“6G will not only transform industries through ultra-low latency and massive connectivity, it will also help bridge the digital divide by extending advanced services such as healthcare, education, and public safety to underserved communities.” – Nokia, 2023
Modulation for 6G Cellular
The evolution of cellular technology has always been tied closely to advances in radio modulation. Each generation of mobile communications has pushed the boundaries of how information is encoded onto electromagnetic waves. The first mobile systems relied on analogue modulation techniques, but as demand for efficiency grew, digital modulation strategies became the foundation of cellular design. With 6G cellular on the horizon, expected to emerge in the early 2030s, the question of modulation becomes critical again. This paper explores what modulation means in the 6G context, how it differs from previous generations, the techniques under consideration, and the implications for performance, reliability, and societal adoption.
Understanding Modulation in Cellular Systems
Modulation in telecommunications refers to the process of altering the characteristics of a carrier wave, typically its amplitude, frequency, or phase, in order to embed digital information. In simple terms, modulation is how voice, video, and data are impressed onto a radio frequency signal so it can travel through the air. For cellular systems, the choice of modulation impacts not only speed and spectral efficiency but also the coverage, energy consumption, and resilience of the network.
Earlier systems such as 2G relied on relatively simple forms like Gaussian Minimum Shift Keying. As bandwidth demands grew, higher-order Quadrature Amplitude Modulation (QAM) became standard. Today, in 5G deployments, 256-QAM and even experimental use of 1024-QAM are common, enabling extremely dense information packing in limited spectrum. However, there are diminishing returns. With 6G, the industry must reconsider modulation, since higher frequencies, new spectrum allocations, and novel requirements such as holographic communication and tactile internet demand a more adaptive and flexible approach.
Standards Timeframe
There is no single date for when 6G modulation becomes standard worldwide. Instead, the process is phased:
- Requirements and studies (2024–2026),
- Technical specification development (2027–2029),
- Formal standardization and commercial rollout (by 2030).
So, while modulation is not pinned to a specific day, by late 2028 / early 2029, we should expect finalized technical descriptions, including modulation schemes, for submission to the ITU. Full commercial use, incorporating those modulation designs, is expected around 2030.
This paper explores the currently known modulation options being investigated and developed for the next stages in the process. It does not offer what the final state for 6G modulation will be defined as a standard. As the process continues and evolves, you should check back here at http://www.vividcomm.com to learn more about 6G modulation.
The Frequency Landscape of 6G
One of the most significant aspects of 6G is the expansion into sub-Terahertz and Terahertz frequencies. These ranges, generally between 100 GHz and 1 THz, provide enormous amounts of bandwidth compared with current allocations. However, they come with substantial challenges, including high path loss, susceptibility to blockage, and short propagation distance. In this domain, traditional modulation techniques alone may not suffice. The need for new schemes that balance robustness with spectral efficiency is pressing.
At lower frequencies, 6G will continue to leverage evolved forms of Orthogonal Frequency Division Multiplexing (OFDM), which is the backbone of 4G and 5G. OFDM provides resistance to multipath interference and supports flexible allocation of spectrum resources. Yet, at higher bands, the overhead of cyclic prefixes and orthogonality requirements may be less attractive. This opens the door for alternative waveforms.
Candidate Modulation Schemes for 6G
The modulation strategies for 6G can be broadly divided into extensions of existing schemes and entirely new approaches. Among the extended strategies, higher-order QAM remains an option. By increasing the constellation size, more bits can be transmitted per symbol. For example, 2048-QAM or 4096-QAM could, in theory, be deployed. However, such schemes demand exceptionally high signal-to-noise ratios and precise channel conditions, which may only be achievable in short-range scenarios such as indoor ultra-high-speed wireless.
A more transformative candidate is Orthogonal Time Frequency Space (OTFS) modulation. OTFS maps information symbols into the delay-Doppler domain rather than the conventional time-frequency grid. This approach offers robustness against mobility and rapidly varying channels, which are expected in dense urban environments and vehicular applications of 6G. OTFS essentially transforms a time-varying channel into a quasi-static one, simplifying equalization and improving reliability.
Another key candidate is Index Modulation, where information is conveyed not only by traditional amplitude and phase changes but also by the choice of subcarriers, antennas, or time slots. Examples include Spatial Modulation and Subcarrier Index Modulation. These schemes improve spectral efficiency while potentially reducing hardware complexity.
Waveform innovations also play a role. Generalized Frequency Division Multiplexing (GFDM) and Filter Bank Multicarrier (FBMC) are being revisited for 6G because they offer reduced out-of-band emissions and better spectral localization than OFDM. This is essential when integrating fragmented spectrum or supporting new forms of dynamic spectrum sharing.
Modulation and Artificial Intelligence
An important dimension of 6G is the integration of artificial intelligence in real time. Unlike previous generations, where modulation was statically configured, 6G envisions adaptive modulation controlled by AI algorithms. Neural networks and reinforcement learning agents can evaluate channel conditions, user mobility, and network congestion, then select the optimal modulation scheme on the fly. This could mean switching between QAM, OTFS, and Index Modulation within milliseconds to ensure both reliability and efficiency.
Such adaptability is crucial for enabling applications like remote surgery, immersive extended reality, and autonomous transportation, where latency and reliability requirements are strict. In Canada, where networks must often cover vast rural areas as well as dense metropolitan centres, adaptive modulation guided by AI may ensure fair access to advanced services across diverse geographies.
Error Resilience and Energy Efficiency
In addition to raw throughput, 6G modulation strategies must address error resilience and energy efficiency. Higher-order modulation provides more bits per symbol but increases vulnerability to noise. Forward error correction techniques, such as Low-Density Parity-Check codes and Polar codes, will continue to be refined. However, modulation itself must contribute to resilience, perhaps through schemes that inherently tolerate fading and phase noise.
Energy efficiency is also central. Canada and other nations are striving for greener telecommunications infrastructure, and 6G modulation must be designed to minimize power consumption. This may involve adaptive constellation shaping, where symbols are distributed non-uniformly based on channel state information, reducing average transmit power without compromising performance.
Practical Challenges
Defining modulation for 6G is not purely a theoretical exercise. Hardware implementation is a challenge at Terahertz frequencies, where phase noise, amplifier linearity, and power efficiency become significant issues. Designing analogue-to-digital converters that can support high symbol rates with low error is another obstacle. Furthermore, global standardization will be required to ensure interoperability. The 3rd Generation Partnership Project (3GPP) will likely evaluate multiple candidate modulation schemes before settling on those suitable for widespread deployment.
Canadian researchers and institutions are active participants in this process. The National Research Council of Canada and several universities are contributing to the exploration of Terahertz communications, photonic technologies, and AI-driven modulation design. Their contributions may help shape a uniquely Canadian role in the global 6G landscape.
Canadian 6G Research Initiatives
Canada plays an active role in shaping 6G’s trajectory. In February 2024, Canada joined the United States, Australia, the Czech Republic, Finland, France, Japan, South Korea, Sweden, and the United Kingdom in endorsing a Joint Statement of Principles for 6G, affirming commitments to open, global, interoperable, secure, reliable, and resilient wireless technologies Canada.ca+2Foresight+2. This involvement builds on Canada’s Telecom Reliability Agenda and further aligns with supplier diversity and open‑RAN values Canada.ca.
A major boost comes from a CAD $634.8 million R&D investment by Ericsson in Canada, announced in November 2024. This funding supports R&D centres in Ottawa and Montréal, enhancing capabilities in AI‑powered network management, Cloud RAN, 5G Advanced, 6G exploration, quantum communication, and network APIs. The initiative also aims to foster partnerships with over 20 Canadian post‑secondary institutions Wilson Center+3ericsson.com+3Foresight+3.
At the institutional level, the Communications Research Centre Canada (CRC) in Ottawa serves as the federal hub for wireless R&D, advising on spectrum management, policy, and technology development Wikipedia.
In academia, Professor Melike Erol‑Kantarci at the University of Ottawa holds a Canada Research Chair in AI‑Enabled, Next‑Generation Wireless Networks. Her work spans AI and 6G systems, and she also collaborates with Ericsson as Strategic Product Manager for AI in Radio Access Networks Wikipedia+1.
Early efforts to foster 6G innovation include a 6G Research and Innovation Lab in Montréal, established through a collaboration among VMware, Mitacs, and IEEE. This centre focuses on integrating satellite, wireless and cloud technologies, and supports test-beds under the IEEE Future Networks Initiative’s Connecting the Unconnected challenge whatsyourtech.ca.
These initiatives collectively empower modulation research in Canada, enabling work on AI-driven adaptation, high-frequency waveform development, energy-efficient schemes, and policy alignment.
Implications for Society
The modulation strategies chosen for 6G will determine more than just technical performance. They will influence affordability, accessibility, and digital inclusion. For rural and Indigenous communities across Canada, modulation that maximizes coverage and robustness will be essential to bridge the digital divide. For cities, schemes that provide ultra-high capacity will fuel innovation in industries ranging from health care to entertainment. Modulation is thus a foundational enabler of social progress in the 6G era.
Summary
Defining modulation for 6G means blending evolution and innovation. High-order QAM and OFDM will continue alongside transformative methods like OTFS, index modulation, GFDM, and AI-adaptive selection. Yet implementation will require solutions for physical hardware, energy efficiency, and standardization. Canada contributes meaningfully via policy alignment, R&D investment (for example, Ericsson’s funding), government labs (CRC), academic leadership (such as Professor Erol-Kantarci), and innovation centres (Montréal lab). Together, these efforts support modulation strategies that promise resilient, efficient, and inclusive 6G for Canada and beyond.
As Ericsson has observed, “6G is expected to be standardized in 3GPP Release 21, around 2028, and globally designated as IMT-2030 by the ITU in 2030, enabling the first commercial deployments of 6G networks” (Ericsson, 2024). This underscores that the global definition of modulation for 6G is not a matter of speculation but a structured process, converging toward an internationally agreed framework by the decade’s end.
About the Author:
Michael Martin is the Vice President of Technology with Metercor Inc., a Smart Meter, IoT, and Smart City systems integrator based in Canada. He has more than 40 years of experience in systems design for applications that use broadband networks, optical fibre, wireless, and digital communications technologies. He is a business and technology consultant. He was a senior executive consultant for 15 years with IBM, where he worked in the GBS Global Center of Competency for Energy and Utilities and the GTS Global Center of Excellence for Energy and Utilities. He is a founding partner and President of MICAN Communications and before that was President of Comlink Systems Limited and Ensat Broadcast Services, Inc., both divisions of Cygnal Technologies Corporation (CYN: TSX).
Martin served on the Board of Directors for TeraGo Inc (TGO: TSX) and on the Board of Directors for Avante Logixx Inc. (XX: TSX.V). He has served as a Member, SCC ISO-IEC JTC 1/SC-41 – Internet of Things and related technologies, ISO – International Organization for Standardization, and as a member of the NIST SP 500-325 Fog Computing Conceptual Model, National Institute of Standards and Technology. He served on the Board of Governors of the University of Ontario Institute of Technology (UOIT) [now Ontario Tech University] and on the Board of Advisers of five different Colleges in Ontario – Centennial College, Humber College, George Brown College, Durham College, Ryerson Polytechnic University [now Toronto Metropolitan University]. For 16 years he served on the Board of the Society of Motion Picture and Television Engineers (SMPTE), Toronto Section.
He holds three master’s degrees, in business (MBA), communication (MA), and education (MEd). As well, he has three undergraduate diplomas and seven certifications in business, computer programming, internetworking, project management, media, photography, and communication technology. He has completed over 50 next generation MOOC (Massive Open Online Courses) continuous education in a wide variety of topics, including: Economics, Python Programming, Internet of Things, Cloud, Artificial Intelligence and Cognitive systems, Blockchain, Agile, Big Data, Design Thinking, Security, Indigenous Canada awareness, and more.