Every Phone, Plane and Satellite Obeys One Rulebook. It Is Rewritten Once Every Four Years.

by Arjun Mehta · August 31, 2026

Science & Technology Writer, The Globe Ledger

There is a book that decides whether your phone works when you land abroad, whether an aircraft's altimeter is drowned out by a mobile base station, and whether a weather satellite can still read the moisture in a cloud. It is called the Radio Regulations, it is a binding international treaty rather than a technical standard, and the International Telecommunication Union describes the current edition as binding 193 member states. It runs to four volumes and more than 2,000 pages, and it governs the radio spectrum from 8.3 kilohertz up to 3,000 gigahertz across more than forty categories of radiocommunication service.

The edition now in force is the 2024 one, which took effect on 1 January 2025. This year the ITU marks the 120th anniversary of the Radio Regulations, dating the series to 1906 — the year the first International Radiotelegraph Convention was signed in Berlin by 30 states, agreeing maritime communications and safety provisions and establishing "SOS" as the international distress signal. The engineering has changed beyond recognition. The underlying problem has not, because radio waves do not stop at borders and two transmitters on the same frequency in the same place produce nothing useful for either operator.

The measure of how well the arrangement works is unglamorous and rather striking. The ITU's backgrounder on spectrum management states that harmful interference concerns 1 in 5,000 assignments; the page does not date that figure, so it is best read as the ITU's own standing characterisation rather than a measurement tied to a particular year. For a shared physical resource used simultaneously by every government, airline, shipping company, broadcaster and mobile network on earth, that is a low failure rate, and it is the product of a filing system rather than any enforcement power of the ITU's own. Enforcement, where it happens, is done by national administrations.

How the book gets rewritten

Revisions happen at World Radiocommunication Conferences, held roughly every four years and running for four weeks. The most recent, WRC-23, met in Dubai from 20 November to 15 December 2023. According to the ITU, it drew more than 3,900 delegates from 163 member states, with 88 represented at ministerial level, and 151 member states signed the Final Acts. The ITU also recorded that 22 per cent of delegates were women, up from 18 per cent at WRC-19.

What such a conference produces is a set of amendments with immediate industrial consequences. WRC-23 identified new frequency bands for international mobile telecommunications — 3300 to 3400 MHz, 3600 to 3800 MHz, 4800 to 4990 MHz and 6425 to 7125 MHz — with the applicability of each varying by country and region. It agreed new frequencies for earth stations in motion, the terminals that deliver broadband to aircraft, ships, trains and vehicles. It allocated the 2 GHz and 2.6 GHz bands to high-altitude platform stations operating as mobile base stations, and it approved new usable orbital slots for satellite broadcasting for 41 countries.

The less commercial decisions are the ones that tend to matter longest. WRC-23 adopted a new resolution and a new treaty article recognising the importance of space-weather observations, modernised the Global Maritime Distress and Safety System, provisionally recognised the BeiDou satellite messaging service for use within that system pending the completion of coordination, and allocated the 117.975 to 137 MHz range for aeronautical mobile satellite communications. Closing the conference, ITU Secretary-General Doreen Bogdan-Martin said the conference had put the world on a solid path towards a more connected and sustainable digital future.

One structural feature explains most of the confusion about spectrum news. The world is divided into three ITU Regions, and many allocations and identifications apply only in one or two of them. "Global harmonisation" is therefore a direction of travel, not a description of the treaty. A band identified for mobile use in Region 1 may carry a different primary service in Region 2, which is why handset makers build radios that cover more bands than any single market uses.

The register that holds it together

Underneath the treaty sits an accounting system: the Master International Frequency Register, maintained by the ITU Radiocommunication Bureau. The ITU puts its holdings at 3.1 million terrestrial frequency assignments, with over 70,000 added every year, alongside more than 4.1 million assigned frequencies for space services, about 215,000 assigned frequencies in the broadcasting-satellite service and 15,000 allotted frequencies in the fixed-satellite service. The ITU's backgrounder does not date these totals, so they should be read as its most recent published characterisation rather than a year-end count. Disputes over how the rules apply go to the Radio Regulations Board, which the ITU describes as twelve elected members selected for their qualification, experience and regional representation, and which adopts the Rules of Procedure that interpret the treaty between conferences.

The register is not a picture of what is transmitting. It is a record of what administrations have filed and notified, submitted by governments on behalf of their operators, and its accuracy depends on those governments. That distinction is the single most useful thing to know when reading claims about how crowded the spectrum or the orbits have become.

Orbits, deadlines and warehousing

The gap between filings and reality became a policy problem in orbit first. The ITU notes that since 2011 it has received filings for frequency assignments to non-geostationary satellite systems composed of hundreds to thousands of satellites. Under the rules as they stood, an operator had a regulatory period in which to bring a filing into use, but nothing in that step required the constellation actually described in the filing to be built.

WRC-19 responded with a milestone-based approach: after the end of the regulatory period for bringing into use, an operator must deploy 10 per cent of its constellation within two years, 50 per cent within five and complete the deployment within seven. The ITU's stated purpose is to keep the Master Register a reasonable reflection of the actual deployment of such systems, striking a balance against the warehousing of radio-frequency spectrum — the practice of filing for far more capacity than an operator intends to build. The ITU backgrounder setting out these milestones was last updated in June 2021 and does not record any later amendment, so whether WRC-23 adjusted the regime is not something this source establishes.

It is worth being clear about what this regime is not. There is no world spectrum regulator. A band identified at a WRC is not a band any country must open; national regulators still decide what is licensed at home and on what terms, and the treaty is agreed by consensus among sovereign states, which is why conferences run long and outcomes are hedged with regional footnotes. Mario Maniewicz, director of the ITU Radiocommunication Bureau, described the updated treaty as providing a framework for national spectrum management that aligns with international standards — the word framework doing considerable work in that sentence.

The critique of the four-year cycle is straightforward and is made by industry participants themselves: hardware and network generations move faster than treaty conferences, so decisions taken in one decade constrain the products of the next. The defence is equally straightforward. A slower cycle is what makes long-lived infrastructure — aviation safety systems, meteorological satellites with decade-long build times, undersea and polar communications — investable at all. Both propositions can be true, and the tension between them is what a WRC actually negotiates.

Preparations for the next round are already running. WRC-27 will be held in Shanghai from 18 October to 12 November 2027, preceded by the Radiocommunication Assembly from 11 to 15 October. The conference preparatory process and the regional groups that assemble common positions are already at work, though the ITU's WRC-27 page names those preparatory meetings without publishing their dates. The ITU's own materials give its membership as 193 member states, alongside sector members drawn from industry, academia and other organisations, and by the time the delegates sit down, most of what they will agree will already have been settled in those regional rooms. The conference hall is where a rulebook older than broadcasting gets its next amendment — and where the terms on which the next decade of wireless technology is built are quietly fixed.