Performance Evaluation of Free Space Optical Links with NRZ and RZ Line Codes Using APD and PIN Receivers under Diverse Weather Conditions

Jayprakash Vijay, Amit Rathi

Free Space optics (FSO), photo diode, pointing error.

In this paper, we evaluate the performance of a free space optics (FSO) link operating at a wavelength of 1550 nm using non-return-to-zero (NRZ) and return-to-zero (RZ) line codes, as well as avalanche photodiode (APD) and positive-intrinsic-negative (PIN) receivers, under various weather conditions. The study analyzes pointing error and received signal attenuation across different scenarios, including clear air, haze, and fog. Results indicate that the pointing error for NRZ-APD is 11.62 μrad, slightly higher than the 11.22 μrad observed for RZ-APD. However, RZ-APD experienced greater signal attenuation across all weather conditions compared to NRZ-APD. For PIN receivers, the study shows maximum pointing errors of 10.55 μrad and 10.42 μrad for NRZ-PIN and RZ-PIN configurations, respectively, in foggy conditions. These findings suggest that a wavelength of 1550 nm offers optimal performance for FSO links across all weather conditions, with NRZ-APD and RZ-PIN showing advantages in terms of pointing accuracy. This paper provides valuable insights for the design and implementation of robust and efficient FSO communication systems in diverse atmospheric environments.

Received: 14 Oct 2023, Receive in revised form: 08 Nov 2023, Accepted: 18 Nov 2023, Available online: 30 Nov 2023

10.22161/ijaers.1011.11