Figure 2
From: EVM and achievable data rate analysis of clipped OFDM signals in visible light communication
An example of x(D)[n] , y(D)[n] , x(A)[n] , and y(A)[n] to convey a sequence eight QPSK symbols. For DCO-OFDM, γ = 1.41 = 3 dB, ς = 0.45, c l  = -1.70, c u  = 2.07, B = 1.70; for ACO-OFDM, γ = 0.79 = -2 dB, ς = 0, c l  = 0, c u  = 1.59, B = 0.