Performance comparison of implementing ASK and PPM modulations for free space optics system integrated with FBG device

Free Space Optical Communication (FSO) has evolved as an achievable technology with high bandwidth and data rate besides a low Bit Error Rate (BER). The FSO system has recently replaced fiber optic cabling and radio frequency communications. Therefore, FSO system employees have free space to send data carried via light with a high data rate over a long distance. A comparative study is conducted between Amplitude Shift Keying (ASK) and Pulse Position Modulation (PPM) techniques for FSO channels with the usage of Fiber Bragg Grating (FBG). The developed design of FSO systems for ASK and PPM modulation techniques is carried out via the Optisystem 7 and 18.0 software simulators. In the presence of high attenuation of 34 dB/Km and at 1552 nm wavelength, the performance of the Number (N-FSO) channels with FBG provides perfect, effective and efficient optical communications in terms of high Q-factor and low BER up to 5000 m link distance. Moreover, the developed design of the FSO channel with the implementation of FBG shows a high Q-factor and low BER for ASK and PPM configurations compared to the FSO channel without FBG. However, the N-FSO system using the ASK modulation scheme with FBG provides a maximum Q-factor of 3306 with a minimum BER of 0. Furthermore, the results show that the developed design of N-FSO using the ASK modulation technique offers better performance than the PPM technique.