World Radiocommunication Conference Research Articles

Coexistence of 5G/6G and Digital Terrestrial Television Networks

This paper analyzes practical solutions for implementing 5G/6G and Digital Terrestrial Television (DTT) network coexistence in the UHF band. Two potential scenarios are explored using the case study of a nationwide DTT network: spectrum splitting and spectrum interleaving. Both scenarios are thoroughly examined based on current UHF spectrum usage and the DTT network structure based on a case study of Poland. The analysis includes potential future benefits and limitations of each scenario. The results presented in this paper can guide administrations in implementing decisions made at the International Telecommunication Union—Radiocommunication Sector, World Radiocommunication Conference 2023 (ITU-R WRC23), improving spectrum efficiency and 5G/6G networks development.

Adjacent-Channel Compatibility Analysis of International Mobile Telecommunications Downlink and Digital Terrestrial Television Broadcasting Reception in the 470–694 MHz Frequency Band Using Monte Carlo Simulation

This paper delves into the imperative need for coexistence and compatibility in the 470–694 MHz frequency band, as mandated by the World Radiocommunication Conference 2015 (WRC-15) and the WRC-23. It focuses on challenges in the coexistence of Digital Terrestrial Television Broadcasting (DTTB) and International Mobile Telecommunications-2020 (IMT-2020) services in downlink-only mode, particularly in adjacent-channel scenarios. Using Monte Carlo simulations, the study evaluates the probability of interference from IMT base stations with DTTB reception. The analysis thoroughly investigates the impact of the IMT transmitter’s Adjacent Channel Leakage Ratio (ACLR) and the DTTB receiver’s Adjacent-Channel Selectivity (ACS) on the probability of interference. The results demonstrate a significant degradation in the DTTB reception probability at the edge of coverage based on standard assumptions. To address these challenges, this paper provides recommendations for mitigating interference. These include defining enhanced ACLR regulations for IMT base stations, implementing antenna discriminations, providing specialized filters, and establishing national coordination procedures. The research provides valuable insights for informed decision making in spectrum management within the 470–694 MHz band, aiming to facilitate the coexistence of DTTB and IMT-2020 services, in line with international regulations and best practices.

World Radiocommunications Conference 2023, WRC-23

World Radiocommunications Conference 2023, WRC-23

Co-Channel Compatibility Analysis of IMT Networks and Digital Terrestrial Television Broadcasting in the Frequency Range 470-694 MHz Based on Monte Carlo Simulation.

According to Resolution 235 adopted during the World Radiocommunication Conference 2015 (WRC-15) and the preliminary agenda item 1.5 of WRC-2023, the International Telecommunication Union Radiocommunication Sector (ITU-R) has been entrusted to carry out sharing and compatibility studies between broadcasting and mobile services in the frequency range 470-694 MHz in Region 1. This study specifically focuses on evaluating electromagnetic compatibility in potential co-channel sharing scenarios between Digital Terrestrial Television Broadcasting (DTTB) and International Mobile Telecommunications (IMT) systems within the 470-694 MHz frequency band that may arise in the foreseeable future. To assess the conditions for coexistence, a Monte Carlo simulation method implemented through the SEAMCAT software version 5.4.2 is employed, examining six potential interference scenarios. The simulation results yield the minimum coordination distance required between IMT and DTTB services in the 470-694 MHz band based on the protection criteria to ensure harmonious coexistence while maintaining satisfactory performance. Furthermore, the study investigates the impact of various factors such as transmitter power, antenna heights, coverage radius, antenna discrimination, and antenna tilt angle on the separation distances. The focus lies primarily on critical interference scenarios across neighboring countries' borders. The simulation outcomes confirm that sharing the same frequency band between IMT and DTTB networks would result in significant mutual interference. Nevertheless, carefully analyzing diverse parameters and assumptions helped provide recommendations to reduce the required separation distances. These findings are valuable for broadcasters, mobile operators, and regulators in establishing the technical coexistence conditions for DTTB and IMT in the new band.

Trends in Aeronautical Flight Test Telemetry

Based on Action Item 1.5 and the relevant investigations and studies, the World Radio communication Conference (WRC 2007) decided upon new additional frequency spectrum allocations for Aeronautical Mobile Telemetry (AMT).
 Four new frequency bands in the range from 4400 to 6700 MHz have been allocated to the Aeronautical Mobile Service (AMS) on a co-primary basis, limited to AMT for flight testing by aircraft stations. The range from 5091 to 5150 MHz may be used worldwide, allowing the implication of wide band telemetry links and helping the international cooperation and standardization in flight test missions.
 After reviewing the resolutions COM 4/2 and COM 4/7 of the WRC 2007 it is realized that C-Band becomes an attractive band for AMT. Components and systems for either new state-of-the-art equipment or for the upgrade of existing systems (in L-or S-Band) are already in work. One area of concern requiring an up front evaluation is tracking algorithms and mechanical tracking systems that operate specifically in C-Band. Future planning to greater utilize this band is presented.

WRC-23 on the Horizon: Large Satellite Constellations, ITU Issues, and Industry Perspective

Although the previous World Radiocommunications Conference (WRC-19) attempted to resolve spectrum-sharing issues among the disparate new satellite constellations, issues have multiplied as these constellations are coming into use before all the rules have been created. The upcoming WRC, to be held at the end of 2023, will grapple with spectrum and situational sharing issues among constellations that are larger than ever before, and that are disrupting national regimes designed for licensing more traditional, one-at-a-time geostationary satellites. The agenda for WRC-27 will surely include multiple areas of study related to constellations, and the International Telecommunication Union (ITU) will need to work closely with the UN’s Office of Outer Space Affairs (UNOOSA) to resolve situational issues such as traffic management, debris, and the sustainability of the outer space environment. The emergence of operational constellations is disrupting legal regimes for states and industrial players, and future Agenda Items (AIs) should be added to WRC-27 or future Committee on the Peaceful Uses of Outer Space (COPUOS) sessions. constellations, LEO, ITU, spectrum, WRC

Analysis of the WRC-23 Agenda Item Concerning the Future Use of the 470-694 MHz Band in Europe

The upcoming World Radiocommunication Conference 2023 (WRC-23), according to the preliminary agenda item 1.5, will decide the long-term use of the 470-694 MHz band in International Telecommunication Union Region 1 and consider regulatory actions for the rest of the decade. This article attempts to inform the debate on the future use of spectrum in the 470- 694 MHz band and the status of broadcasting services at the European level and in many individual member states. This article highlights the role WRCs played by allocation of the previous digital dividend bands for mobile services. It provides an overview of the most recent trends and developments of existing services in the sub-700 MHz band. The article also explores and analyzes options for future use of the 470-694 MHz band in Europe and discusses the benefits and implications of adopting each option. Based on this analysis, it is recommended to introduce a secondary allocation to mobile service in the downlink-only mode alongside traditional broadcasting services in the sub-700 MHz band at the upcoming WRC-23.

An Update From the North American Broadcasters Association and the World Broadcasting Unions’ Committees

The North American Broadcasters Association’s Technical Committee (NABA-TC) plays a key role in ensuring that the technical needs and goals of our members are addressed in the complex, rapidly changing technical environment of broadcasting and content distribution. NABA’s TC works to ensure that North American broadcasting interests are represented well in key international forums. A delegation representing NABA positions participates in Working Group meetings and World Radio communication Conferences (WRCs) of the International Telecommunication Union’s Radiocommunication Sector (ITU-R), the U.N. agency with legal authority over the world radio spectrum allocations and recommendations.

Long‐Term Rain Attenuation Measurement for Short‐Range mmWave Fixed Link Using DSD and ITU‐R Prediction Models

AbstractSeveral millimeter Wave (mmWave) bands, which suffer from rain attenuation, were identified in the World Radiocommunication Conference 2019 (WRC‐19) for fifth generation (5G) radio networks. In this paper, long‐term attenuation is measured over typical building to building radio links in the built environment, which constitute two 36 m links along a direct link and an indirect side link at 25.84 and 77.54 GHz and a 200 m link at 77.125 GHz. The attenuation was also estimated using precipitation data from a high end accurate disdrometer weather station using the drop size distribution and the International Telecommunication Union (ITU) models. The results indicate that attenuation using Mie theory is in agreement with the ITU model for most of the rainfall events; with higher attenuation being measured than predicted when snow grains and raindrops mix. Raindrops with diameter between 0.1 and 4 mm indicate that the dominant raindrops have considerable influence on the measured attenuation, especially at light and moderate rainfall events. The maximum distance factor restriction of 2.5 in ITU‐R P.530‐17 is shown not to be suitable for short‐range fixed links as it excessively underestimates attenuation.

Downlink Cofrequency Interference Analysis of Vehicles and UAV Network in Ka Band

With the rapid development of radio and computer technologies, the application scenarios of UAV carrying computer flight control systems are becoming more and more abundant. UAV can form a collaborative network with ground IoV (Internet of Vehicle) to improve the link quality of vehicle signals in some environments with poor network connectivity. For UAV and ground vehicles that are far apart, satellites can assist in the transmission of data between them. UAVs are allowed to be included in the satellite communication network in the Ka band in the 2015 World Radiocommunication Conference. In order to avoid the interference with existing communication services in the Ka band, it is necessary to limit the flying height of the UAV. This article will study the frequency compatibility between UAV and Internet of Vehicles in the same-frequency band. First, model the propagation environment of the UAV transmitting signal is modeled and the path loss of it is calculated, including the basic transmission loss in free space of the signal and the atmospheric propagation loss when the signal passes through the atmosphere. Then the radiation pattern of the receiving antenna is modeled, which is a 4 × 2 antenna array in this article, and the total antenna gain is obtained by adding the element gain and the array gain. Finally, the interference between UAV and Internet of Vehicles is simulated, calculating the interference and noise ratio of UAV to the Internet of Vehicles under different pointing angles between the interference and the interfered antenna and different elevation angles from UAV to the GSO satellite. Finally, the safe separation distance to protect the Internet of Vehicles from interference is got.

Agenda Items of the World Radiocommunication Conference 2023 With a Potential Impact on Microwave Remote Sensing [Technical Committees

Presents information on the 2023 World Radiocommunication Conference.

High-Altitude Platform Stations as IMT Base Stations: Connectivity from the Stratosphere

High-altitude platform station (HAPS) as International Mobile Telecommunications (IMT) base station (HIBS) has been attracting the attention of aerospace and telecommunication companies from many countries in recent years. The HIBS' remarkable differential feature is the possibility of using HAPS to complement the IMT terrestrial coverage, benefiting from the platforms being located in the stratosphere, enabling much wider coverage when compared to conventional terrestrial solutions. In addition, the COVID-19 pandemic has highlighted the technological and social differences among countries, mainly due to the poor quality, or even absence, of Internet connectivity. HIBSs might efficiently support reducing the digital divide, since they provide connectivity to the same mobile devices as the terrestrial networks, which allows this non-terrestrial connectivity solution to increase global coverage and expand mobile connectivity for everyone. This article describes the fundamentals of the HIBS, as well as its deployment scenarios and regulatory aspects. Furthermore, it is reported, for the first time in the literature, a coexistence analysis between HIBS and fixed services point-to-point (FS-PP), as an International Telecommunication Union - Radio-communication Sector preparatory study for the support of decisions to be made at the 2023 World Radiocommunication Conference. The simulations demonstrate the feasibility of coexistence between HIBS and FS-PP active links, sharing the HIBS Band 2 around 2 GHz.

Review of antenna technologies for very high frequency Data Exchange Systems

SummaryThe Automated Identification System (AIS) was originally developed as a terrestrial system tracking vessels near the coastline. Dedicated channels were allocated within the spectrum historically reserved for maritime applications in the very high frequency (VHF) band, enabling long range communications, up to a few kilometers. There have been various initiatives in the last decade that extended this system with a space segment, enabling global monitoring of vessels beyond the range of terrestrial stations. Recently, the World Radiocommunication Conference has allocated frequencies for the extension of this system to a two‐way VHF Data Exchange System (VDES) via satellite. This requires to adapt spaceborne antenna solutions previously developed for AIS, particularly for missions using small satellites and CubeSats. This paper provides a timely review of existing VHF antenna solutions and new concepts under development which could be applicable to VDES missions. Some key metrics are identified to provide a comparative study between various candidate solutions. Considering the range of possible missions, from secondary payloads on‐board larger satellites to dedicated constellations, it is believed that a number of antenna products can find application in future VDES space‐based infrastructure.

Design of Minkowski Array Microstrip Fractal Antenna at 3.5 GHz Frequency for 5G Communication System

Technological developments in the field of telecommunications are experiencing rapid progress, especially the presence of 5G technology as a fifth generation cellular communication system that has many advantages at the World Radiocommunication Conference (WRC) in 2015, 5G candidate frequency bands below 6 GHz have been widely discussed, and the range the following frequencies have been suggested: 470–694, 1427–1518, 3300–3800, and 4500–4990 MHz. One of recommendation of resonant frequency is 3.5 GHz, as it is acceptable in most countries. Therefore, a reliable communication network is needed, especially in the 3.5 GHz frequency band for fifth generation applications. Antena is one of the important communication components in radio communication system. Mikrostrip Antena is a type of Antena that is currently growing because it has the advantage of having a light weight and low profile. This paper proposed development of mikrostrip Antena using the fractal method, increase the gain using the Array method, and achieve the target return loss ≤ -10 dB, VSWR ≤ 2, and gain ≥ 5 dB at frequency of 3.5 GHz for 5G communication sytsem. Proposed Antena is designed using a duroid R5880 substrate with a dielectric constant value of 2.2, a dielectric loss (tan loss) of 0.0009 and a substrate thickness (h) of 1.57 mm. This study resulted in a reduction in Antena dimensions until 53.76% with return loss of -42.48 dB, VSWR 1.02, and a gain of 8.46 dB. The results obtained in this design meet the specifications of the predetermined targets.

5 G communication network signal propagation models

The next generation 5G / IMT-2020 technology, like any new technology, brings its own specific features to all aspects related to the practice of its application. One of these particularly important aspects is electromagnetic compatibility. At the stage of preparation for the introduction of 5G radio networks, called NewRadio, it is necessary to take early measures to assess effectively the electromagnetic compatibility conditions for these networks based on a thorough analysis of the features of 5G technology. Correct and accurate assessments of these conditions means successful provision of the electromagnetic compatibility of radio equipment of new networks.
 The World Radio Communication Conference WRC-15 identified new radio frequency bands for 5G, including centimeter and millimeter wave bands. In general, this RF spectrum is located in three regions: below 1 GHz, 1 GHz to 6 GHz, and above 6 GHz (up to 100 GHz). From the EMC standpoint, the following can be distinguished as the main features of this spectrum: different nature of losses during signal propagation, in particular, a significant influence of additional factors (gases – oxygen, water vapor, etc.) on the level of losses previously unknown in cellular communication.
 The mathematical model of signal propagation of 5 G communication networks has been developed which takes into account: the attenuation of signals in free space; attenuation of signals caused by the influence of walls and floor slabs, loss of signal energy, when space is filled with various objects; attenuation of signals caused by loss of energy of radio waves, when propagating through rains; signal attenuation due to loss of radio wave energy due to fog; signal attenuation, when propagating through tree leaves, slow and fast random fading.

Compatibility between EESS (passive) in band 23.6–24 GHz and 5G in band 24.25–27.5 GHz

The 24.25–27.5 GHz band was allocated to IMT (International Mobile Telecommunication) during the World Radiocommunication Conference (WRC) after studies were elaborated between this potential allocation and the services in adjacent band and in particular with Earth Exploration by satellite in adjacent band. Several studies were evaluated during the WRC-19 cycle. This document describes only the studies undertaken by some European states for the protection of Earth exploration by satellite. The elements provided in this document are the basis of the European position for WRC-19 on the protection of passive EESS in 23.6–24 GHz.

Erratum to “Interference management in 6G space and terrestrial integrated networks: Challenges and approaches”

One sentence “In the International Telecommunication Union Radiocommunication Sector, the frequency sharing issues between the satellite and terrestrial communication networks in the millimeterwave band have been acknowledged and were reported at the 2019 World Radiocommunication Conference” at Page 272 in the article “Interference management in 6G space and terrestrial integrated networks: Challenges and approaches <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> ” which appeared in vol. 1, no. 3 of Intelligent and Converged Networks, was not correct in the published version.

Overview of Intelligent Transport System (ITS) and Its Applications

Since last decades world, predominantly urban areas, is experiencing huge voluminous road traffic growth, resulting in heavy congestion, air pollution, accidents, and poor efficiency. Many people every day are the victims of this poor management of tremendous traffic. Since many years, there had been some automation in managing the traffic namely Electronic Toll Collection (ETC), Electronic parking payment, normal traffic information etc. However, there are little efforts for making the system more advanced. Recently, several kinds of research are being launched by many countries to develop Intelligent Transport System (ITS), with the objectives to minimize congestion, ensure better safety, reduce air pollution etc. ITS are planned to establish robust communication between vehicle to vehicle (V2V), vehicle to pedestrian (V2P), vehicle to infrastructure (V2I), and vehicle to network (V2N). Initially, for communication links ITS, deploys Wi-Fi network, but because of limited capacity and huge requirement, some links use 5.8 GHz radio frequency for such purposes. IEEE, International Telecommunications Union (ITU) and other advanced research organisations are studying 700 MHz band and mm frequency bands for advanced ITS. ITS is poised to use Information &amp; Communication Technology (ICT) networks for such purposes. ITU has established Study Groups/study questions for addressing ITS issues. The World Radio Conference (WRC-2019) has made a Recommendation 208 regarding harmonization of frequency bands for ITS applications. This paper presents a comprehensive overview of ITS, its applications and analysis etc. The radio frequency spectrum aspects and role of 5 G in ITS are also described in detail.

How Can Microwave Observations at 23.8 GHz Help in Acquiring Water Vapor in the Atmosphere over Land?

Due to concerns about radio frequency interference from emerging telecommunications technology, there have been intensive discussions on the changes to the international Radio Regulations around 24 GHz at the recent World Radiocommunication Conference in 2019. Although the sensitivity to total precipitable water (TPW) at 23.8 GHz over land is small, and in some cases close to zero, state-of-the-art retrieval systems with no dependence on real-time ancillary data (e.g., numerical weather prediction (NWP) model forecasts), such as the National Oceanic and Atmospheric Administration (NOAA) operational Microwave Integrated Retrieval System (MiRS), have been producing reliable TPW products over both ocean and land, which implies that the microwave channel at 23.8 GHz is providing valuable information on TPW over land as well as over ocean. The contradiction between the zero or near-zero sensitivity and practical performance over land raises questions for the remote sensing community and public users of such data. In this study, we examine the underlying physics and include mathematical explanations, which address and clarify the apparent contradiction. The channel at 23.8 GHz is a direct measurement and indispensable for its combined use with microwave temperature and moisture sounding channels.

Вопросы радиочастотного обеспечения космических систем на основемногоспутниковых группировок с учетом требований МСЭ-R и результатов ВКР-19

Deployment of space systems based on multi-satellite constellations to provide broadband Internet access and communication services acutely raises the question of their radio frequency support including issues of electromagnetic compatibility (EMC) between competing space systems using multi-satellite constellations (StarLink, OneWeb, Kuiper, etc.), their EMC with traditional space systems (satellite communication systems that employ spacecraft in geostationary and non-geostationary orbits, space systems of other services), as well as regulatory issues of entering into service and staged deployment of space systems. The article formulates the problematic issues of radio frequency support of modern space systems taking into account the trends of satellite constellations deployment and proposes the solutions with consideration to international and national requirements in the regulation of radio frequency spectrum including the ITU requirements and the requirements of Russian State Commission for Radio Frequencies. The paper shows the ways to share the radio frequency spectrum to meet new requirements of the World Radiocommunication Conference 2019 (WRC-19).