Fig. 2

Optical spectrum of one unmodulated x-polarized/y-polarized optical carrier and eight orthogonal polarized optical signals. (a) Optical spectrum of one unmodulated x-polarized optical carrier and eight orthogonal polarized optical signals (four x-polarized and four y-polarized optical signals) modulated with 25 Gbps 32-QAM-OFDM signal. (b) Optical spectrum of one unmodulated y-polarized optical carrier and eight orthogonal polarized optical signals (four y-polarized and four x-polarized optical signals) modulated with 25 Gbps 32-QAM-OFDM signal.