LTE Spectrum Sharing Research Testbed: Integrated Hardware, Software, Network and Data

This paper presents Virginia Tech's wireless testbed supporting research on long-term evolution (LTE) signaling and radio frequency (RF) spectrum coexistence. LTE is continuously refined and new features released. As the communications contexts for LTE expand, new research problems arise and include operation in harsh RF signaling environments and coexistence with other radios. Our testbed provides an integrated research tool for investigating these and other research problems; it allows analyzing the severity of the problem, designing and rapidly prototyping solutions, and assessing them with standard-compliant equipment and test procedures. The modular testbed integrates general-purpose software-defined radio hardware, LTE-specific test equipment, RF components, free open-source and commercial LTE software, a configurable RF network and recorded radar waveform samples. It supports RF channel emulated and over-the-air radiated modes. The testbed can be remotely accessed and configured. An RF switching network allows for designing many different experiments that can involve a variety of real and virtual radios with support for multiple-input multiple-output (MIMO) antenna operation. We present the testbed, the research it has enabled and some valuable lessons that we learned and that may help designing, developing, and operating future wireless testbeds.Comment: In Proceeding of the 10th ACM International Workshop on Wireless Network Testbeds, Experimental Evaluation & Characterization (WiNTECH), Snowbird, Utah, October 201

Characterization of Indoor Small Cells Propagation

The characterization of the wireless medium in indoor small cell networks is essential to obtain appropriate modeling of the propagation environment. Universal Software Radio Peripherals (USRPs) and simple dipole antennas can emulate LTE-Advanced networks. In this work, we verify WINNER II propagation modeling for the indoor femtocell environment by considering different classrooms of 7.32 x 7.32 square meters near a common University Department corridor while measuring the power received in UEs placed in a grid of 49 points (radiated by the small eNodeB in the centre of the classroom of the own cell). These measurements have been carried out either by using the Software Radio Systems LTE that emulates the LTE-Advanced network and its UEs, or by measuring the received power in the UES with a Rohde & Schwarz FSH8 spectrum analyzer. In room 1, by varying the UE position, the highest values of the received power have occurred close to the central BS, and then in the opposite wall, further away from the interferer. Nevertheless, it was verified that the received power does not decrease suddenly because of the effect of the radiation pattern of the BS and UE antennas for large angles of apertures, as well as due to the non-omnidirectional horizontal antenna pattern. In addition, it was demonstrated that there is an effect of “wall loss” proven by the fact that path loss increases between room 2 and room 1 (or between room 3 and 2). If we consider an attenuation for each wall of circa 7-9 dB the behavior of the WINNER II model at 2.625 GHz for the interference coming across different walls is verified.info:eu-repo/semantics/acceptedVersio

Demonstrating Immersive Media Delivery on 5G Broadcast and Multicast Testing Networks

This work presents eight demonstrators and one showcase developed within the 5G-Xcast project. They experimentally demonstrate and validate key technical enablers for the future of media delivery, associated with multicast and broadcast communication capabilities in 5th Generation (5G). In 5G-Xcast, three existing testbeds: IRT in Munich (Germany), 5GIC in Surrey (UK), and TUAS in Turku (Finland), have been developed into 5G broadcast and multicast testing networks, which enables us to demonstrate our vision of a converged 5G infrastructure with fixed and mobile accesses and terrestrial broadcast, delivering immersive audio-visual media content. Built upon the improved testing networks, the demonstrators and showcase developed in 5G-Xcast show the impact of the technology developed in the project. Our demonstrations predominantly cover use cases belonging to two verticals: Media & Entertainment and Public Warning, which are future 5G scenarios relevant to multicast and broadcast delivery. In this paper, we present the development of these demonstrators, the showcase, and the testbeds. We also provide key findings from the experiments and demonstrations, which not only validate the technical solutions developed in the project, but also illustrate the potential technical impact of these solutions for broadcasters, content providers, operators, and other industries interested in the future immersive media delivery.Comment: 16 pages, 22 figures, IEEE Trans. Broadcastin