Manvi Sahni and Sumanta K. Das
Efficient risk analysis and threat management are essential requirements of modern air defense (AD) systems. The paper is a half-way between the analytic hierarchy process (AHP) and the practical reasoning to model and analyze the risk and threat related to military AD applications. The models are applied for decision making tasks of AD command and control (C2) for assessing and prioritizing the threat from hostile targets for efficient risk management. The paper presents a method for threat assessment using the fuzzy set theory, the AHP and the technique for order preference by similarity to ideal solution (TOPSIS). The target’s threat attributes are first represented using the fuzzy set theory. The subjective opinions of the experts about different alternatives are quantified and ranked following the solutions of the AHP process. These solutions of AHP are obtained through the TOPSIS for prioritization. The models are implemented in a simulated environment. The simulated system runs without any human intervention, and represents the state-of-the-art model for the C2 system. The use of the fuzzy set theory, AHP and TOPSIS for decision making task is particularly useful from the point of view of the futuristic risk and threat management in the battlefield. This method is easy to implement in practice and good at real-time application.
Keywords- Analytic Hierarchy Process (AHP), Multiple Attribute Decision Making (MADM), TOPSIS, Threat Assessment, Air Defense.
D. Vijay Rao, Manpreet S. Karri and Monalisa Sarma
With rapid advances in technology, there is an ever increasing need for deploying increasingly complex defence systems to be fielded in operation within costs, time and acceptable end-use functionality. The design of such large-scale military systems are done by integrating off-the-shelf sub-systems, and component-based systems along with indigenously developed systems, ensuring interoperability, functionality and performance. As the size and complexity of systems increases, the design problem goes beyond component and subsystem design or the design of algorithms and data structures of the computation in the sub-systems. The proliferation of software systems have triggered a transition from the hardware oriented military systems to systems that are controlled by software and more so towards embedded systems. In this paper, we extend and apply a framework based reliability assessment approach for a naval system architecture based on a scenario analysis. This approach enables us to infer the system reliability from aspect reliabilities based on the composition methods, allowing the application specific aspects to be added dynamically or upgraded at a later stage. The design of a system as a framework that can support plug-in application specific aspects is an effective way of simplifying the system and assuring high quality by making the specification of each aspect as well as composition component more amenable to rigorous analysis. In order to assess the performance of these systems in various real time warfare scenarios, a Discrete Time Markov Chain is constructed. This methodology can be applied in early design stages to allow the designer to understand the effect of operational degradation factors and their effects that occur over the days of war. The methodology has been effectively applied to carry out the sensitivity analysis of the sub-systems with respect to the scenario based operations and compute mission reliability.
Keywords—Reliability Assessment; Architecture based Reliability; Performance Evaluation; Mission Reliability.
Kurt Brown
The battlespace is a complex environment comprising of multiple domains, maritime, air, land and cyber, across a diverse range of scenarios. These scenarios span conventional warfighting to humanitarian assistance, requiring complex processes and systems and demand the enabling of increasingly technologically advanced platforms. To generate a battlespace effect information must traverse efficiently and effectively linking these diverse platforms spread between domains and across the breadth of scenarios. Currently, within the land domain this information is pushed by the Enhanced Position Location Reporting System (EPLRS) data network. However, this network will be challenged to meet emerging platforms, requirements which demand big data such as the: Joint Strike Fighter, next generation Unmanned Aerial Vehicles, P8, and increasingly complex processes such as deliberate and dynamic targeting using Full Motion Video. To enable complex processes and emerging platforms a scalable and flexible data network is required providing beyond line-of-sight, single hop connectivity to enable time critical applications and high bandwidth, big data. This paper proposes that a cellular, Fourth Generation (4G) Long Term Evolution Advanced (LTE+) architecture can meet these demands now and into the future providing a revolutionary military communications capability to the Australian Defence Force, specifically the Army.
Keywords—tactical communications, battlefield communications, cellular communications.
Kusumkant D. Dhote, Krothapalli P.S. Murthy, Kizhakkel M. Rajan and Mahesh M. Sucheendran
This paper reports on studies into the effect of casing material on the fragment spatial distribution of a Fragment Generator Warhead (FGW). Usually, metals are used for the manufacture of the warhead casing which is manufactured using conventional methods. Recently, FGWs have been designed with complex contours to meet the specific requirements of interceptor missiles. Manufacturing of such casings using conventional methods has been observed to be difficult and time consuming. Alternatively, the casings can be manufactured with ease by rapid prototyping (RP) methods using non-metallic materials. In order to study the effect of metallic and non-metallic materials, the authors conducted a comparative performance analysis of aluminium and Dura Form Glass Filled (DFGF) warheads manufactured by conventional and RP methods, respectively. The warheads are designed to yield a fragment beam of 32° in azimuth and 20° in elevation. The experimental details are presented and it is concluded that uniform fragment spray is only yielded from the metallic casings manufactured by conventional methods.
Keywords—fragment generator warhead, interceptor missiles.
Arthur Ollett and John Coleman
Adopting an open systems approach (OSA) during the requirements definition phase of Australian Defence Force (ADF) procurement programs will help break the stove-pipe stranglehold on communication and information system capability. The resulting return on investment will be the delivery of a set of agile capability solutions that are easily enhanced to meet future requirements while at the same time reducing vendor lock-in, risk and support costs. A snapshot of ADF projects are reviewed and we discuss potential strangulation issues regarding ambiguous boundaries and associated risks that could be addressed by an OSA. A brief overview is provided on the OSA initiatives underway by other country’s defence agencies including; UK MOD, US DoD and NATO. We introduce a high level platform concept that could be used as a framework when defining project requirements with an OSA discuss the short and long term benefits that could be achieved. We conclude that an OSA is a future-proofing acquisition strategy that can yield important benefits such as capability gain, more open competition, ability to re-use rather than replace, ultimately reducing waste and lowering costs.
Keywords—open systems approach, communication systems, information systems.
Ajit Reddy
In this paper we discuss the architecture and the implementation of 5 Mbps over-the-air data rate, burst mode data link which has the capabilities of the upstream and downstream transmission in a single module with symmetrical data rates in time division duplex (TDD) manner. The data link operates in the S band. In this paper, we discuss the various RF challenges that exist on a RF system-level and show how such challenges can translate into implementable circuit designs. The reason for a TDD-based RF front end is that TDD is known to offer cost advantages as compared to FDD-based system. The additional advantage is that it uses less space compared to FDD and where size is an issue. The fundamental subsystem blocks such as synthesizers, filters and power amplifiers are where most of the RF front end transceiver costs reside. We also discuss some of the important modem specifications for RF and baseband and the implications for the design of RF circuits, which include SNR, channel bandwidths, RF bands, noise figures, output power levels, and gain setting.
Keywords—data link, burst mode transmission.
Benjamin L Hoggan, Michael G Lenné, Justin T Fidock and Eugene Aidman
The Australian Army is procuring field vehicles incorporating new in-vehicle information technologies to increase their logistics support capacities in high-risk areas. These technologies will require multi-person crews to replace single driver-operators. As part of a research program exploring the impact of performance-shaping factors on vehicle crews, 16 soldiers operated simulated vehicles in driver/co-driver pairs, under different levels of task demand and over extended time periods. Participants performed a primary task related to their crew role, along with a concurrent auditory secondary task which was varied in complexity and incorporated a dyadic within-crew communication component. Co-drivers, whose primary task was a continuous N-back visual working memory task, experienced significant performance declines with time-on-task across all tasks, with greater deterioration when secondary task complexity was lowest. Drivers, whose primary task was maintaining consistent speed and lane position, showed relatively stable performance across tasks, regardless of secondary task complexity. The results provide support for effort regulation theory, with potential under-mobilisation of effort and resources to compensate for underload effects (such as loss of task-related engagement) induced by monotonous, undemanding conditions. Potential strategies to counter such conditions in field vehicles (e.g., secondary tasks, in-vehicle systems), study limitations, and directions for planned research are discussed.
Keywords—data link, burst mode transmission.
