What is the formula for Cell ID (NCI) in 5G NR networks?

5G NR
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Hello dears…

Just like as seen here LTE: What is the formula for Cell ID (ECI) in LTE networks? - #13, what is the calculations for NCI in 5G NR networks?

Updated with @AlexB answer… Thanks, great site there. :wink:
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NR Cell Identity (NCI) and NR Cell Global Identity (NCGI) |R15|

The NR Cell Global Identity (NCGI) shall be composed of the concatenation of the PLMN Identifier (PLMN-Id) and the NR Cell Identity (NCI) as shown in Figure 19.6A-1 and shall be globally unique:

Reproduction of 3GPP TS 23.003, Figure 19.6A-1: Structure of NR Cell Global Identity

Figure 19.6A-1: Structure of NR Cell Global Identity

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The NCI shall be of fixed length of 36 bits and shall be coded using full hexadecimal representation. The exact coding of the NCI is the responsibility of each PLMN operator.For more details on NCI and NCGI, see TS 38.413.

NOTE:

In the 5G Core Network protocols, when the NCGI needs to be identified in the context of Standalone Non-Public Networks (SNPN), the Network Identifier (NID) of the SNPN is included as part of the NCGI Information Element (see TS 29.571); this is a protocol aspect that does not imply any change on the system-wide definition of the NCGI.

Source: inside TS 23.003: Identifiers for EPC (cont'd)

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Great site, thanks @AlexB

But do you have rules like 5G NCI (Like LTE ECI = 256 * eNBId + Cellid)?

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You can use calculation for gnb I’d here 5G NR GNB ID Calculator

The text describes how the calculation is done.

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ttps://nrcalculator.firebaseapp.com/nrgnbidcalc.html

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Nice table CGI decomposition into site_ID and Cell_ID for all technologies.

It consolidates all needed formulas to extract site_ID and cell_ID for all technologies as shown below.

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LinkedIn: Fathi Farouk on LinkedIn: #optimization_hassle_بالعربي

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The total size of NCI is 36 bits. These 36 bits are composed of gNB ID and Cell ID, broadcasting NR cell ID within SIB # 1.
GNB ID can be configured to be used between 22 bits and 32 bits, with 14 and 4 bits reserved for CI, respectively
When gNB Id is assigned 22 bits, the total gNB Id is 2 ^ 22=4194305, ranging from 0 to 4194304
NCI（NR Cell Identity）：gNB ID + CI

  1. Length: 36bit
  2. Range: 0 to 68719476735
    gNB ID
  3. Maximum length 32bit, range: 0~(2 ^ 32-1) (4294967295)
  4. Minimum length 22 bits, range: 0~(2 ^ 22-1) (4194303)
    CI：cell ID
  5. Maximum length 14 bits, range: 0~(2 ^ 14-1) (16383)
  6. Minimum length of 4 digits, range: 0~(2 ^ 4-1) (15)
    NCI calculation
    NCI = gNB_ ID * 2^(36-gNB_ID_length) + CI
    Example: gNB_ ID_ When the length is 24 bits, the CI length is 12 bits, NCI=gNBID * (2 ^ 12)+CI=gNBID * 4096+CI. Because CI occupies the 12th place, there are a total of 4096 communities
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Any way to know if the gnodebid is 22 or 32 bits?

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It is a network parameter and must be configured in commissioning proccess.