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Broadcast channel



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.

codeblk = lteBCH(trblk,outlen,cellrefp) returns the vector rate-matched to the output length outlen. The argument cellrefp controls the CRC port mask.


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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 = 1×2

        1920           1

Input Arguments

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eNodeB cell-wide settings, specified as a structure containing 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

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 length, specified as a numeric scalar.

Data Types: double

Number of cell-specific reference signal (CRS) antenna ports, specified as 0, 1, 2, or 4. To turn the CRC port mask off, set cellrefp to 0.

Output Arguments

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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. “Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network. URL:

Version History

Introduced in R2014a