Millimeter-wave Mobile Broadband Research Articles

A New Centralized Access Control Scheme for D2D-Enabled mmWave Networks

In high-density indoor environments (e.g., airports or malls), it is expected an increase in data demand, in the number of applications having stringent Quality-of-Service requirements, and in the number of services among nearby users, such as video sharing or gaming. In order to satisfy these requirements, we adopt D2D communications, 60 GHz band transmissions, and adaptive beamforming techniques. The symbiosis of these technologies provides notable energy saving, high data rate, and strong interference reduction. Despite these benefits, a major issue is the limited communication range, due to the high path loss. To overcome this issue, we consider a Millimeter-Wave Mobile Broadband (MMB) system, consisting of several Access Points interconnected among themselves through a wireless backhaul network. Based on the specific features of the technologies adopted for the considered MMB system, we aim to improve the transmission efficiency, by exploiting concurrent transmissions. Therefore, we propose a new centralized access control scheme which jointly manages D2D communications and transmissions in the access and the backhaul network. Our control strategy aims to maximize the system throughput, to minimize the end-to-end delay, and to improve the fairness among users, while taking into account to keep the computational load as low as possible. To meet these goals, our proposed access control scheme is composed of a data flow management strategy and a multi-criteria scheduling algorithm based on greedy graph vertex-coloring techniques.

A cross-layer design for a software-defined millimeter-wave mobile broadband system

Heterogeneous networks, which deploy small cells in the mmWave band underlying the macrocell network, have attracted intense interest from both academia and industry. Different from the communication systems using lower carrier frequencies, mmWave communications have unique features, such as high propagation loss, directional communications, and sensitivity to blockage. Aiming to overcome the challenging problems in mmWave networks, such as interference management, spatial reuse, anti-blockage, QoS guarantee, and load balancing, we architecturally borrow the ideas of heterogeneous cloud radio access networks and software-defined networking to propose a software-defined mmWave mobile broadband system via a cross-layer design approach. In this architecture, a centralized controller is introduced by abstracting the control functions from the network layer to the physical layer. Through quantitative simulations in a realistic indoor scenario, we demonstrate the performance advantages of our system in terms of network throughput and flow throughput. This work is the first cross-layer and software-defined design for mmWave communications, which opens up an opportunity for mmWave communications to make a significant impact on future 5G networks.

An introduction to millimeter-wave mobile broadband systems

Almost all mobile communication systems today use spectrum in the range of 300 MHz-3 GHz. In this article, we reason why the wireless community should start looking at the 3-300 GHz spectrum for mobile broadband applications. We discuss propagation and device technology challenges associated with this band as well as its unique advantages for mobile communication. We introduce a millimeter-wave mobile broadband (MMB) system as a candidate next generation mobile communication system. We demonstrate the feasibility for MMB to achieve gigabit-per-second data rates at a distance up to 1 km in an urban mobile environment. A few key concepts in MMB network architecture such as the MMB base station grid, MMB interBS backhaul link, and a hybrid MMB + 4G system are described. We also discuss beamforming techniques and the frame structure of the MMB air interface.