High-level Overview of NR Release 15
![High-level Overview of NR Release 15](/content/images/size/w1200/2024/05/Highlevel-NR-Releease-15-2.png)
- The technical work of NR was initiated in 2016 as a study item in 3GPP release 14. The first specification of NR Release 15 was limited to non-standalone NR operation. See the below 3GPP timeline for 5G evolution to fulfill the 5G vision
![](https://www.mohamedeladawi.com/content/images/2024/05/image-6.png)
- 5G wireless access is being developed with three broad use case families in mind:
- Enhanced mobile broadband (eMBB)
- Massive machine-type communications (mMTC)
- Ultra-reliable low-latency communications (URLLC)
- NR Release 15 is the first version of NR. During the development, the focus was primarily on eMBB and URLCC Services to some extent.
![](https://www.mohamedeladawi.com/content/images/2024/05/image-5.png)
The 5G use cases and the other benefits offered compared to LTE are primarily related are the dependable on the following 3 key design principles:
- Higher-Frequency Operation and Spectrum Flexibility in which:
- It supports Licensed-spectrum operation from below 1 GHz up to 52.6 GHz.
- Operation at Higher-Frequencies in the mm-wave band offers the possibility for large amounts of spectrum and associated very wide transmission bandwidths .
![](https://www.mohamedeladawi.com/content/images/2024/05/image-3-1.png)
- Ultra-Lean Design where:
- It aims to Minimize always-on transmission, , thereby enabling higher network energy performance and reduces network operational expenses and enables higher achievable data rates.
- It offers flexibility in the Control Resource allocation leads to less power consumption.
- Forward Compatibility, where 3GPP agreed on some basic design principles summarized as below:
- Maximizing the amount of time and frequency resources that can be flexibly utilized or that can be left (Example reserved resources which can be used for LTE-NR Co-existence)
- Minimizing the transmission of always on-signals ( as explained in the Ultra-lean design).
- Confining signals and channels for physical layer functionalities within a configurable/allocable time/frequency resource.
![](https://www.mohamedeladawi.com/content/images/2024/05/Ultra-lean-design-1.png)
What are the fundamental technology pillars and components utilized in NR to realize the specified Use Cases and design principles?
- The following picture summarize the key technology components applied to NR:
- Transmission Scheme, BWP & NR Frame. i.e. Flexible Numerology
- Duplex Scheme. i.e. Dynamic TDD
- Low Latency support. i.e. Front Loaded DMRS
- Scheduling and Data Transmission. i.e. LDPC
- Control Channels. i.e. CORESET
- Beam Centric Design and Multi-Antenna Transmission. i.e. Beam Recovery
- Initial Access. i.e. Beam sweeping for SSB and RACH
- Interworking and LTE. i.e. Dynamic Spectrum Sharing
![](https://www.mohamedeladawi.com/content/images/2024/05/image-7-1-1.png)
Good References & Study Sources:
https://www.qualcomm.com/content/dam/qcomm-martech/dm-assets/documents/5G-NR-Release-15.pdf
5G NR: The Next Generation Wireless Access Technology- Page 57 to 70