“…In this section, the performance of the proposed OAM-OSC system is compared with the different reported OSC systems in terms of data rate, channels, capacity, OSC link length, modulation used, multiplexing employed, and performance, as shown in Table 2 . It is observed that the highest capacity is accomplished in the proposed work as compared to [ 41 , 42 , 44 , 61 , 62 , 63 ]. Moreover, the use of DQPSK [ 41 ], 4-QAM/PSK-OFDM [ 43 ], PDM-QPSK [ 44 ], SP-QAM [ 59 ], PDM-4-QAM [ 37 ], PDM-16-QAM [ 58 ], PDM-64-QAM [ 59 ], and PDM-128-QAM [ 62 ] have been reported in these researches.…”