• Tuesday, 13 June, 11:30-13:00, Room Theatre Big Stage
  • Session Chair: Kari Leppanen (Huawei Technologies, Finland)



11:30  - Antenna Configuration Comparison in Challenging NLOS Locations

Juha Erkkilä and Marjut Koskela (Centria University of Applied Sciences, Finland); Joni Heikkilä (Central Ostrobothnia University of Applied Sciences, Finland); Tuomo Kupiainen, Marjo Heikkilä and Tero Kippola (Centria University of Applied Sciences, Finland); Asko Nykänen and Risto Saukkonen (Nokia Mobile Networks, Finland)

The objective of this paper is to compare uplink (UL) performance with different antenna technologies when receiving Non-Line of Sight (NLOS) signal in field tests. The antenna configurations in use were a passive antenna system and an active antenna system (AAS). The radiation pattern can be controlled horizontally by changing its azimuth angle and vertically by changing the tilt angle of the antenna. AAS includes a flexible configuration that consists of diversity beams and other features for beam controlling. The field trial benefitted 2-way and 4-way receive (RX) diversity in both antenna systems. The field trial environment consists of three macro-cellular Long Term Evolution (LTE) evolved Node B (eNB) operating in 2.1 GHz band. This trial environment has two AAS and one passive system in use for the measurements. The environment can encompass one macro cell and with vertical controlling, it is possible to add an additional beam and with horizontal controlling it is possible to steer the main beam towards the user equipment (UE). Field trial used drive test software to evaluate the test network performance. Mobile network user had UE in drive testing to evaluate cellular network quality from the mobile device's point of view. The field trial results indicate that AAS beam controlling can achieve remarkable capacity gain in uplink direction when UE does not have a line of sight to the eNB.


11:48 - A Channel Allocation Algorithm for Citizens Broadband Radio Service/Spectrum Access System

Kapuruhamy Badalge Shashika Manosha (Centre for Wireless Communications, Department of Communications Engineering, University of Oulu, Finland); Satya Krishna Joshi and Tuomo Hänninen (University of Oulu, Finland); Markku Jokinen (University of Oulu & Centre for Wireless Communications, Finland); Pekka Pirinen (University of Oulu, Finland); Harri Posti (Centre for Wireless Communications, Finland); Kari Horneman (Nokia & Bell Labs, Finland); Seppo Yrjölä (Nokia Innovation Steering, Finland); Matti Latva-aho (UoOulu, Finland)

Recently, the Federal Communications Commission has proposed to create Citizens Broadband Radio Service (CBRS) with the three-tier spectrum sharing system to release more spectrum for the mobile broadband usage in the United States. At the moment, the Wireless Innovation Forum is involved in defining the operational and functional requirements for this framework based on [1], and also in standardizations. Evidently, the successful operation of this system depends on efficient channel allocation algorithms. In this paper, we consider the CBRS with the three-tier spectrum sharing system. A set of CBRS users, i.e., Priority Access License (PAL) and General Authorized Access (GAA) users are located in an area, which is divided into multiple census tracts. The PAL and GAA users request frequency channels from the spectrum access system (SAS). The role of the SAS is to allocate channels to these two types of users while providing interference protection to the incumbent users. For this setup, we consider the problem of channel allocation for PAL and GAA users. The objective is to allocate channels for these two types of users, while considering the channel allocation rules proposed in [1]. For this problem, we propose a channel allocation algorithm to be used by the SAS. The proposed algorithm allocates channels to the CBRS users in two steps: 1) allocate channels to the PAL users and 2) allocate channel to the GAA users. Numerically, we show that the proposed algorithm is able to allocate channels while satisfying the rules proposed in [1]. More importantly, this research provides new insights on investigating channel allocation algorithms in CBRS/SAS.


12:06 - Link Performance Evaluation for mmWave Systems

Vaia Kalokidou and Mark Beach (University of Bristol, United Kingdom (Great Britain)); Peter J Legg (Blu Wireless Technology, United Kingdom (Great Britain)); Timothy Pelham (University of Bristol, United Kingdom (Great Britain)); Andy Lunness (Blu Wireless Technology, United Kingdom (Great Britain))

This paper presents a link performance study for mmWave systems at 60 GHz. The study is based on mmWave wireless modem measurements. The system performance is characterized by means of common metrics such as packet delivery rate, Signal to Noise Ratio (SNR) and throughput. The effect of spatial and polarisation diversity/multiplexing is explored, considering various modulation and coding schemes (MCS). Based on our findings, spatial diversity mostly impacts the quasi/non-Line-of-Sight (LoS) locations, whereas the gain from polarization diversity is more significant for horizontal polarized transmitters. Finally, results are compared to results from a channel measurements campaigns, performed at the University of Bristol at the same time, showing similar SNR trends, and thus empowering the validity of our results.


12:24 - Scalable Two-hop Relaying for mmWave Networks

Junquan Deng and Olav Tirkkonen (Aalto University, Finland); Tao Chen (VTT Technical Research Centre of Finland LTD, Finland); Navid Nikaein (Eurecom, France)

The performance of millimeter wave (mmWave) networks is limited by severe blocking effects. Mobile relaying exploiting possible two-hop line-of-sight connections is a strong candidate for coverage extension and consistent user experience in mmWave networks. Here, relaying based on opportunistic analog beamforming is investigated, and sets of fixed beams are used for cell discovery, relay discovery and data transmission. A low-complexity relay & beam discovery and selection protocol is considered. Communication performance and signaling overhead are estimated. To provide good relaying performance for cell-edge users without introducing high relaying overhead, a relay candidate set is selected by choosing a proper size, and suitable membership based on a utility function. Simulation results show that with relay candidate sets having a proper size, opportunistic two-hop mmWave relaying can achieve both high mean user performance and consistent user experience.


12:42 - Improving Device-to-Device Communications Pairing for Underlay Cellular Networks

Giovanni Giambene and Tran Anh Khoa (University of Siena, Italy)

Device-to-Device (D2D) communication is a promising technology for LTE-A and future 5G cellular systems to provide proximity services especially for public safety and emergency scenarios and to improve user experience as well as system capacity. We investigate here the underlay mode where CUEs and D2Ds can transmit on the same sub-channels inside a cell. This paper provides a model to evaluate the performance of D2D communications (sharing uplink resources with CUEs) and proposes a heuristic resource management scheme (combining a scheduler and a pairing strategy) to maximize the cell capacity while guaranteeing low outage probability values. This scheme (denoted as PF^2-OUT) adopts a proportional fairness scheduler for both CUEs and D2Ds and modifies the allocations to D2Ds in case these are causing outage for CUEs. The goodness of this heuristic scheme has been validated showing how its performance is quite close to an optimized scheme in the literature.