Characterizing Digitally Modul...

Characterizing Digitally Modulated Signals with CCDF CurvesCharacterizing Digitally Modulated Signals with CCDF Curves

Application Note

Table of Contents
1. Introduction When are CCDF curves used? 2. What are CCDF curves? Statistical origin of CCDF curves Why not crest factor? 3. CCDF in communications Modulation formats Modulation filtering Multiple-frequency signals Phases affect multi-tone signals Spread-spectrum systems Number of active codes in spread spectrum Orthogonal coding effects Multi-carrier signals 4. CCDF in component design Compression of signal by nonlinear components Correlating the amplifier curves with the CCDF plot Compression affects other key measurements Applications 5. Summary 6. References 7. Symbols and acronyms

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Introduction
Digital modulation has created a revolution in RF and microwave communications. Cellular