109/ISCAS.2003.1205668
