CBRA RACH SR % and RACH SR % average values

To 5G Experts:
Just want to know what is average day level /network level kpi performance for CBRA RACH SR % in your network.
For Mid-Band 3.5 and in case any network using Dynamic Spectrum Sharing on Lower Band like NR 2.1 or NR700 something like that, what ss RACH SR % performance on day level.

This is low level KPI and it depends very much of the B1 threshold.
Values like 60-70% SR are common.


This is my network Intial RACH SR % for Mid-Band Vs Low-Band:

Its about 25 % Average SR % for Mid-Band.
For lower NR band approx. 8 %.

It depends on your B1 threshold. :slight_smile:

B1 is -110 dBm currently.

You must get a lot of SCG failures during drive test due to RACH problem.
Do you have contiguous 5G coverage or just spots here and there?

Yes, it’s true.

A single UE in a wrong position could make a mess on RACH SR.

SCG failue with different cause code usually during drive test logs analysis.
For example, SCG failure due to SCell change, T310 expiry, Max retransmission reach, etc.

All of those means you are targeting too much coverage.

Almost Continue Coverage - almost all 4G have 5G now.

For the RF plan that you have.
Low band means what band? 700MHz?

NR 2.1 Currently.
ESS currently configure with LTE 2.1.

What is the ss-block pbch power?
It is in RRC reconfig message for NSA.
18 or 21 dBm? Or 15?


So you are expecting to deal with a pathloss of up to 125 dBm for RACH.

In Ericsson you can not adjust SSB Block power.

Yes, I know. You cannot adjust it. :slight_smile:

Can you please elaborate 125 dBm?
And what is end benefit?

You will see during drive test that your UE has NR PUCCH power at 20 dBm most of the time.
This is a very clear indication that the link budget is limited in uplink and you are targeting too much coverage.
Path loss for RACH = 15 dBm - (-110dBm) = 125 dBm.
Also you will see in drive test analysis that UE fail to transmit during 10 preambles because it reaches 20 dBm power limit.
So RACH procedure will fail at message2
Is it DSS 5G NSA?