1. Wireless and Photonic Networks Research Centre of Excellence (WiPNET), Faculty of Engineering Universiti Putra Malaysia, Malaysia
2. Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia (UPM), 43400 Serdang, Malaysia
3. Department of Physics, Faculty of Science, Universiti Putra Malaysia (UPM), 43400 Serdang, Malaysia