As the 6G standard evolves, its development is a team effort. Global players across the United States, Europe and Asia, especially in China, Japan and South Korea, have a leading role to play in its realization.
Ultimately, the goal is to develop an integrated 6G system that supports communication across remote areas through reliable, high-speed connectivity. To achieve this, recent advances in digital modulation techniques for 6G are being investigated.
What is digital modulation?
Digital modulation describes the transmission of digital signals via analog transmission media (radio waves, telephone lines or fiber optic cables). Digital data (binary code) is embedded in a carrier wave by changing specific properties of the wave.
Along with the development of 6G also comes new techniques in digital modulation to enhance data transmission efficiency.
Digital modulation techniques for 6G
Recent advances in digital modulation techniques for 6G encompass a wide range of approaches, such as OTFS, ODDM, OCDM and AFDM, to address the unique challenges of next-generation wireless networks.
Orthogonal Time Frequency Space (OTFS) is a next-gen digital modulation technique designed to outperform the traditional modulation schemes like OFDM (Orthogonal Frequency-Division Multiplexing) used in 4G/5G. As a 2D modulation technique, it maps data in the delay-doppler domain using multipath reflections and motion effects. Since OTFS uses time and frequency dimensions to modulate data, it increases robustness against channel disturbances.
Orthogonal Delay Doppler Division Multiplexing (ODDM) considers doppler shifts, which makes it perfect for high-mobility applications. A doppler shift provides information about how fast an object is moving and in which direction. Consider an ambulance driving by: The faster it approaches, the brighter the sound. The faster it withdraws, the deeper the sound. Translated from radio to sound, higher tones indicate something coming toward you quickly. The lower the tone, the faster something is moving away from you.
Orthogonal Chirp Division Multiplexing (OCDM) uses chirp signals (frequency-swept waveforms) for encoding and data transmission. A chirp is defined as a signal whose frequency increases or decreases over time. It has a frequency-modulated waveform whose instantaneous frequency varies monotonically (linearly, exponentially or otherwise) with time. A benefit of using chirp signals is time-frequency diversity, meaning they are more robust to narrowband interference and multipath fading. OCDM shows great performance in disturbed channels. Also, good autocorrelation has advantages for timing and synchronization purposes. This modulation technique has good doppler resilience and handles fast-moving scenarios better.
Affine Frequency Division Multiplexing (AFDM) functions based on chirp signals as well. Symbols are distributed along time-frequency curved paths, which provides higher resilience against frequency selection and doppler shift.
JCAS and 6G enable integrated communication and sensing
The 6G spectrum is also making use of terahertz and radar frequencies, which sets it apart from 5G. These advanced frequencies will enable 6G to support joint communication and sensing (JCAS). This functionality is also known as joint sensing and communication, integrated sensing and communication, and integrated communication and sensing.
JCAS enables dual use of data transmission: The same signal can be used not only for transporting data but also for providing information about the environment, such as obstacles. During data transmission, a quality value indicates how good the transmission is. That value is used to determine whether there are obstacles along the transmission path and, if so, what they are.
Some terahertz frequencies are completely reflected or absorbed by certain materials. Therefore, it is not only possible to determine whether an obstacle is present, but also which material it is made of. In practical implementation, however, other factors play a role that influence functionality, such as humidity and dust.
Non-terrestrial networks to enable coverage in remote areas are also in discussion. Because 6G is currently in the development phase, those new features and capabilities are, at the moment, just promises of what’s to come. The excitement regarding the technological advances that can be achieved within the release cycles of the new mobile communications standard remains.
Get ready for a 6G future
As the industry looks to the future, recent advances in digital modulation techniques for 6G are driving innovation in global wireless communication.
Staying informed about these updates will be vital as you prepare to transition beyond 5G and want to make sure your networks remain robust, efficient and future-ready.
Belden’s complete connection solutions support the evolving needs of next-generation networks. We can help you adopt new technologies while maximizing the performance and reliability of your current infrastructure.
Learn more about how we collaborate.
Related links:
- 5G vs 6G: What are the main differences?
- Everything that Matters in Your 5G Deployment Now and in the Future
- 5G and TSN: Working Together to Meet Real-Time Requirements