Praise for the Third Edition: "This is one of the best books available. Its excellent organizational structure allows quick reference to specific models and its clear presentation . . . solidifies the understanding of the concepts being presented."IIE Transactions on Operations EngineeringThoroughly revised and expanded to reflect the latest developments in the field, Fundamentals of Queueing Theory, Fourth Edition continues to present the basic statistical principles that are necessary to analyze the probabilistic nature of queues. Rather than presenting a narrow focus on the subject, this update illustrates the wide-reaching, fundamental concepts in queueing theory and its applications to diverse areas such as computer science, engineering, business, and operations research.This update takes a numerical approach to understanding and making probable estimations relating to queues, with a comprehensive outline of simple and more advanced queueing models. Newly featured topics of the Fourth Edition include:Retrial queuesApproximations for queueing networksNumerical inversion of transformsDetermining the appropriate number of servers to balance quality and cost of serviceEach chapter provides a self-contained presentation of key concepts and formulae, allowing readers to work with each section independently, while a summary table at the end of the book outlines the types of queues that have been discussed and their results. In addition, two new appendices have been added, discussing transforms and generating functions as well as the fundamentals of differential and difference equations. New examples are now included along with problems that incorporate QtsPlus software, which is freely available via the book's related Web site.With its accessible style and wealth of real-world examples, Fundamentals of Queueing Theory, Fourth Edition is an ideal book for courses on queueing theory at the upper-undergraduate and graduate levels. It is also a valuable resource for researchers and practitioners who analyze congestion in the fields of telecommunications, transportation, aviation, and management science.

Fundamentals of Queueing Theory

In the near future, i.e., beyond 4G, some of the prime objectives or demands that need to be addressed are increased capacity, improved data rate, decreased latency, and better quality of service. To meet these demands, drastic improvements need to be made in cellular network architecture. This paper presents the results of a detailed survey on the fifth generation (5G) cellular network architecture and some of the key emerging technologies that are helpful in improving the architecture and meeting the demands of users. In this detailed survey, the prime focus is on the 5G cellular network architecture, massive multiple input multiple output technology, and device-to-device communication (D2D). Along with this, some of the emerging technologies that are addressed in this paper include interference management, spectrum sharing with cognitive radio, ultra-dense networks, multi-radio access technology association, full duplex radios, millimeter wave solutions for 5G cellular networks, and cloud technologies for 5G radio access networks and software defined networks. In this paper, a general probable 5G cellular network architecture is proposed, which shows that D2D, small cell access points, network cloud, and the Internet of Things can be a part of 5G cellular network architecture. A detailed survey is included regarding current research projects being conducted in different countries by research groups and institutions that are working on 5G technologies.

A Survey of 5G Network: Architecture and Emerging Technologies

System Identification I

Despite of several years of innovative research, indoor localization is still not mainstream. Existing techniques either employ cumbersome fingerprinting, or rely upon the deployment of additional infrastructure. Towards a solution that is easier to adopt, we propose CUPID, which is free from these restrictions, yet is comparable in accuracy. While existing WiFi based solutions are highly susceptible to indoor multipath, CUPID utilizes physical layer (PHY) information to extract the signal strength and the angle of only the direct path, successfully avoiding the effect of multipath reflections. Our main observation is that natural human mobility, when combined with PHY layer information, can help in accurately estimating the angle and distance of a mobile device from an wireless access point (AP). Real-world indoor experiments using off-the-shelf wireless chipsets confirm the feasibility of CUPID. In addition, while previous approaches rely on multiple APs, CUPID is able to localize a device when only a single AP is present. When a few more APs are available, CUPID can improve the median localization error to 2.7m, which is comparable to schemes that rely on expensive fingerprinting or additional infrastructure.

Avoiding multipath to revive inbuilding WiFi localization

This chapter contains sections titled: Product Definition for Broadband Wireless Systems Technology Drivers Evolving Wireless Broadband Market Segments Open Systems and Intelligence at the Edge Radio Network System Engineering References

Always Best Connected

There is provided a method comprising: causing a station capable of communication in a wireless network to acquire knowledge of a medium usage indicator with respect to at least one channel applicable for transmission of a scanning request; and determining a transmission time for a next scanning request at least partly based on the medium usage indicator.

Efficiency in Wireless Network

Cooperative radio resource management framework for future IP-based multiple radio access technologies environment

Future wireless networks will enjoy ubiquitous connectivity by taking advantage of the IP core convergence which is seen as the lingua franca of heterogeneous access networks ecosystem. It is expected that the prevalence of WLAN and the advent of IEEE 802.11n standard will continue to offer compelling opportunities and therefore be considered as one of the de-facto wireless access network. However, it is known that wireless network conditions in general are diverse owing to both traffic and wireless channel variations. This raises the importance of exploiting diversity across a multiple access points (multi-AP) WLAN, which requires an advanced network control mechanism to effectuate uniform load distribution, so that QoS of users and composite capacity can be improved. Although various load distribution algorithms for WLAN have been investigated in literature, there is a lack of performance comparison between different algorithms. In this paper, we present a comparison of three dynamic load distribution algorithms, viz. predictive load balancing (PLB), predictive QoS balancing (PQB) and reactive QoS balancing (RQB) for infrastructure-based WLAN with DCF access mechanism based on OPNET simulations.

/pdf/on-dynamic-load-distribution-algorithms-for-multi-ap-wlan-3pnm015h8a.pdf

On Dynamic Load Distribution Algorithms for Multi-AP WLAN under Diverse Conditions

A method, apparatus, and computer program is presented for scanning in a wireless network. A wireless device receives a downlink frame from two access points, the downlink frames indicating their respective transmission powers. The wireless device then determines the closest access point and a transmission power sufficient to reach that access point. Then, the wireless device carries out transmission of a probe request with the determined transmission power.

Improved scanning in wireless network

With the emerging IEEE 802.11n standard, the WLAN is poised as a promising ubiquitous networking technology to support multimedia applications where providing QoS becomes imperative. However, the 802.11 WLAN is not designed to support delay sensitive traffic. This problem is magnified during a handover and typically results in excessive handover latency and packet loss. In addition, a 802.11 WLAN handover process is predominantly based on the physical layer detection without QoS considerations. This often causes overloading of access points and consequently all its associated connections would suffer from high delay. The former can be resolved by reducing handover latency to achieve seamless handover and the latter can be mitigated by employing link layer detection in the 802.11 WLAN handover process and having an appropriate admission control scheme. Although the IEEE 802.11e standard supports prioritized QoS, it cannot guarantee strict QoS required by real-time services under heavy load. In this paper, we proposed an integrated load balancing scheme incorporating (i) QoS-based fast handover to support seamless handover by eliminating both detection and scanning phases from the 802.11 WLAN handover process; and (ii) soft admission control to protect QoS of existing connections when resources are low. This synergy allows us to perform QoS-related handover opportunistically and guarantees service QoS during and after handover respectively. Simulations showed that our proposed integrated load balancing scheme is capable of providing seamless handover and QoS provisioning for real-time VoIP services in terms of bounded delay and packet loss when considering multimedia traffic. Particularly, our proposed scheme exhibits both throughput and QoS fairness which jointly optimize overall system utilization.

/pdf/an-integrated-load-balancing-scheme-for-future-wireless-52bl715gdy.pdf

Eng Hwee Ong

Papers

Efficiency in Wireless Network

Cooperative radio resource management framework for future IP-based multiple radio access technologies environment

On Dynamic Load Distribution Algorithms for Multi-AP WLAN under Diverse Conditions

Improved scanning in wireless network

An Integrated Load Balancing Scheme for Future Wireless Networks