Proposal of a Null Subcarrier Allocation Method for CAZAC-OFDM Systems

摘要

A major drawback of Orthogonal Frequency Division Multiplexing (OFDM) signals is the extremely high Peak-to-Average Power Ratio (PAPR). Constant Amplitude Zero Auto Correlation (CAZAC) precoding can dramatically improve the PAPR of OFDM signals, i.e., up to the same PAPR value of single carrier signals with the same modulation scheme. One negative point of the CAZAC precoding technic is not being able to meet the current wireless standards, which usually require a null subcarrier allocated on the center of data subcarriers. In this paper, we demonstrate the CAZAC-OFDM which completely satisfies the 4G-LTE standard by using the proposed allocation method for a null subcarrier without degrading the PAPR and the Bit-Error-Rate.