HIGHLY PRECISE AND FAST COMPUTATION OF THE CONTINUOUS SIGNAL PAR IN OFDM AND DMT SYSTEMS

摘要

Two procedures are developed here to compute the Peak-to-Average envelope power Ratio (PAR) of the continuous signal with N subcarriers in the Orthogonal Frequency Division Multiplexing (OFDM) and Discrete MultiTone (DMT) systems. The first one is an accurate computation method for small N, in which the peak of the Instantaneous Envelope Power Function (IEPF) is obtained by solving the roots of a polynomial, a linear sum of a set of Chebyshev polynomials of the first kind and the second kind. The second procedure, called Stepwise Refinement Algorithm (SRA), is a highly precise and fast computation method for arbitrary N by using Inverse Fast Fourier Transform (IFFT), the Chirp Z-Transform (CZT) and a newly introduced relationship between the IEPF peak and its most adjacent oversampled sample.