Performance analysis of multilevel dual polarization OCDMA based modulation using different codes in MDM-OWC system

In this paper, performance investigation of multilevel dual polarization-based modulation is addressed in optical wireless communication system for security enhancement. The proposed system investigates different codes such as DDW code, MD code and ZCCRW code and compares their performance on the basis of distance and receiver pointing error angle. This system uses Optical code division multiple access code to improve security, data rates and minimize multiple access interference. Results revealed that out of the three codes, ZCCRW code shows better performance using multilevel dual polarization modulation followed by DDW and MD code. It provides quality factor of 29 and minimum BER of 10(-160) at the distance of 25000 km. Also, performance has been evaluated on the basis of receiver pointing errors. It is observed that ZCCRW code shows quality factor of 27 and BER of 10(-160) followed by 10 and 8 quality factors of DDW and MD code respectively. The receiver optical power 7 dBm for a distance of 15000 km and as the pointing error increases form 1.1 mu rad to 2.5 mu rad, the ROP ranges from 3 dBm to 1 dBm.