Does GSCN reflect offsettopointa and KSSB?

I’ve seen logs in SA it has offsettopointA.

So GSCN for NSA only, right?

You will find it only in SA and this will be delivered in 5G SIB1.

GSCN can be used for both brother but it is mainly designed for 5G SA.

Synchronization raster concept.

GSCN is not only for 5G SA.

Yes for both.

:point_down:

So if UE know SSB based on GSCN why to use offesttopointA?

UE doesn’t know the location of SSB in the channel bandwidth.

It needs to know the exact location in the channel bandwidth.

So this will be known through offsettopointA.

This GSCN should do it right?

As it’s giving the centre of SSB.

Center of SSB.

But still he dont where the SSB located in the channel bandwidth.

Channel bandwidth for example.

N78 100 Mhz.

GSCN if the center freq of ssb which is 20 MHz.

If UE knows the centre it can detect it easily.

No.

There is a big difference between SSB and channel bandwidth.

SSB is just 20 PRBs in frequency and 4 symbols in time.

Oh so offsettopointa to know where carrier start?

Exactly.

Look to the picture and you might figure out what I mean:

image

Illustration about 5G SSB Beam Sweeping, SSB Freq/time domain allocation methods, SSB Overhead Calculation, and SSB Related Parameters.

Thank you all.

One last question: In which message UE received GSCN?

In no message.

This is mapped on every UE by firmware.

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It dont receive it,

It blindly detect SSB position,

So GSCN is just theoretical meaning?

GSCN is used when UE is powered ON.

It scans all possible locations to find an SSB.

All possible locations are all possible GSCNs.

If is the center of SSB the GSCN.

For me It was a complicated subject, it takes time with me to understand it → 5G SSB Detailed Explanation (Theory + Practical + Configuration recommendation)

GSCN is a list of frequency points that can be used to transmit synchronisation signals.