Numerology in 5G — Lesson 3

This lesson covers the evolution of Air Interface towards 5G, focusing on the main unit of waveform in the 5th generation, the numerology. It explains the design and significance of subcarrier spacing and the impact of Doppler conditions and phase noise on inter carrier interference. The lesson also discusses the role of the guard interval in numerology and how it can be chosen for optimal deployment. It further explores the concept of link adaptation and the benefits of varying modulation. The lesson provides a comprehensive understanding of how different combinations of schemes can be used to maximize spectral efficiency in 5G communication systems.

Video Highlights

00:18 - Introduction and recap of previous lesson
06:41 - Variation in rms delay spread and GI overhead
08:50 - Problem analysis and proposal
14:02 - Variable guard interval or cyclic prefix
19:15 - Results of overhead reduction by changing guard interval
24:58 - Degree of freedom
27:45 - Low diversity channel condition
32:10 - single code rate

Key Takeaways

- The main unit of waveform in 5G is the numerology, which includes the design of subcarrier spacing and the guard interval.
- Doppler conditions and phase noise can lead to inter carrier interference, affecting signal power and interference power.
- The guard interval in numerology can be chosen based on deployment scenarios, and it plays a crucial role in maintaining the efficiency of the OFDM system.
- Link adaptation allows for the modulation and coding scheme to be adapted for each block, providing significant benefits in spectral efficiency.
- By appropriately clubbing a number of resource blocks or slots together, the spectral efficiency can be maximized in 5G communication systems.