Computation of the continuous-time PAR of an OFDM signal with BPSK subcarriers

A procedure for computing the continuous-time peak-to-average power ratio (PAR) of an orthogonal frequency-division multiplexing (OFDM) signal, with binary phase-shift keying (BPSK) subcarriers, is developed. It is shown that the instantaneous envelope power function (EPF) can be transformed into a linear sum of Chebyshev polynomials. Consequently, the roots of the derivative of EPF can be obtained by solving a polynomial. Using the procedure to evaluate the difference between the continuous-time and discrete-time PAR, it is shown that an oversampling factor of four is accurate.