Conference Paper

Requirements for Time-to-Digital Converters in the context of digital-PLL based Frequency Synthesis and GSM Modulation

Linz Center of Mechatronics GmbH
DOI: 10.1109/MWSYM.2006.249748 Conference: Microwave Symposium Digest, 2006. IEEE MTT-S International
Source: IEEE Xplore

ABSTRACT

A key issue in proceeding the digitization of phase-locked loops (PLLs) is the realization of proper phase detectors in the digital domain. This paper presents simulative analysis of the properties and requirements for time-to-digital converters (TDCs) used for phase comparison in digitized fractional-N modulators with two-point modulation. Effects due to quantization of the TDC on frequency synthesis as well as GSM modulation quality are considered, defining the realization requirements for a transmitter

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