The upcoming generations of wireless communications are characterized by a wide variety of applications. This necessitates a provision of flexible radio access technologies (RATs) capable of adapting to changing user (and network) requirements. One of the most significant development in this regard is the introduction of mixed or multiple numerology concept for the fifth generation (5G) of wireless communication. However, flexibility offered by the mixed numerology concept comes with its own set of challenges, including the novel type of interference referred to as inter-numerology interference (INI). This chapter looks at the various implementation-related issues for 5G's mixed numerology systems such INI in particular. In addition to discussing the analytical models of INI, mechanisms for its mitigation are also described. Moreover, the generalization of numerology concept to other domains is briefly explored for future communication networks.

Chapter Contents:

• 3.1 Introduction
• 3.2 Mixed numerology multiplexing
• 3.2.1 Frequency domain
• 3.2.2 Time domain
• 3.3 Inter-numerology interference modeling
• 3.4 Factors affecting INI
• 3.4.1 Subcarrier spacing ratio, Q
• 3.4.2 Power offset
• 3.4.3 Channel response
• 3.5 INI management
• 3.5.1 Restructuring INI through common CP
• 3.5.1.1 INI analysis with common CP
• 3.5.2 INI-aware scheduling
• 3.5.3 INI-aware guard band allocation
• 3.6 Asynchronicity in the mixed numerology frame
• 3.7 Mixed numerology in single-carrier schemes
• 3.8 Summary
• References

Inspec keywords: OFDM modulation; cellular radio; radio access networks

Other keywords: upcoming generations; INI; changing user; future communication networks; implementation-related issues; mixed numerology concept; interference issues; flexible radio access technologies; wireless communication; mixed numerology systems; inter-numerology interference; multiple numerology concept

Subjects: Radio access systems; Radio links and equipment; Mobile radio systems; Modulation and coding methods