Sidelink broadcast channel decoding
[trblkout,crcerr] = lteSLBCHDecode(ue,softbits)
a 40-by-1 column vector of information bits and the cyclic redundancy
check (CRC) result for the specified UE settings structure and recovered
The SL-BCH decoder performs the inverse of the sidelink broadcast
channel processing performed by
and as defined in TS 36.212 ,
Section 5.4.1. The decoding operation includes PUSCH deinterleaving,
rate recovery, tail-biting convolutional decoding, and CRC decoding.
Decode a sidelink broadcast channel (SL-BCH) codeword.
Create a UE-specific configuration structure with normal cyclic prefix.
ue.CyclicPrefixSL = 'Normal';
Generate an SL-BCH codeword by using an MIB-SL transport block of all ones. Display the CRC result.
trblk = ones(40,1); slbchCoded = lteSLBCH(ue,trblk); [slbchDecoded,err] = lteSLBCHDecode(ue,slbchCoded); err
err = uint32 0
The CRC result indicates no error.
isequal reconfirms the decoded output matches the input transport block.
ans = logical 1
ue— User equipment settings
User equipment settings, specified as a parameter structure containing these fields:
softbits— Log-likelihood ratio soft bits
Log-likelihood ratio (LLR) soft bits, specified as a vector. Nominally,
softbits contains 1152 bits for normal cyclic
prefix, 864 bits extended cyclic prefix, or 1008 bits for V2X. These lengths
match the bit capacity of the PSBCH, ignoring the SC-FDMA guard symbol.
Because PSBCH uses a low code rate and the decoder can successfully
decode much shorter blocks than the entire coded block, input
be any length.
trblkout— Transport block
Transport block, returned as a 40-by-1 column bit vector representing the MIB-SL information bits sent by a transmitting UE on the SL-BCH transport channel. The MIB-SL information bits are decoded from the soft log-likelihood (LLR) codeword data.
crcerr— CRC error status
CRC error status, returned as 0 for a pass and 1 for a block error.
 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: http://www.3gpp.org.