LTE PDCCH Calculator | LTE CCE Index Calculator

This page mentions LTE PDCCH Calculator. It calculates CCE Index based on Aggregation level or PDCCH formats. The formula used in LTE PDCCH calculator or CCE Index calculation is also mentioned.

CCE stands for Control Channel Elements. 1 CCE occupies 36 REs (Resource Elements) or 72 bits as it is QPSK modulated. PDCCH format 0 refers to aggregation level of 1, PDCCH format 1 refers to aggregation level of 2, PDCCH format 2 refers to aggregation level of 4 and PDCCH format 3 refers to aggregation level of 8.

➨If CCE Index is 0 and aggregation level is 4 means, it occupies CCE positions from 0 to 3.
➨If CCE index is 4 and aggregation level is 4 means, it occupies CCE positions from 4 to 7.
➨If CCE index is 0 and aggregation level is 8 means, it occupies CCE positions from 0 to 7.
and so on...

LTE PDCCH CALCULATOR EXAMPLE for CCE Index Calculation:
Input : Aggregation level (L) = 1, N_CCE = 100 , Subframe (k ) = 1,
Outputs : CCE Index = 49

Following table mentions all possible inputs and respective CCE index as output. It also mentions intermediate outputs e.g. yk and y(k-1).

LTE CCE Index Calculation formula used in LTE PDCCH Calculator

Following equations/formula are used in this LTE PDCCH Calculator for CCE Index calculation.

Where,
L = Aggregation levels viz. 1/2/4/8
N_CCE = Number of CCEs available for PDCCH channel type
m = range from 0 to (Number of PDCCH candidates-1)
i = range from 0 to (L-1)
Yk = { A * (Yk-1) } mod D
k =Subframe number
A = constant value of 39827
D = constant value of 65537

For k = 0, (Yk-1) = RNTI value of UE = Assume as 100 say

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