Broadcast channel


  • codeblk = lteBCH(enb,trblk)



codeblk = lteBCH(enb,trblk) returns a vector of BCH transport channel coded bits. The encoding process includes CRC calculation and attachment, convolutional encoding, and rate matching as defined in TS 36.212 [1], Section 5.3.1.

The rate matching internal to the coding results in many repetitions of the coded block. This repetition is deliberate so that part of a received block can be successfully decoded in isolation. Typically, the receiver can recover the BCH bits from the reception of just one frame (¼ of the transmitted block), rather than waiting 40 ms (four frames) for the full block to be received.


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Encode BCH Information Bits

Generate the BCH coded vector of length 1920, corresponding to normal cyclic prefix.

enb = struct('CellRefP',1,'CyclicPrefix','Normal');
bchCoded = lteBCH(enb,ones(24,1));
bchCodedSize = size(bchCoded)
bchCodedSize =

        1920           1

Input Arguments

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enb — eNodeB cell-wide settingsscalar structure

eNodeB cell-wide settings, specified as a structure that can contain these parameter fields.

Parameter FieldRequired or OptionalValuesDescription

1, 2, 4

Number of cell-specific reference signal (CRS) antenna ports


'Normal' (default), 'Extended'

Cyclic prefix length

trblk — Transport blocknumeric vector

Transport block, specified as a numeric vector of length 24 bits. This argument represents the transport block delivered to the BCH every 40 ms.

Output Arguments

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codeblk — BCH transport channel coded bitsnumeric column vector

BCH transport channel coded bits, returned as an integer column vector with 1920 bits for normal cyclic prefix or 1728 bits for extended cyclic prefix.

Data Types: int8


[1] 3GPP TS 36.212. "Multiplexing and channel coding." 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA). URL:

Introduced in R2014a

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