nsa nr

Non-Standalone (NSA) New Radio (NR) refers to a deployment mode for 5G networks where the 5G NR radio access network (RAN) is introduced alongside the existing LTE (Long-Term Evolution) core network. In an NSA NR deployment, the 5G NR provides enhanced data rates and capabilities, while the LTE core network handles certain control functions. This allows for the early rollout of 5G services without a complete overhaul of the entire network architecture.
Let's delve into the technical details of NSA NR:
- Dual Connectivity:
- NSA NR enables dual connectivity, allowing a device to be simultaneously connected to both the 5G NR and LTE networks. This dual connectivity allows for seamless handover and mobility management between the two networks.
- Control Plane and User Plane Split:
- Similar to NSA LTE, the control plane and user plane functions are split between LTE and 5G NR.
- The control plane functions, including signaling and mobility management, are handled by the existing LTE core network. The 5G NR RAN is responsible for the user plane, carrying the actual data traffic.
- NG-RAN (Next-Generation Radio Access Network):
- The introduction of 5G NR within the RAN provides higher data rates, lower latency, and improved spectral efficiency compared to LTE.
- NR cells work alongside LTE cells to provide connectivity to user devices. NR cells can operate in both Frequency Range 1 (FR1) and Frequency Range 2 (FR2) to cover sub-6 GHz and mmWave frequencies, respectively.
- Primary Cell (PCell) and Secondary Cell (SCell):
- In NSA NR, the 5G NR cell serving the device is referred to as the Primary Cell (PCell). The LTE cell supporting the device is called the Secondary Cell (SCell).
- The PCell anchors the connection, handling the control plane and anchoring the user plane. SCells can be dynamically added or released based on network conditions to enhance data rates or coverage.
- Carrier Aggregation:
- NSA NR supports carrier aggregation, allowing the aggregation of LTE and 5G NR carriers to provide increased data rates.
- Carrier aggregation enables the simultaneous use of multiple frequency bands in both LTE and NR, leveraging the available spectrum efficiently.
- Interworking and Seamless Handover:
- The interworking between LTE and NR ensures seamless mobility, allowing a device to move between LTE and 5G NR coverage areas without service disruption.
- Handover procedures are optimized to maintain a continuous connection as devices transition between LTE and NR cells.
- Deployment Flexibility:
- NSA NR provides network operators with flexibility in deploying 5G services, allowing for a gradual introduction of 5G capabilities without an immediate need to replace the entire core network infrastructure.
It's important to note that NSA NR is an interim deployment mode, and the long-term vision is to move towards Standalone (SA) 5G networks where the 5G core network is fully independent of LTE. This transition is expected as the 5G ecosystem matures and becomes more widely adopted.