A Cost Effective 2 Channel OTDM System Implemented With Sinusoidally Modulated Light Source
We propose to implement a 2 channel optical time division multiplexed (OTDM) system for short reach optical interconnects by using a sinusoidally modulated light source instead of a complicated mode locked laser as an input pulse source. In this system, the OTDM signal is obtained by bit interleaving two optical return to zero (RZ) signals generated by using the sinusoidally modulated light. We operate these RZ signals in the orthogonal in phase and quadrature domains to avoid the unwanted beat components. After the transmission, the OTDM signal is detected by using single photodetector, and then processed by a $2\times 2$ multiple input multiple output equalizer. For a demonstration, we generate 150 Gb/s OTDM signal operating in the 8 level pulse amplitude modulated (PAM 8) format by using commercial LiNbO3 Mach Zehnder modulators and transmit this OTDM signal over 1.9 km of the standard single mode fiber (SSMF) In addition, we fabricate the proposed OTDM transmitter in an integrated silicon photonics chip and use it to demonstrate the transmission of the 64 Gb/s OTDM PAM 4 signal over 2.2 km of SSMF.
IEEE Access