5G NSA-to-SA Reconstruction Guide(Post + Video)

5G NSA-to-SA Reconstruction Guide(Post + Video)

In this post, we will have a quick guide regarding 5G Standalone deployment, and we will go through some considerations which should be well thought-out in the initial phase of 5G Standalone. The following points will be covered in this video.

Since, Most of the 5G Networks operate with 5G NSA – Option 3X, which utilizes both 4G RAN and Core to offer 5G services, as 4G is being used as anchoring to handle related 5G signaling. That is why It`s called Non-stand-alone, as it relies on the 4G legacy to operate, so is deploying 5G Stand-alone Option 2 recommended at the current stage?

To smooth the transition between 5G NSA to 5G SA, it is recommended to use a Mixed/Hybrid 5G Network to keep both 5G SA and NSA operating together. Moving to 5G SA directly- Option 2 is not recommended at the current stage of the 5G network due to devices, which not yet support 5G SA. However, in the end, this is more relies on each operator's vision and business.

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What are the Main requirements from RAN Side during 5G NSA-SA reconstruction?

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(1) SSB Frequency position identification method change

SSB Frequency domain position can be defined by two types, which are NR-ARFCN (New Radio absolute channel number) and GSCN (Global synchronization Channel Number); both are being used to locate the Synchronization signal / physical broadcast channel block position in the frequency domain.

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If NR-ARFCN is currently being used in your current 5G NSA network, then it is mandatory to change it to the GSCN method as it supports both 5G NSA & SA, While ARFCN only supports NSA

GSCN “Synchronization raster is used in 5G SA as it has a faster and more effective band scan and relatively low resolution, which helps reduce the number of SSB positions that can be scanned by the Device during initial access.

It is recommended to use GSCN during NSA deployment to avoid unnecessary frequency change during NSA –SA network deployment.


System Information Block 1 is mandatory for 5G Standalone

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Xn/NG interfaces must be defined

  • Xn Interface between gNB <---> gNB related IPs need to be defined.
  • NG Interface between 5G Core <---> g-NB related Control plane and user plane IPs must be defined.
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