Bluetooth is an open standard which provides communication at short-range between mobile devices which operate in the unlicensed range of 2.4 GHz. With its short range and low power requirements it enables the deployment of personal area networks. The ubiquity of other networking technologies such as IEEE 802.11 Local Area Networks means that wireless, short-range communication technologies such as Bluetooth will have to coexist with these 802.11 networks (Zeadally et al., 2004). Interference in the IEEE 802.11 range is a common problem faced while working with the Bluetooth standard. In the present research, the author would be suggesting ways which could curb or at least lessen the interference in the IEEE 802.11 range. It would improve the performance of the Bluetooth to a significant level.
2. IEEE 802.11 Interference: Background and Motivation
The recent success of wireless technologies has boosted the development of wireless networking. Both industry and academia have turned their attention to this area, attracted the former by intriguing research issues, the latter by market revenues. The goal of the standard is to deliver services previously found only in wired networks, within mobile users with high throughput, high reliability and continuous network connection. For this reason, IEEE802.11 based networks are often referred to as Wireless LANs. The wireless environment poses some challenging problems the network design has to cope with. Firstly, the radio channel is prone to errors and temporary failures which are not encountered in the wired world, secondly, the channel is shared and resources are often scarce. In this scenario, the employed access control schemes are key points for achieving effectiveness.
In the present research, the author would study the ways to curb the interference in the IEEE 802.11 standard.
3. review of previous work
Many solutions to the problems of interference in the IEEE 802.11 standard have been proposed in the past few years when the Bluetooth coexist with it. Non-collaborative resolution deal with power control, MAC scheduling, Adaptive Frequency Hopping, and traffic control (Golmie and Chevrollier, 2001; Golmie, 2003). All these advances use comparable techniques to sense the occurrence of other transmissions in the band by measuring the bit or frame error rate, the signal strength or the signal to interference ratio. For example, the authors carried out analytical and simulation studies, and derived a mathematical model for packet success probability in terms of the Bit Error Ratio (Carlos and Agarwal, 2002). The main difficulty faced by designers and implementers to realize this approach in practice is that they do not have access to the link manager, base band, or radio layers. Thus, it is not likely to apply this solution based on BER since programmers and users do not have access or means to verify BER of channels during Bluetooth transmissions.
In another such attempt, the authors introduced an original architecture BlueStar where selected Bluetooth devices, which are called as Bluetooth Wireless Gateways, are also IEEE 802.11 enabled so that these BWGs could serve as outlet as well as entrance points to and from the IEEE 802.11 network. The authors proposed a hybrid approach of AFH and Bluetooth Carrier Sense of the channels to mitigate interference. With this approach, channels are marked as good or bad based on the value of Packet Error Rate. BCS mandates that before packet transmission, the transmitter senses the channel for activity. The drawback of this approach is that it is a purely hardware based solution and is not likely to be widely deployed due to the obvious reasons and used unless Bluetooth makers and trader implement this scheme in their Bluetooth hardware products thereby limiting the convenience of this approach when used with industrial Bluetooth products. (Carlos et al., 2003)
In their paper, Carlos and Agarwal (2002) proposed an interference-aware Bluetooth segmentation algorithm called IBLUES to cope with interference generated by neighbouring Bluetooth piconets. The basis behind this algorithm is that big packets do better than small packets over low interference as they are associated with low overheads. In contrast, small packets are most suitable for high-error rate channels.
Hence the author believes a study of the interference in the IEEE 802.11 is essential for the desired working on the Bluetooth standard.
4. Aims and Objectives
Following are the aims and objectives of the research project on improving the quality of transmission in the Bluetooth standard by decreasing the interference in the IEEE 802.11 standard.
- Study of the various proposed and experimented techniques to reduce the interference in the IEEE 802.11 standard for the proper working on the Bluetooth devices
- Comparing the various methods and analysing the best technique for reducing the interference
- Suggesting additional techniques which could reduce the interference in the IEEE 802.11 standard.
5. Project Scope
The research project is based on studying the various techniques which could be helpful in reducing the interference in the IEEE 802.11 standard which is used in the Bluetooth transmission. The study would compare the various methods proposed by researchers and analyse these techniques to come up with a hierarchy of the best techniques.
The goal of this research is to study and if possible implement a scheme that enables robust Bluetooth transmissions which is minimally affected by the 802.11 interference traffic. The research would involve the study of the various techniques involved in reducing the interference in the Bluetooth transmission. The researcher would practically test the Bluetooth transmission within the IEEE 802.11 range by carrying out experiments using the various researches which would be studied in detail. After analysing the working of the various techniques in reducing the interference the research would report the finding which is the best technique in reducing the interference in the IEEE 802.11 standard while working with Bluetooth transmission.