What is PAPR? and its relationship to OFDM

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 http://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 Prefix in OFDM?  
• How does OFDM Overcome ISI?    • How does OFDM Overcome ISI?  
• How are OFDM and xDSL (DMT) Related?    • How are OFDM and xDSL (DMT) Related?  
• What are Channel Capacity and Code Rate?    • What are Channel Capacity and Code Rate?  
• What is Water Filling for Communications Channels?    • What is Water Filling for Communicati...  
Full categorised list of videos with PDF Summary Sheets: http://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

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