"JOURNAL OF RADIO ELECTRONICS" (Zhurnal Radioelektroniki ISSN 1684-1719, N 4, 2019

contents of issue      DOI  10.30898/1684-1719.2019.4.13     full text in Russian (pdf)  

UDC 621.396

Methods of dealing with interference in PLL frequency synthesizers

P. A. Tolkachev
MIREA – Russian Technological University, Vernadsky av. 78, Moscow, 119454, Russia

The paper is received on March 14, 2019


Abstract. Research questions of the frequency synthesizer with a divider with a variable and a fractional variable division factor are considered. The term fractional-N describes a family of synthesizers that allow the minimum frequency step to be a fraction of the reference frequency. A number of methods have been proposed to realize fractional-N frequency synthesis, they are based on the basic concepts of traditional integer-N synthesis. The problems of adverse components in the spectrum of the output signal of fractional-N synthesizers are revealed. There are two methods of increasing the quality of the output signal of the PLL frequency synthesizers of synthesis methods to improve the spectrum of output signal for PLL frequency synthesizers synthesis. The first method is random jittering, the second is phase cancellation method. The correctness of the methods is checked using simulation in the software package Simulink.

Keywords: frequency synthesizer of the indirect synthesis; fractional variable division ratio; method of randomization of switching coefficients; method of phase error correction, fractional frequency synthesizer simulation.


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For citation:

P. A. Tolkachev. Methods of dealing with interference in PLL frequency synthesizers. Zhurnal Radioelektroniki - Journal of Radio Electronics. 2019. No. 4. Available at http://jre.cplire.ru/jre/apr19/13/text.pdf

DOI  10.30898/1684-1719.2019.4.13