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Maximizing the Area Spanned by the Optical SNR of the 5G Using Digital Modulators and Filters
        
        High security data link channels having more immunity against channel noise is the need of the century. Free Space 
Optical communication  (FSO)  is  the  modern  technology  which  kick-starts  it’s  application  in  inter  satellite  communication, 
underwater communication and mobile communication to the next level of data transmission by means of complete utilisation 
of the allocated frequency spectrum. In Europe and Asian countries, 5G optical communication will going to expand its usage 
to  nearly  50%  in  upcoming  years  and  so  bandwidth  and  power  efficiency  has  to  be  enhanced  as  much  as  possible  since  the 
consumption  rate  of  the  users  is  increasing  exponentially.  But  increasing  the  distance  increases  the  attenuation  in  case  of 
severe  atmospheric  weather  condition.  In  this  paper,  5G  data  rate  of  50Gbps  is  ensured  for  better  signal  reception  with 
maximum possible link distance between the sender and the receiver keeping variable attenuation environment. The frequency 
of  operation  is  1550nm  throughout  the  processes.  In  this  work,  several  digital  modulation  techniques  and  optical  filters  for 
receiver are  designed and simulated. The  better resulting modulator and filter design in terms of high Quality factor and low 
bit  error  rate  are  considered  and  is  integrated  with  each  other.  The  Signal  to  Noise  Ratio  (SNR)  and  optical  SNR  are 
calculated  for  the  integrated  design  theoretically.  Higher  the  SNR  less  will  be  BER  and  hence  the  signal  connectivity  can  be 
improved in the high speed free space optical communication systems.    
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[23] Yang G., Khalighi M., Bourennane S., and Ghassemlooy Z., “Fading Correlation and Analytical Performance Evaluation of The Space-Diversity Free-Space Optical Communications System,” Journal of Optics, vol. 16, no. 3, pp. 035403, 2014. Guruviah Karpagarajesh is currently working as an Assistant Professor in the Department of Electronics and Communication Engineering at Government College of Engineering, Tirunelveli, Tamil Nadu, India. He has obtained B.E- ECE from P.S.N. ACollege of Engineering and Technology, Dindigul, in the year 2002.He obtained his M.E Optical Communication from ACGCET,Karaikudi, in the year 2005. He has obtained his Ph.D from Anna University, Chennai, in the year June 2017. He has 14 years of experience in the field of Teaching. His areas of interest is Optical Communication. Helen Anita is currently pursuing her M.E., in the Department of Electronics and Communication Engineering at Government College of Engineering, Tirunelveli, Tamil Nadu, India. She received her Bachelor degree in the Department of Electronics and Communication Engineering at Francis Xavier Engineering College ,Tirunelveli in the year 2016. She has published articles in various Journals including IEEE and has presented many papers in National and International Conference. She is a student member in IAENG and life time member in IJARMATE technical platform. Her areas of interest includes Optical Wireless Communication and Communication Networks.
