ltePCFICHIndices

PCFICH resource element indices

Syntax

ind = ltePCFICHIndices(enb)

ind = ltePCFICHIndices(enb,opts)

Description

ind = ltePCFICHIndices(enb) returns the 16-by-CellRefP matrix of subframe resource element (RE) indices for the physical control format indicator channel (PCFICH), given the enb input structure. By default, the indices are returned in 1-based linear indexing form that directly indexes elements of a 3-D array representing the subframe resource grid for CellRefP antenna ports. Each column of ind contains per-antenna indices for 16 resource elements in one of the CellRefP array planes. The rows are ordered as the PCFICH modulation symbols should be mapped. The indices can also be returned in a number of alternative indexing formats.

The PCFICH is always transmitted on 16 resource elements, or 4 resource element groups (REG), in the first OFDM symbol of a subframe however their locations depend on the NCellID and NDLRB parameters.

ind = ltePCFICHIndices(enb,opts) formats the returned indices using options specified by opts.

Examples

Generate PCFICH RE Indices

This example generates physical CFI channel (PCFICH) resource element (RE) indices for two different physical layer cell identity values.

To show the effects of the physical layer cell identity, NCellID, on the indices, first set it to 0. Generate and display the PCFICH indices.

enb.NDLRB = 50;
enb.NCellID = 0;
enb.CyclicPrefix = 'Normal';
enb.CellRefP = 1;
ind = ltePCFICHIndices(enb,{'0based','reg'});
disp(ind)

     0
   150
   300
   450

Next, set the physical layer cell identity, NCellID, to 1. Regenerate and display the PCFICH indices.

enb.NCellID = 1;
ind = ltePCFICHIndices(enb,{'0based','reg'});
disp(ind)

     6
   156
   306
   456

Input Arguments

enb — eNodeB cell-wide settings

scalar structure

eNodeB cell-wide settings, specified as a structure containing these parameter fields:

Parameter Field	Required or Optional	Values	Description
NDLRB	Required	Scalar integer from 6 to 110	Number of downlink resource blocks ($$N_{\text{RB}}^{\text{DL}}$$)
NCellID	Required	Integer from 0 to 503	Physical layer cell identity
CyclicPrefix	Optional	'Normal' (default), 'Extended'	Cyclic prefix length
CellRefP	Optional	1 (default), 2, 4	Number of cell-specific reference signal (CRS) antenna ports

opts — Output format, base, and unit of generated indices

character vector | string scalar | cell array of character vectors | string array

Output format, base, and unit of generated indices, specified as one of these forms.

• 'format base unit'

• "format base unit"

• {'format','base','unit'}

• ["format","base","unit"]

Where format, base, and unit are defined in this table.

Option	Values	Description
format	'ind' (default), 'sub'	Output format of generated indices To return the indices as a column vector, specify this option as 'ind'. To return the indices as an NRE-by-3 matrix, where NRE is the number of REs, specify this option as 'sub'. Each row of the matrix contains the subcarrier, symbol, and antenna port as its first, second, and third element, respectively.
base	'1based' (default), '0based'	Index base To generate indices whose first value is 1, specify this option as '1based'. To generate indices whose first value is 0, specify this option as '0based'.
unit	're' (default), 'reg'	Unit of returned indices To indicate that the returned values correspond to individual resource elements (REs), specify this option as 're'. To indicate that the returned values correspond to resource element groups (REGs), specify this option as 'reg'.

Example: 'ind 0based reg', "ind 0based reg", {'ind','0based','reg'}, and ["ind","0based","reg"] specify the same output options.

Data Types: char | string | cell

Output Arguments

ind — Subframe PCFICH RE indices

numeric matrix

Subframe PCFICH RE indices, returned as a numeric matrix of size 16-by-CellRefP. Each column of ind contains per-antenna indices for 16 resource elements in one of the CellRefP array planes. The rows are ordered as the PCFICH modulation symbols should be mapped.

Version History

Introduced in R2014a