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The operation of positioning people and objects has always been important and will be more important in the next years. However, there exist two categories of positioning systems: Outdoor and Indoor.
Global Positioning System (GPS) is well known for outdoor positioning estimation. But because the influence of multi-path or radio disturbance inside buildings it is hard for GPS to supply accurate location information to users (Won et al., 2013). Due to this inconvenient, a lot of methods to achieve indoor positioning are made. Some of these methods are based on infrared or ultrasonic, radio-frequency and Wi-Fi where a large error distance range from centimeters to meters are given (Yang et al., 2012). Elsewhere, in literature (Zhou, Kavehrad, & Deng, 2012) there are mainly three mathematical techniques with their algorithms used in wireless Indoor Positioning Systems (IPS), these principles are: proximity, triangulation and scene analysis. Triangulation is based on the knowledge of geometric properties of triangles to determine the target location. This technique consists of two branches: Lateration and Angulation. Trilateration technique which is used in this paper to determine the target location by measuring its distance from multiple points with known coordinates called reference points (Hassan et al., 2015). With the evolution of the bulbs the Light Emitting Diode (LED) appeared like a best alternative of the traditional lamps due to its ability to deliver a communication signal. The technology which uses LED light in the wireless optical communication is called Visible Light Communication (VLC) (Xu et al., 2016). It is a recent technology to detect targets in indoor environment, where it's very remarkable as a new type of wireless communication technology with less energy consumption and it has many advantages such as: it is free, has large bandwidth, high security and environmentally safe (O’Brien et al., 2008; Jovicic, Li, & Richardson, 2013; Hassan et al., 2015). In addition, the no affected to Electromagnetic Interference (EMI) allows VLC to be applied in many sectors like hospitals, airplane, smart cities, smart homes and offices, etc, where the Radio Frequency (RF) communication is in interference with equipment's signals. Hence, VLC has attracted many interests recently (Komine & Nakagawa, 2004; Afgani et al., 2006; Vucic et al., 2010; Chow et al., 2012). Using VLC in Indoor Positioning Systems (IPS) is a potential energy-efficient and low-cost solution for wireless communication of consumer electronics and improves the accuracy of positioning. Classical receivers used in VLC systems are (PIN) Photo-Diode (PD) or Avalanche Photo-Diode (APD) (Jung et al., 2013; Won et al., 2013; Yang et al., 2012; Zhou, Kavehrad, & Deng, 2012). The drawback of this type of active receivers is the lack of energy efficiency. The advantage of using solar cell is self-powered VLC receiver. Furthermore, VLC-based IPS do not require high speed VLC signals (Zhou, Kavehrad, & Deng, 2012; Jung, Lee, & Park, 2014).
The worldwide solar cell technology is rapidly developed due to the efforts of researchers to increase the efficiency (Fraas & Partain, 2010; Abbott, 2010). Even, solar cells are widely used in many applications like solar phone charges, solar flash light and calculator, etc... (McEvoy, Castaner, & Markvart, 2013; Green, Emery, Hishikawa, Warta, & Dunlop, 2013). As it is-known solar cell is mostly used to harvest solar power (Danesh & Long, 2011; Lee, Kim, & Lee, 2010) but it has also an important role in receiving a wireless optical signal (Wang, Tsonev, Videv, & Haas, 2014).