Analysis of system capacity and spectral efficiency of fixed-grid network

In this article, the performance of a fixed grid network is examined for various modulation formats to estimate the system's capacity and spectral efficiency. The optical In-phase Quadrature Modulator structure is used to build a fixed grid network modulation, and the homodyne detection approach is used for the receiver. Data multiplexing is accomplished using the Polarization Division Multiplexed technology. 100 Gbps, 150 Gbps, and 200 Gbps data rates are transmitted under these circumstances utilizing various modulation formats. Various pre-processing and signal recovery steps are explained by using modern digital signal processing systems. The achieved spectrum efficiencies for PM-QPSK, PM-8 QAM, and PM-16 QAM, respectively, were 2, 3, and 4 bits/s/Hz. Different modulation like PM-QPSK, PM-8-QAM, and PM-16-QAM each has system capacities of 8-9, 12-13.5, and 16-18 Tbps and it reaches transmission distances of 3000, 1300, and 700 kilometers with acceptable Bit Error Rate less than equal to 2*10-3 respectively. Peak optical power for received signal detection and full width at half maximum is noted for the different modulations under a fixed grind network

Single-carrier 72 GBaud 32QAM and 84 GBaud 16QAM transmission using a SiP IQ modulator with joint digital-optical pre-compensation

We establish experimentally the suitability of an all-silicon optical modulator to support future ultra-high-capacity coherent optical transmission links beyond 400 Gb/s. We present single-carrier data transmission from 400 Gb/s to 600 Gb/s using an all-silicon IQ modulator produced with a generic foundry process. The operating point of the silicon photonic transmitter is carefully optimized to find the best efficiency bandwidth trade-off. We present a methodology to split pre-compensation between digital and optical stages. For the 400 Gb/s transmission, we achieved 60 Gbaud dual-polarization (DP)-16QAM, reaching a distance of 1,520 km. Transmission of 500 Gb/s was further tested using 75 Gbaud 16QAM and 60 Gbaud 32QAM, reaching 1,120 km and 480 km, respectively. We finally demonstrated 72 Gbaud DP-32QAM (720 Gb/s) transmitted over 160 km and 84 Gbaud DP-16QAM (672 Gb/s) transmitted over 720 km, meeting the threshold for 20% forward error correction overhead and achieving net rates of 600 Gb/s and 576 Gb/s, respectively. To the best of our knowledge, these are the highest baud-rate coherent transmission results achieved using an all-silicon IQ modulator. We have demonstrated that we can reap the myriad advantages of SiP integration for transmission at extreme bit rates