The link misalignment and high susceptibility to blockages are the biggest hurdles in realizing 60-GHz-based wireless local area networks (WLANs). However, much of the previous studies investigating 60 GHz alignment and blockage issues do not provide an accurate quantitative evaluation from the perspective of WLANs. In this article, we present an in-depth quantitative evaluation of commodity IEEE 802.11ad devices by forming a 60-GHz WLAN with two docking stations mimicking as access points (APs). Through extensive experiments, we provide important insights about directional coverage pattern of antennas, communication range, and cochannel interference and blockages. We are able to measure the IEEE 802.11ad link alignment and association overheads in absolute time units. With a very high accuracy (96%-97%), our blockage characterization can differentiate between temporary and permanent blockages caused by humans in the indoor environment, which is a key insight. Utilizing our blockage characterization, we also demonstrate intelligent handoff to alternate APs using consumer-grade IEEE 802.11ad devices. Our blockage-induced handoff experiments provide important insights that would be helpful in integrating millimeter wave-based WLANs into future wireless networks.@en

The rapid proliferation of wireless communication devices and the emergence of a variety of new applications have triggered investigations into next-generation mobile broadband systems, i.e. 5G. Legacy 2G-4G systems covering large areas were envisioned to serve both indoor and outdoor environments. However, in the 5G era, 80 percent of all traffic is expected to be generated indoors. Hence, the current approach of macrocell mobile networks, where there is no differentiation between indoors and outdoors, needs to be reconsidered. We envision 60 GHz mmWave picocell architecture to support highspeed indoor and hotspot communications. We envisage the 5G indoor network as a combination of, and interplay between, 2.4/5 GHz having robust coverage and 60 GHz links offering a high data rate. This requires intelligent coordination and cooperation. We propose a 60 GHz picocellular network architecture, called CogCell, leveraging ubiquitous WiFi. We propose to use 60 GHz for the data plane and 2.4/5GHz for the control plane. The hybrid network architecture considers an opportunistic fall-back to 2.4/5 GHz in case of poor connectivity in the 60 GHz domain. Further, to avoid the frequent re-beamforming in 60 GHz directional links due to mobility, we propose a cognitive module, a sensor- assisted intelligent beam switching procedure, that reduces communication overhead. We believe that the CogCell concept will help future indoor communications and possibly outdoor hotspots, where mobile stations and access points collaborate with each other to improve the user experience@en

Millimeter-wave (mm-wave) communications and nonorthogonal multiple access (NOMA) are two important techniques to achieve high data rates in fifth-generation (5G) ultradense networks (UDNs). Due to interference that is intentionally added during the superpositioned transmissions with NOMA, an additional power budget is required to maintain the target block error rate (BLER). This necessitates the consideration of new approaches to ensure the power efficiency of NOMA systems. In this article, we show that this additional required power can be implemented using the directional transmission capabilities offered by mm-wave antenna arrays. Through the use of our small cells cluster simulations, we investigate the performance of NOMA in mm-wave frequency bands with consideration to the total system capacity, hybrid resource allocation, pairing probability, and power requirements. We demonstrate that a 30° beamwdith, as opposed to a typical 120? beamwidth, can result in a 20% system-capacity gain without requiring any extra transmission power. Our results indicate novel tradeoffs between system capacity, pairing probability, and transmission power in mm-wave NOMA networks owing to the effect of beamwidth variations. We conclude by summarizing the future challenges of NOMA in mm-wave bands.@en

In recent years, enormous growth has been witnessed in the computational and storage capabilities of mobile devices. However, much of this computational and storage capabilities are not always fully used. On the other hand, popularity of mobile edge computing which aims to replace the traditional centralized powerful cloud with multiple edge servers is rapidly growing. In particular, applications having strict latency requirements can be best served by the mobile edge clouds due to a reduced round-trip delay. In this paper we propose a Multi-Path TCP (MPTCP) enabled mobile device cloud (MDC) as a replacement to the existing TCP based or D2D device cloud techniques, as it effectively makes use of the available bandwidth by providing much higher throughput as well as ensures robust wireless connectivity. We investigate the congestion in mobile-device cloud formation resulting mainly due to the message passing for service providing nodes at the time of discovery, service continuity and formation of cloud composition. We propose a user space agent called congestion handler that enable offloading of packets from one sub-flow to the other under link quality constraints. Further, we discuss the benefits of this design and perform preliminary analysis of the system.@en

Ultra-low latency and high reliability communications are the two defining characteristics of tactile Internet (TI). Nevertheless, some TI applications would also require high data-rate transfer of audiovisual information to complement the haptic data. Using millimeter Wave (mmWave) communications is an attractive choice for high data-rate TI applications due to the availability of large bandwidth in the mmWave bands. Moreover, mmWave radio access is also advantageous to attain the air-interface-diversity required for high reliability in TI systems as mmWave signal propagation significantly differs to sub-6 GHz propagation. However, the use of narrow beamwidth in mmWave systems makes them susceptible to link misalignment-induced unreliability and high access latency. In this article, we analyze the tradeoffs between high gain of narrow beamwidth antennas and corresponding susceptibility to misalignment in mmWave links. To alleviate the effects of random antenna misalignment, we propose a beamwidth-adaptation scheme that significantly stabilize the link throughput performance.@en

Millimeter wave (mmWave) communication is being seen as a disruptive technology for 5G era. In particular, 60GHz frequency band has emerged as a promising candidate for multi-Gbps connectivity in indoor and hotspot areas. In terms of network architecture, cloud radio access network (CRAN) has emerged as the most promising architectural alternative to enable efficient baseband processing and dynamic resource allocation in 5G communications. In this article, we propose micro-CRAN (mCRAN) -a multi-gigabit indoor network architecture which leverages availability of high bandwidth in 60GHz frequency band. We have discussed in detail about the requirements and research challenges for various system modules for mCRAN based network architecture. We have also investigated the feasibility of IEEE 802.11ad MAC protocol for the proposed mCRAN architecture. We discuss the challenges related to 60GHz beamforming, medium access mechanisms and network architecture, and propose solutions to address them.@en

Communication at mmWave frequencies has been the focus in the recent years. In this paper, we discuss standardization efforts in 60 GHz short range communication and the progress therein. We compare the available standards in terms of network architecture, medium access control mechanisms, physical layer techniques and several other features. Comparative analysis indicates that IEEE 802.11ad is likely to lead the short-range indoor communication at 60 GHz. We bring to the fore resolved and unresolved issues pertaining to robust WLAN connectivity at 60 GHz. Further, we discuss the role of mmWave bands in 5G communication scenarios and highlight the further efforts required in terms of research and standardization.@en

The 60 GHz frequency band promises very high data rates - in the order of Gb/s - due to the availability of high bandwidth. However, high free-space path loss makes it necessary to employ beamforming capable directional antennas. When beamforming is used, the links are sensitive to misalignment in antenna directionality because of movement of devices. To identify and circumvent the misalignments, we propose to use the motion sensors (i.e., accelerometer and gyroscope) which are already present in most of the modern mobile devices. By finding the extent of misaligned beams, corrective actions are carried out to reconfigure the antennas. Motion sensors on mobile devices provide means to estimate the extent of misalignments. We collected real data from motion sensors and steer the beams appropriately. The results from our study show that the sensors are capable of detecting the cause of errors as translational or rotational movements. Furthermore it is also shown that the sensor data can be used to predict the next location of the user. This can be used to reconfigure the directional antenna to switch the antenna beam directions and hence avoid frequent link disruptions. This decreases the number of beam searches thus lowering the MAC overhead.@en

Recently, the edge resource provisioning schemes were defined considering the low-latency Mobile Edge Computing (MEC) paradigm. Most of these models only consider batterypowered devices like smart-phones, thus are agnostic to the energy harvesting techniques that achieves a green MEC system. Further, most of the studies on MEC assume unlimited edge resources which is not the case as it is with the conventional data-centers (public clouds). Hence, unrestricted use of edge resources is not ideal. This work mainly considers two problems: (1) the offloading of data traffic from the Internet of Things (IoT) devices that rely on energy harvesting to the MEC entities and (2) assignment of the resources at the MEC. The novelty of this paper lies in the energy scavenging based architecture that is developed over the Contiki OS. Secondly, saving the energy for computations to maximize the lifetime of the sensing nodes by performing the execution of the computationallyintensive tasks at the edge which is a single hop away. The proposed architecture uses the ambient triggers to form the sensor network and establish links with computationally capable resources located at the edge. Further, a mathematical model to manage the resources at the edge is proposed. Finally, we evaluate a threshold-policy for optimizing the resources participating in an edge computation service for an IoT scenario and discuss the improvements achieved.@en

The IEEE 'Tactile Internet' (TI) Standards working group (WG), designated the numbering IEEE 1918.1, undertakes pioneering work on the development of standards for the TI. This paper describes the WG, its intentions, and its developing baseline standard and the associated reasoning behind that and touches on a further standard already initiated under its scope: IEEE 1918.1.1 on 'Haptic Codecs for the TI.' IEEE 1918.1 and its baseline standard aim to set the framework and act as the foundations for the TI, thereby also serving as a basis for further standards developed on TI within the WG. This paper discusses the aspects of the framework such as its created TI architecture, including the elements, functions, interfaces, and other considerations therein, as well as the novel aspects and differentiating factors compared with, e.g., 5G Ultra-Reliable Low-Latency Communication, where it is noted that the TI will likely operate as an overlay on other networks or combinations of networks. Key foundations of the WG and its baseline standard are also highlighted, including the intended use cases and associated requirements that the standard must serve, and the TI's fundamental definition and assumptions as understood by the WG, among other aspects.@en