1. Department of Electronics and Communication Engineering, College of Engineering Trivandrum, APJ Abdul Kalam Technological University, Kerala, India;
2. Department of Chemistry, Amrita School of Arts & Sciences, Amrita Vishwa Vidyapeetham, Amritapuri Campus, Kollam, Kerala, India;
3. Department of Electronics and Communication Engineering, Government Engineering College Wayanad, APJ Abdul Kalam Technological University, Kerala, India;
4. Department of Electronics and Communication Engineering, Government Engineering College Kannur, APJ Abdul Kalam Technological University, Kerala, India