What is Peak-To-Average Power Ratio? One of the major drawbacks for OFDM devices is the weak performance of an amplifier. There are two primary reasons for this. The first one is due to the usage of QAM modulation. This requires using a linear power amplifier to meet ACLR (Adjacent channel leakage ratio) requirements for performance. This is true in any system employing QAM modulation. Take UMTS as an example however, in OFDM systems, this is further complicated by another factor that is related to the nature of multi-carrier the OFDM signal
