Performance of smart antennas with receive diversity in wireless sensor networks

In this paper we propose a Geometrically Based Single Bounce Elliptical Model (GBSBEM) for multipath components involving randomly placed scatterers in the scattering region with sensors deployed on a field. The system model assumes a cluster based wireless sensor network (WSN) which collects information from the sensors, filters and modulates the data and transmit it through a wireless channel to be collected at the receiver. We first develop a GBSBE model and based on this model we develop our channel model. Use of Smart antenna system at the receiver end, which exploits various receive diversity combining techniques like Maximal Ratio Combining (MRC), Equal Gain Combining (EGC), and Selection Combining (SC), adds novelty to this system. The performance of these techniques have been proved through matlab simulations and further ahead based on different number of antenna elements present at the receiver array, we calculate the performance of our system in terms of bit-error-rate (BER). Based on the transmission power we quantify for the energy efficiency of our communication model.

Performance analysis of receive diversity in wireless sensor networks over GBSBE models

Wireless sensor networks have attracted a lot of attention recently. In this paper, we develop a channel model based on the elliptical model for multipath components involving randomly placed scatterers in the scattering region with sensors deployed on a field. We verify that in a sensor network, the use of receive diversity techniques improves the performance of the system. Extensive performance analysis of the system is carried out for both single and multiple antennas with the applied receive diversity techniques. Performance analyses based on variations in receiver height, maximum multipath delay and transmit power have been performed considering different numbers of antenna elements present in the receiver array, Our results show that increasing the number of antenna elements for a wireless sensor network does indeed improve the BER rates that can be obtained.

Antenna selection and channel estimation for hybrid relay systems

The research addressed performance issues for wireless signal transmission and has shown that performance improves with the help of relays due to increased diversity. Further, the areas of antenna selection and channel estimation and modelling has been investigated for improved cost and complexity and has shown to further enhance the performance of the wireless relay systems.

On the multicast lifetime of WANETs with multibeam antennas : Formulation, algorithms, and analysis

We explore the multicast lifetime capacity of energy-limited wireless ad hoc networks using directional multibeam antennas by formulating and solving the corresponding optimization problem. In such networks, each node is equipped with a practical smart antenna array that can be configured to support multiple beams with adjustable orientation and beamwidth. The special case of this optimization problem in networks with single beams have been extensively studied and shown to be NP-hard. In this paper, we provide a globally optimal solution to this problem by developing a general MILP formulation that can apply to various configurable antenna models, many of which are not supported by the existing formulations. In order to study the multicast lifetime capacity of large-scale networks, we also propose an efficient heuristic algorithm with guaranteed theoretical performance. In particular, we provide a sufficient condition to determine if its performance reaches optimum based on the analysis of its approximation ratio. These results are validated by experiments as well. The multicast lifetime capacity is then quantitatively studied by evaluating the proposed exact and heuristic algorithms using simulations. The experimental results also show that using two-beam antennas can exploit most lifetime capacity of the networks for multicast communications. © 2013 IEEE.

Smart cluster bombs - control of multi-agent systems for military applications

This paper introduces an aggregation algorithm for airborne swarming guided weapon systems, which can aggregate munitions into a given shape while reaching the surface. The algorithm uses an artificial force based controller to navigate the members of the swarm into the desired geographical position and evenly distribute them inside the shape. Inter-member repulsion forces are used to avoid collisions among members, which is crucial for a weapon deployment system. Moreover, a lower bound for the release height was obtained which guarantee convergence of the complete weapon system into the target area. The proposed swarming guided weapon system was tested using computer simulations.

RFID-based real-time smart waste management system

In an environmental context, the use of RFID (radio frequency identification) and load cell sensor technology can be employed for not only bringing down waste management costs, but also to facilitate automating and streamlining waste (e.g., garbage, recycling, and green) identification and weight measurement processes for designing smart waste management systems. In this paper, we outline a RFID and sensor model for designing a system in real-time waste management. An application of the architecture is described in the area of RFID and sensor based automatic waste identity, weight, and stolen bins identification system (WIWSBIS).

A proposed smart-card solution for Australian health services : the problems encountered

This case study describes the experience of a state government health department in evaluating the use of smart card technology to redesign health benefits programs for the disabled in Australia. The social and political context of the system is explained in detail, and the potential benefits and risks accruing to the government, health care intermediaries and the community are examined.

The reality of quality systems software : working for the machine, or smart people around the machine?

This case study-based research examines the outcomes of using quality system software (QSS) in terms of the support it provides to, and the constraints it imposes on, its users. The results indicate that QSS can help facilitate knowledge access and sharing, and to a lesser extent, facilitate communication. It can be an effective mechanism for initiating and managing changes to work processes. Although some writers have opined that information technology (IT) is another way of controlling workers, this was not evidenced in this study. Technical shortcomings did hamper performance of some tasks, and for some managers, extra work was involved.

'Don't be a smart arse': Young workers, individualization, and an ethic of enterprise in Jamie's Kitchen

In Jamie’s Kitchen the high profile celebrity chef Jamie Oliver set out to transform a group of unemployed young Londoners into the enterprising, ideal worker of 21st century flexible capitalism. The paper will argue that this reality TV series provides a means to explore key features of new work regimes. We will analyse particular aspects of the increasingly powerful individualising and normalising processes shaping the lifeworlds of young workers in a globalising risk society. Processes that require those who wish to be positively identified as entrepreneurial to do particular sorts of work on themselves; or suffer the consequences.
Drawing on Foucault’s later work on the care of the self, and the  individualization theses of the reflexive modernization literature, we identify and analyse the forms of personhood that various institutions, organisations and individuals seek to encourage in young workers; and the ways in which institutionalised risk environments increasingly individualise the risks and uncertainties associated with labour market participation. The paper argues that our understandings of what it means to be a worker of the world, are being rearticulated around the idea that we are free to choose. And we must exercise this freedom – reap its rewards, carry its obligations – as individuals.

Wireless broadcast encryption based on smart cards

Wireless broadcasting is an efficient way to broadcast data to a large number of users. Some commercial applications of wireless broadcasting, such as satellite pay-TV, desire that only those users who have paid for the service can retrieve broadcast data. This is often achieved by broadcast encryption, which allows a station securely to broadcast data to a dynamically changing set of privileged users through open air. Most existing broadcast encryption schemes can only revoke a pre-specified number of users before system re-setup or require high computation, communication and storage overheads in receivers. In this paper, we propose a new broadcast encryption scheme based on smart cards. In our scheme, smart cards are used to prevent users from leaking secret keys. Additionally, once an illegally cloned smart card is captured, our scheme also allows tracing of the compromised smart card by which illegal smart cards are cloned, and can then revoke all cloned smart cards. The new features of our scheme include minimal computation needs of only a few modular multiplications in the smart card, and the capability to revoke up to any number of users in one revocation. Furthermore, our scheme is secure against both passive and active attacks and has better performance than other schemes.