5G New Radio Research Articles

Design of Low-Density Parity Check Codes for 5G New Radio

Turbo codes, prevalent in most modern cellular devices, are set to be replaced by LDPC codes as the code for forward error correction. This transition was ushered in mainly because of the high throughput demands for 5G New Radio (NR). The new channel coding solution also needs to support incremental-redundancy hybrid ARQ, and a wide range of blocklengths and coding rates, with stringent performance guarantees and minimal description complexity. In this article, we first briefly review the requirements of the new channel code for 5G NR. We then describe the LDPC code design philosophy and how the broad requirements of 5G NR channel coding led to the introduction of novel structural features in the code design, culminating in an LDPC code that satisfies all the demands of 5G NR.

3D MIMO for 5G NR: Several Observations from 32 to Massive 256 Antennas Based on Channel Measurement

By placing active antennas in a 2D grid at a BS, 3D MIMO is considered as a promising and practical technique for 5G New Radio (NR). So far, 3D MIMO studies reported are mostly done with antenna elements from 32 up to 128 in the limited scenario at one frequency. To gain further insights into the 3D massive MIMO channel and performance, field measurements from 32 to 256 antenna elements at the transmitter and 16 antenna elements at the receiver are performed in three typical deployment scenarios, including outdoor to indoor, urban microcell, and urban macrocell at both 3.5 and 6 GHz frequencies with 200 MHz bandwidth. Based on the extracted channel information from measured data, power angle spectrum, root mean square angle spread, channel capacity, and eigenvalue spread have been studied. Several observations, including 3D MIMO channel spatial dispersive properties and multi-user performance varying with antenna number, scenario, and frequency are given. These findings can provide valuable experimental insights for efficient utilization of 3D MIMO with massive antenna elements.

High-Speed Train Communications Standardization in 3GPP 5G NR

In 3GPP New Radio (NR), high-speed train (HST) is considered as one of the essential verticals in 5G applications. In this article, architectures and applications of 5G network slicing to HST are described. In addition, both higher layer and physical layer technologies are proposed to improve the quality of train communication in a 5G system. End-to-end network slicing that penetrates both the core network and radio access network can meet various performance requirements for 5G HST use cases, thanks to the flexibility offered by the proposed technologies. The higher layer technologies proposed in this article cover initial access, mobility management, and linear cell designs. Following the descriptions of evaluation parameters for the HST scenario adopted in 3GPP, the proposed physical layer technologies for HST applications including numerology and reference signal designs are explained. Link-level evaluation results are shown to demonstrate the superior performance of the proposed methods.

Modular and High-Resolution Channel State Information and Beam Management for 5G New Radio

This article provides an overview of key features pertaining to CSI reporting and beam management for the 5G New Radio (NR) currently being standardized in 3GPP. For CSI reporting, the modular design framework and high-resolution spatial information feedback offer not only flexibility in a host of use cases and deployment scenarios, but also improved average user throughput over state-of-the-art 4G LTE. To accommodate cellular communications in the milimeter-wave regime where a combination of analog and digital beamforming is typically used at both a base station and user equipment, beam management procedures such as measurement, reporting, and recovery are introduced. The utility and joint usage of these two features are demonstrated along with some potential upgrades for the next phase of 5G NR. Introduction

Analytic Hierarchy Processes for Spectrum Sharing in 5G New Radio Standard

The 5th Generation (5G) systems have the objective of delivering fiber like performance in a wireless environment. It is expected to connect all devices including mobile phones, cars, and home appliances and so on. Realization of the objective of the 5G systems needs a huge amount of spectrum. 5G new radio (NR) is the proposed standard for 5G that operates below 6 GHz (mid band 1–6 GHz) and above 6 GHz (high band at above 24 GHz). The unlicensed nature of spectrum enables simultaneous communication for anyone causing mutual interference between the operators. Solution to the problem of this interference and improvement to the performance of 5G NR are the subject of this paper done through analytic hierarchy process. Using this approach, user priority to access the spectrum is calculated without any conflict of interest among other secondary users. The simulation results show the feasibility of achievement of efficient spectrum utilization even with increase in the number of users in the systems.

On the Secrecy Capacity of 5G New Radio Networks

The new radio technology for the fifth‐generation wireless system has been extensively studied all over the world. Specifically, the air interface protocols for 5G radio access network will be standardized by the 3GPP in the coming years. In the next‐generation 5G new radio (NR) networks, millimeter wave (mmWave) communications will definitely play a critical role, as new NR air interface (AI) is up to 100 GHz just like mmWave. The rapid growth of mmWave systems poses a variety of challenges in physical layer (PHY) security. This paper investigates those challenges in the context of several 5G new radio communication technologies, including multiple‐input multiple‐output (MIMO) and nonorthogonal multiple access (NOMA). In particular, we introduce a ray‐tracing (RT) based 5G NR network channel model and reveal that the secrecy capacity in mmWave band widely depends on the richness of radio frequency (RF) environment through numerical experiments.

Mitigation of mutual exclusion problem in 5G new radio standards by token and non token based algorithms

The 5G new radio (NR) standards find application in the area of augmented reality, connecting massive internet of things devices and using mission critical applications with sub millisecond latency. A large volume of spectrum needs allocation to NR standards for realizing benefits. But this is not possible due to regulatory constraints. This creates a space for developing a new algorithm in spectrum sharing for the 5G NR standards. Conventional spectrum methods are affected by mutual exclusion issues. This paper discusses token-based and non-token based spectrum sharing methods which, it is believed, can help solving this problem. The results show that proposed techniques can efficiently mitigate the mutual exclusion problem seen in 5G NR standards.

Optimum Ultra-Reliable and Low Latency Communications in 5G New Radio

To satisfactorily gratify the scope of International Mobile Telecommunications 2020 (IMT-2020), 3GPP has launched the standardization activity of the fifth generation (5G) New Radio (NR) to deploy the first phase system (Release 15) in 2018 and the ready system (Release 16) in 2020. Different from the IMT-Advanced system solely enhancing the transmission data rates regardless the variety of emerging wireless traffic, the IMT-2020 system supports diverse wireless services including enhanced mobile broadband (eMBB), massive machine-type communications (mMTC) and ultra-reliable and low latency communications (URLCC) to fully capture wireless applications in 2020. Among all the wireless services, URLLC jointly demanding low latency and high reliability and mMTC emphasizing on high reliability create substantial impacts to the designs of NR air interface. On the advert of the conventional feedback based transmission in LTE/LTE-A designed for eMBB imposing potential inefficiency in supporting URLLC, in this paper, we revisit the feedbackless transmission framework, and reveal a tradeoff between these two transmission frameworks to latency and reliability guarantees. A multi-armed bandit (MAB) based reinforcement learning approach is therefore proposed to achieve the optimum harmonization of feedback and feedbackless transmissions. Our simulation results fully demonstrate the practicability of the proposed approach in supporting URLLC, to justify the potential of our approach in the practice of 5G NR.

Methodological issues in investigations of massage/bodywork therapy. Part II. Making research designs and data credible: model fit validity, combining scientific soundness with the explanatory model of massage and bodywork therapies☆

This work reports the implementation of a multiband 5G new radio (NR) fiber-wireless (FiWi) system, using analog radio over fiber (A-RoF) technology. Our approach employs a 12.5-km optical fronthaul (FH) for transporting fifth-generation of mobile network (5G) signals up to a remote antenna unit, from which 10-m reach wireless transmissions are performed aiming indoor and outdoor enhanced mobile broadband (eMBB) applications. The aforementioned 5G signals refer to a 5G NR standard at 26 GHz with 400-MHz bandwidth and DSP-based flexible-waveform signal at 3.5 GHz from our transceiver, which can be set as orthogonal frequency division multiplexing (OFDM), filtered-OFDM (F-OFDM) or generalized frequency division multiplexing (GFDM). Additionally, an investigation on the coexistence between 5G NR and Long Term Evolution-Advanced (LTE-A) standards in FiWi systems using the 700 MHz band, aimed for long-range applications, is reported. Experimental results demonstrate 1.65 Gbit/s total wireless throughput in accordance with the 3GPP Release 15 root mean square error vector magnitude (EVMRMS) digital performance requirements.