RAS1: Wireless Access

Wednesday, 9 June 2021, 11:30-13:00, Zoom Room

Session Chair: Filipe Sousa (Fraunhofer AICOS, Portugal)

Minimizing the Exposure Dose of Multi-Antenna Multi-Carrier System Users

Fabien Héliot and Tim Brown (University of Surrey, United Kingdom (Great Britain))
The impact of multi-antenna wireless personal devices (WPDs) on the individual electromagnetic field (EMF) exposure of users has yet to be properly understood at the system level. In this paper, we first explain how to model the exposure dose of multi-antenna WPD users in a multi-user multi-carrier communication system. This model is then used for minimizing the exposure dose, when considering quality of service (QoS) as well as transmit power requirements. In the process, we identify a new criterion, i.e. the ratio between the normalised exposure dose and the channel to noise ratio, as the main optimisation criterion for reducing the exposure dose of WPD users. Simulation results show that the usage of multi-antenna transmission can significantly reduce the exposure dose of WPD users in a multi-carrier system. An exposure reduction of at least 55\% is achieved when a two-transmit WPD is used instead of a single antenna WPD, while ensuring QoS.


Power Optimization and Throughput Enhancement in 6G Networks by Delay-Aware Resource Leverage

Silvio Mandelli, Alessandro Lieto, Andreas Weber and Thorsten Wild (Nokia Bell Labs, Germany)
While refining the specifics of the 5-th generation wireless standards, the research community is already shifting its attention towards new 6-th generation (6G) paradigms, like the “network of networks” topology. In that context, the sub-networks will be pivotal to support the advances of industrial internet of things or Industry 4.0, e.g. connecting an entire group of sensors and actuators of a robot. The unprecedented access points density in 6G sub-networks requires the design of schemes that can properly manage the interference. Targeting these high density scenarios, we describe the POLITE paradigm for Link Adaptation (LA) and power allocation which leverages all available radio resources to stabilize and reduce the interference. The Baseline Link Adaptation (BLA) schemes are compared with POLITE in their performance in a 3GPP-calibrated system level simulator for industrial scenarios. As services in industrial environments require high reliability under constrained delays, we propose delay-aware formulations in the POLITE design. In this work the emphasis is on the algorithmic implementation and performance assessment for generic delay requirements, leaving the investigation of extreme delay requirements for future work. Simulation results prove the benefits of POLITE in terms of increased throughput and delay satisfaction, with an overall reduced transmit power compared to the current BLA schemes.


Impact of Effective Antenna Pattern on Estimation of Interference in Citizens Broadband Radio Service

Kamil Bechta (Nokia Networks, Poland); Jinfeng Du (Nokia Bell Labs, USA); Marcin Rybakowski (Nokia, Poland)
This paper investigates the impact of antenna pattern modeling accuracy on performance evaluation in realistic Citizens Broadband Radio Service (CBRS) cellular networks. The current practice of using nominal antenna pattern of CBRS device (CBSD), as measured in anechoic chamber, for estimation of interference conditions between CBSDs does not address the antenna gain degradation and antenna pattern reshaping caused by angular spread in scattering propagation environment. System level simulations have been conducted using a model of commercially available antenna of CBSD in urban macro deployment scenario with full 3D channel model and proprietary algorithm for resources distribution. The result reveals that the value of interference between each pair of investigated CBSDs can be underestimated by 6 dB if nominal antenna pattern is assumed in link budget calculation instead of effective antenna pattern. This underestimation may lead to suboptimal channels distribution in real spectrum sharing environment of CBRS network and severe co-existence issues between CBSDs. Therefore, effective antenna pattern of CBSD, as determined for given scattering propagation conditions, should be used for more accurate modeling of interference during CBRS network planning, optimization, as well as network operation in spectrum sharing environment.


Optimal Split Bearer Control and Resource Allocation for Multi-Connectivity in 5G New Radio

Jocelyne Elias (University of Bologna, Italy); Fabio Martignon (University of Bergamo, Italy); Stefano Paris (Nokia Bell Labs & Université Paris Descartes, France)
Wireless cellular systems are evolving towards the integration of services and devices with a diverse set of throughput, latency, and reliability requirements. To this end, 3GPP has introduced Multi Connectivity (MC) as a more flexible architecture for 5G NR (New Radio), where multiple wireless connections can be used simultaneously to split or duplicate data traffic. While multi connectivity improves single user performance, the inherent increase of data transmissions on the wireless channel may result in higher interference, thus reducing the overall system performance. This paper analyzes the problem of admission control and resource allocation in multi connectivity scenarios, considering different requirements and 5G NR features. We formulate the problem as an optimization program and provide an heuristic approach to solve it. Numerical results in a realistic network deployment confirm that our solution can effectively allocate radio resources in order to increase admission rate and system throughput