Water-Filling Random Resource Allocation (W-FRRA) Using NOMA for Downlink LiFi System

In this paper, we proposed random resource allocation using water filling for Light Fidelity (LiFi) system, namely Water-Filling Random Resource Allocation (W-FRRA). This paper assumes that the room has several things that can be reflected or absorbed the light from LED bulb and produce blocking probability. We consider that users always move and change, randomly in a room. We use 4x4x3 m for room dimension and power bias 1 W to transmit power for the first time. Power control is used to organise signal to noise ratio (SNR) for equality data rates in any user locations. Our simulation shows that after employee W-FRRA, all of users has similarity data rates around 90Mbps for any propagations distance. After equality data rates are achieved using power allocation, we concentrate for limited time-slot resource, unpredictable packet edge and consider to using Non-Orthogonal Multiple Access (NOMA) for increasing the throughput of LiFi. To prove that our proposed method has improve, we compare random packets transmission such as Slotted ALOHA (SA) and Contention resolution diversity slotted ALOHA (CRDSA). We validate the results using packet loss rate and throughput performances based on computer simulation. We found that W-FRRA has highest performance among SA and CRDSA with most number of user can be served. In addition, the throughput performance of W-FRRA has higher around 10% and 30% than CRDSA and SA, respectively. We also prove that our proposed has fairness system and already employee NOMA to serve users without collision for every location on LiFi system.