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Explains the Peak to Average Power Ratio (PAPR) and shows why it is important for OFDM digital communications. Sometimes this is also called Peak to Average Ratio (PAR).
Related videos: (see iaincollings.com)
• OFDM Waveforms • OFDM Waveforms
• OFDM and the DFT • OFDM and the DFT
• What is a Cyclic Prefix in OFDM? • What is a Cyclic Prefi...
• How does OFDM Overcome ISI? • How does OFDM Overcome...
• How are OFDM and xDSL (DMT) Related? • How are OFDM and xDSL ...
• What are Channel Capacity and Code Rate? • What are Channel Capac...
• What is Water Filling for Communications Channels? • What is Water Filling ...
Full categorised list of videos with PDF Summary Sheets: iaincollings.com
Note that when discussing the OFDM case (top right hand drawing showing the five waveforms), I wanted to keep the diagram simple, so that I could explain the "phase alignment" problem, so I didn't draw waveforms for all the carriers. I probably should have mentioned it, but I only drew waveforms for the following multiples of the base frequency: 1, 2, 4, 8, 16. It was too complicated to draw all the other multiples (3, 5, 6, 7, 9, 10 ...). Also note that the diagrams I showed are "baseband". In other words, I didn't show them after they are up-converted to the carrier frequency
.