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Massive Multiple Input Multiple Output (MIMO) is an essential component for future wireless cellular networks. One of its biggest advantages is to use the 5G spectrum more intelligently by extending both coverage (via high gain adaptive beamforming) and capacity (via high order spatial multiplexing). In this paper, we evaluate the performance of Time-division duplex (TDD)-based massive MIMO deployment scenario in one of the commercial sites in Turkey. Our experimental results reveal three major contributions: (i) TDD-based massive MIMO in 10 Mhz reveals up to 212% and 50% higher cell throughput compared to Frequency-division duplex (FDD)-based MIMO deployments with 10 Mhz and 20 Mhz respectively. The Downlink (DL) throughput is also observed to be better in mid/far points. (ii) Together with the usage of TDD-based massive MIMO inside the same commercial site, median values of total cell traffic, Uplink (UL) Spectral Efficiency (SE) and DL schedule Transmission Time Interval (TTI) duty cycle have improved 38%, 9% and 14.5% compared to FDD-based MIMO scenario respectively. (iii) Finally, we address some of the challenges of the massive MIMO deployments and the possible trade-offs that can be observed in terms of Radio Resource Control (RRC)-connected User Equipments (UEs), cell throughput, available Sounding Reference Signal (SRS) resources and pairing opportunities provided by massive MIMO.

Enhancing the coverage and eliminating the poor performance is key to balance end-user experience and future network investments for mobile network operators (MNOs). Although vast amounts of infrastructure investments are provided by MNOs, there are still coverage and capacity planning problems at remote locations. This is because, in most cases, the population density and return-of-investments are low in those areas. In this paper, radio access network (RAN) sharing paradigm is utilized on experimental sites in Turkey to accommodate user equipment of multiple network operators under the same cell sites. We first investigate characteristics, benefits, and limitations of two different RAN sharing deployment scenarios. Then, a city-wide experimental RAN sharing study is conducted on live long-term evolution (LTE) networks between two MNOs in Turkey. Through experimental tests, we show overall performance gains of enabling RAN sharing feature in terms of observing various key performance indicators that are obtained from shared base stations. Our experimental results demonstrate that both downlink and uplink average user throughput values increased by 17.8% and 42.85%, respectively. After RAN sharing was enabled between MNOs, increase in the number of user equipment due to higher 4G coverage yielded a higher number of interradio access technology (inter-RAT) handover attempts. This caused inter-RAT handover out success rate to decrease by 70.66%. Intrafrequency handover out success rate, which indicates if the subscriber is using the same RAT type, increased by 358.33% and service drop rates dropped by 86.1%, respectively, after RAN sharing was enabled. Finally, we discuss and summarize the main takeaways of the outcome of the considered large-scale RAN sharing experiments. [ABSTRACT FROM AUTHOR]

The increased demand for Unmanned Aerial Vehicles (UAV) has also led to higher demand for realistic and efficient UAV testing environments. The current use of simulated environments has been shown to be a relatively inexpensive, safe, and repeatable way to evaluate UAVs before real-world use. However, the use of generic environments and manually-created custom scenarios leaves more to be desired. In this paper, we propose a new testbed that utilizes machine learning algorithms to procedurally generate, scale, and place 3D models to create a realistic environment. These environments are additionally based on satellite images, thus providing users with a more robust example of real-world UAV deployment. Although certain graphical improvements could be made, this paper serves as a proof of concept for an novel autonomous and relatively-large scale environment generator. Such a testbed could allow for preliminary operational planning and testing worldwide, without the need for on-site evaluation or data collection in the future. [ABSTRACT FROM AUTHOR]

Unified convergent networks (for fixed and mobile services) are considered to be an important step towards diversifying the set of services operators can provide for their end-users. Although there has been a huge interest to unified convergent networks among mobile network operators (MNOs) and fixed network operators, the convergence is rather slow due to different factors such as regulation, security, policies, spectrum and competitors. Moreover, each operators have different long term strategies and position themselves based on these policies in unified convergent networks. In this paper, we investigate unified fixed and mobile deployment strategy as a unified service, which is different than typical leased line approach that is frequently utilized with no unification or (convergence). We present different QoS strategies of MNOs before and after unified convergent networks and introduce characteristics, benefits and limitations of these strategies. For validation purposes of various QoS strategies, we build a real-world experimental testbed in an operator environment. Our experimental results reveal how emerging services (broadband Internet, voice, cellular) are affected in the studied QoS policies during congestion inside the unified convergent networks architecture for different MNOs. [ABSTRACT FROM AUTHOR]