PLL and Costas loop based carrier recovery circuits for 4QAM: non-linear analysis and simulation

N. V. Kuznetsov; J. Ladvanszky; M. V. Yuldashev; R. V. Yuldashev

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arXiv · 1810.00071

PLL and Costas loop based carrier recovery circuits for 4QAM: non-linear analysis and simulation

N. V. Kuznetsov·J. Ladvanszky·M. V. Yuldashev·R. V. Yuldashev

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Abstract

Design of stable carrier recovery circuits are used in many applications: wireless digital communication, optical communication, microwave devices and other applications. Quadrature Phase-Shift Keying (QPSK, 4-QAM) is used as modulation technique in many of these applications, since QPSK provides double the data rate of classic Binary PSK (BPSK) modulation. Analysis of Costas loop is a hard task because of its non-linearity. In this work we consider two well-known modifications of 4QAM Costas loop circuits and discuss a new circuit proposed by J. Ladvanszky. MATLAB Simulink models of the circuits are provided and the noise analysis is performed.

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BibTeX RIS

N. V. Kuznetsov, J. Ladvanszky, M. V. Yuldashev, R. V. Yuldashev. 2018-09-28. PLL and Costas loop based carrier recovery circuits for 4QAM: non-linear analysis and simulation. https://arxiv.org/abs/1810.00071

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