Three-Points Modulator Based on DPLL for Wideband Polar Modulation

Julien Kieffer, Sébastien Rieubon, Marc Houdebine, Sébastien Dedieu, Emil Novakov

IMEP-LAHC, University of Grenoble-Alpes, Grenoble, France.
ST-Ericsson, Grenoble, France.
STMicroelectronics, Crolles, France.

DOI: 10.4236/cn.2013.53B2027                

Abstract

We present a nonlinear event-driven model of a Digital PLL used in the context of a polar modulation. This modeling has shown that the estimation method of the TDC gain has a big impact on the EVM for wideband modulation and a solution has been proposed which consists to add the modulation on the gain after calibration of the gain offset. This transforms the classical two-points modulator into a three-points modulator. This implementation has been validated for WCDMA standard.

Keywords

DPLL; Polar Modulation; WCDMA; TDC

Conflicts of Interest

The authors declare no conflicts of interest.

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