LTE ECGI and ECI Calculator: Understanding Cell Identifiers

This page provides information and calculators for LTE ECGI (E-UTRAN Cell Global Identifier) and LTE ECI (E-UTRAN Cell Identifier). We’ll cover the formulas and calculations involved in determining these crucial identifiers.

What are ECI and ECGI?

• ECI (E-UTRAN Cell Identifier): This identifier uniquely identifies a cell within a Public Land Mobile Network (PLMN).
• ECGI (E-UTRAN Cell Global Identifier): This identifier uniquely identifies a cell globally.

LTE ECGI and ECI Calculator/Calculation

Here are a couple of examples to illustrate how the ECI and ECGI are calculated.

EXAMPLE #1:

• Inputs:
  • eNB ID = 0xFFFFF (20 bits)
  • Cell ID = 0xAA (8 bits)
  • PLMN ID (MCC=0xBBB, MNC=0xCCC) = 0xBBBCCC (24 bits)
• Outputs:
  • ECI = FFFFFAA
  • ECGI = BBBCCCFFFFFAA (52 bits)

Example #2:

• Inputs:
  • eNB ID = 0x23456
  • Cell ID = 0x11
  • PLMN ID = 0xBBBCCC
• Outputs:
  • ECI = 2345611
  • ECGI = BBBCCC2345611

Steps to Calculate ECI and ECGI

Here’s a breakdown of the steps involved in calculating ECI and ECGI:

1. Step-1: Shift the eNB ID to the left by 8 bits. For example, if eNB ID = 0xFFFFF, after shifting, it becomes 0xFFFFF00.
2. Step-2: Perform a bitwise OR operation between the shifted eNB ID and the Cell ID. Let’s say Cell ID = 0xAA.
3. Step-3: The result of the bitwise OR from Step-2 is the ECI value. In our example, after the OR operation, ECI = 0xFFFFFAA. (This will be of 28 bit in size).
4. Step-4: Shift the PLMN ID to the left by 28 bits. If PLMN ID = 0xBBBCCC (where MCC = 0xBBB and MNC = 0xCCC), after shifting, it becomes 0xBBBCCC0000000.
5. Step-5: Perform a bitwise OR operation between the shifted PLMN ID and the ECI value obtained in Step-3. The result is the ECGI.

In our example, we get an ECGI value of 0xBBBCCCFFFFFAA. The ECGI is a maximum of 52 bits in size.

Note: The values used here are in hexadecimal format for clarity. If you have decimal values for eNB ID, Cell ID, or PLMN ID, you’ll need to convert them to hexadecimal before performing these calculations.

Formula/Equations for LTE ECGI and ECI Calculation

The following formula are used in the LTE ECGI and ECI calculation.