Bluetooth technology

The research addressed and deliberated in this thesis refers to CMOS VLSI design approach of a Bluetooth™ receiver front-end. The performance outcome o f the design is verified with ADS™ RF simulation tool. Essentially the thesis offers an outline on the Bluetooth™ technology and its RF front-end component requirements. The relevant specifications of the
designed front-end blocks are identified and are in concurrence with CMOS technology based
topologies. For each block identified, both circuit parameters and device characteristics are chosen as
per available design formulations and empirical results in open literature. Specifically,
the topology sections designed include antenna input matching, transmit/receive switch,
necessary filters, low noise amplifier, mixer and phase lock loop units. The numerical
TM, (designed) circuit parameters are duly addressed in appropriate ADS simulation tools
and performance evaluations are conducted. Observed results including any deviations
are identified and reported. The thesis concludes with a summary and indicates direction
for future work.

This research work deals with analyzing the performance of a new protocol for distributed network formation and re-formation in Bluetooth ad-hoc networks. The Bluetooth network may be a piconet or a scatternet consisting of a number of piconets. One of the salient features of this protocol is that, there is no leader election process involved. We can establish simultaneous multiple connections between masters and slaves. The delay in formation of the network is analyzed with respect to the number of devices in the network. Also, the network diameter, the number of piconets formed and the impact of device failures are analyzed. Simulation results show that the protocol handles the failures of the devices with minimum delay except at the time of failure of a master. The scope for further improvement of this protocol is also discussed.

This research work deals with analyzing the performance issues of Bluetooth networks such as Piconet and Scatternet. Bluetooth systems with the basic protocol layers such as Bluetooth radio, Baseband, L2CAP, and LMP were simulated to study the performance issues. The primary focus of this simulation study is to observe the effects of packet transmission delay and the number Bluetooth of packets transmitted. The performance characteristics were obtained with varying number of links in a Bluetooth Piconet/Sctternet setup and with variation in information traffic pattern such as Exponential Traffic and FTP traffic patterns. The performance characteristics were obtained with variation in packet types also. The simulation results of the study, are presented in terms of packet transmission delay, number of packets transmitted, comparative study of packets with and without error codes in graphical representations.

Wireless communication has become a significant part of our life. Bluetooth(TM) Radio system is one example of wireless communication, Wireless Local Area Network (WLAN) is another example of wireless technology. Both of systems operate in the same frequency band, the Industrial Scientific Medical (ISM) band, which use a 2.4 GHz carrier frequency. According characteristic of system, multi-path effect are major concern for indoor propagation. A frequency sounding technique is introduced to determine characteristics of the multi-path signal. However, multi-path can not be evaluated directly; some parameters are measured to determine the effect of multi-path. Angles of arrival can be used to facilitate the effect of multi-path signal. Using MatLab programming, Spatial Filter Periodogram (SPF) is introduced to estimate angles of arrival.

This study presents computer simulations directed to address the performance of a baseband Bluetooth system. These simulations help to understand the performance impairments experienced by the Bluetooth systems in the presence of external electromagnetic interference (EMI) and interference that arises from piconet neighbors. The simulation results show that the effect of small scale fading is an important factor that decides the performance of a Bluetooth system. Additionally, it is shown that the interference from piconet neighbors or the interference that stems from devices belonging to the same piconet can be reduced by using frequency-hoping and time synchronization improvised within the same piconets. The test simulations were performed using MatlabRTM and SimulinkRTM tools.

We explored the possible effects of various interferences on Bluetooth devices in the ISM band. We developed a model of Bluetooth and interference from sources such as WLAN devices and Microwave oven, and evaluate the functionality of Bluetooth in the presence of these interferences. As a first step we created Bluetooth, WLAN and Microwave oven models using SPW (Signal Processing Workstation). In our exploration, we undertake three cases: (1) When the Bluetooth is in the presence of only noises in the channel; (2) When the Bluetooth is in the presence of Microwave oven interference; (3) When the Bluetooth is in the presence of WLAN interference. We show that these models can be used to analyze the interferences on the Bluetooth in the ISM band. Future efforts of our group will be to analyze this Bluetooth model with combined interference from all the sources, to come up with possible solutions to reduce the effect of these interferences.

Wireless Personal Area Networks (WPANs) are becoming popular with mobile professionals. Bluetooth is a Wireless Protocol proposed by the Bluetooth SIG (Special Interest Group). Bluetooth allows a user to create a WPAN just by inserting a chip into a mobile device. Such devices are called Bluetooth enabled devices. The market for Bluetooth enabled devices is going to boom in the coming few years. For this reason, it is important to analyze the performance of a Bluetooth network in proximity to other Bluetooth networks. Important issues addressed by such analysis include data security and interference caused by other Bluetooth devices and non-Bluetooth devices. The objective of this research is to evaluate the performance of a Bluetooth network in the presence of interference caused by neighboring Bluetooth networks. This is called mutual interference. The simulation is done with consideration of different packet lengths, where packet lengths are distributed geometrically. The research also considers the near-far effect on the throughput of a Bluetooth unit. The effect of environmental conditions on the performance of Bluetooth Scatternet is also examined.

Wireless personal area networks (WPAN) are becoming more and more popular for use by mobile professionals in areas like airports, hotels, or convention centers. The demand for wireless networks is expected to undergo an explosive growth as Bluetooth(TM) capable devices become more and more popular. In such a scenario, it is imperative that designer are aware of the performance characteristics of several Bluetooth(TM) networks operating within the same area. There are several issues that need consideration like security, self-interference and adjacent network interference. The objective of this research is to evaluate the performance of a Bluetooth(TM) network in the presence of self-interference which included adjacent and co-channel interference from neighboring Bluetooth(TM) networks. Specific to the above topics of interest, the following research tasks are performed: (1) The magnitude of self-interference problem in Bluetooth(TM) networks. (2) The system throughput is evaluated by varying duty cycles of the various networks. (3) The pathloss difference is measured between the desired and the interfering device.

What have been envisaged and focused in the research as deliberated in this dissertation, refer to certain state-of-the-art perspectives of modern wireless telecommunications. Specifically, the objectives and scope of the research efforts carried out include systematic analyses of two major wireless technologies, namely, the Bluetooth(TM) and the CDPD system. The relevant tasks undertaken refer to analytical modeling, experimental studies and simulations pertinent to the performance considerations of the test systems subjected to EMI/RFI influences. The following can be enumerated as the specific research endeavors pursued and completed: (1) Identification of performance implications in the Bluetooth(TM) and CDPD wireless transmissions subjected to EMI/RFI ambients. (2) A comprehensive presentation on the system description, performance requirements, protocol issues and operational environments of the two wireless technologies under study. (3) Development of analytically tractable models, which describe the extent of EMI/RFI on the Bluetooth(TM) operations and provide expressions to compute the transmission impairments involved in terms of the associated packet losses. (4) Modeling of CDPD performance and deducing the statistics of data packets seizing the free AMPS channels. The associated results offer compatible simulations to deduce the data packet blocking probability. The enhancement of such blocking caused by any impulse-like noise invading the system is also modeled. (5) Proposals for methods towards EMI solutions through adopting novel shielding in the wireless systems. The aforesaid efforts are comprehensively addressed supplemented with appropriate background details and literature survey. In conclusion, the scope of the present study is discussed and possible open-questions for future study are identified.