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Wireless technology was introduced to replace the cables needed to connect different devices. Traditionally, wireless networks are based on the cellular concept, and have well defined infrastructure support. Since there is frequent use of technology, an on-demand wireless network attracts users by automatically constructing a network. Thus, as of today, many solutions have been proposed for short-range communication but every technology has its own benefits and limitations. Bluetooth (McDermott-Wells, 2004; Morak, Kumpusch, Hayn, Modre-Osprian, & Schreier, 2012) is one of the solutions to connect short-range wireless devices. Technical features of Bluetooth such as non-line-of sight communication, low cost, etc. suit Personal Area Network (PAN) (Chen, Lin, & Chang, 2009). The primary objective of Bluetooth is to replace conventional cables, and connect short-range devices in ad hoc fashion. In the field of communication, Bluetooth use is more encouraging in such areas as connecting headsets, CD players, speakers, medical facilities, sensor networks, etc. Bluetooth can be used to find a location over the internet by capturing the image and verifying it from database. Hence, Bluetooth is a strong candidate for PAN, where devices are connected without cables. Bluetooth devices are connected in an ad hoc fashion in a piconet (S. Tahir, Said, & Bakhsh, 2012), which consists of maximum 8 active slaves as shown in Figure 1.
To develop an indoor position estimation system, mostly three sensing techniques infrared, ultrasound and Radio Frequency (RF) are considered. Infrared signal provides a limited range for communication with direct line of sight transmission. It is an infeasible sensing technology for position estimation in an indoor environment. The frequency of ultrasound signal is very high that needs special hardware and software to measure the ultrasound signal. The frequency of Infrared and ultrasound both are unable to penetrate the physical objects. The RF based sensing technologies are capable to penetrate the physical objects. The range of RF signals can be up to 100 meters (Brett & C. Kwan-Wu, 2011) . The Bluetooth fundamental system consists of a RF transceiver, protocol stack and Baseband (Laharotte et al., 2015). The Bluetooth RF function is internationally accessible with a 2.4 GHz Industrial, Scientific and Medical (ISM) band where hopping covers 79 channels with 1MHz bandwidth. The time interval between different frequencies is 625μs. The Frequency Hopping Spread Spectrum (FHSS) system is used to decrease the interference and increase the security in the Bluetooth network (Roth, Hasler, Goblirsch, & Franczyk, 2015).
Bluetooth devices are centralized, controlled by a master node, which manages slave nodes transmission and allocates slots to active slave nodes. A basic network of Bluetooth is known as piconet and consists of a maximum eight active Bluetooth devices, which includes one master and seven active slaves at a time (de Morais Cordeiro, Abhyankar, & Agrawal, 2004). In reality, Bluetooth is a widely used technology, and capable of much more beyond just connectivity between a small number of devices. Therefore, a Bluetooth network can be extended to multiple piconets, and is called a scatternet. Although Bluetooth specification has defined piconet formations, scatternet formation has still not been standardized.