Physical Sidelink Broadcast Channel (PSBCH)

PSBCH Transmitter

E        = 1386
cellID   = 414
psbchObj = PSBCH(E,cellID)
inputBits   = np.random.randint(2,size=(1,40))
SSSBPayload = psbchObj(inputBits,verbose = False)

class toolkit5G.PhysicalChannels.PSBCH(E, cellID)[source]

Physical Sidelink Broadcast Channel (SS/PBCH) Blocks are used during the cell search procedure, i.e. UE search for Synchronisation Signals when scanning for a cell to camp on

Parameters:

E (int) – Number of Target Bits expected at the end of rate matching.
cellID (int) – Defines the cell-ID \(\in \{0, 1, \dots, 1007\}\).

Note

The value of E is 1386 when number of Symbols allocated for SSB is 11 and E = 1782 when the number of symbols allocated for SSB is 13

Input:

inputBits (np.ndarray) – SL SSB payload bits It must be a 2-dimensional array
verbose (bool) – Flag to indicate whether verbal explanation of PSBCH transmitter is required

Output:

[inputBits.shape[0],E/2]: np.ndarray – Array containing the SSB payload

Attributes:

crcEncoder (object)
bitInterleaver (object)
subBlockInterleaver (object)
channelInterleaver (object)
scrambler (object)
mapper (object)

K              = 40
cellID         = 414
symbolDemapper = "app"
psbchDeObj     = PSBCHDecoder(K,cellID,symbolDemapper)
intvar         = np.random.choice([-np.sqrt(1/2)-1j*np.sqrt(1/2),-np.sqrt(1/2)+1j*np.sqrt(1/2),np.sqrt(1/2)-1j*np.sqrt(1/2),np.sqrt(1/2)+1j*np.sqrt(1/2)],size = (2,1))
inputSymbols   = intvar@np.ones(shape = (1,int(E/2)))
snr            = 1000
polarDecoder   = "SC"
decodedBits    = psbchDeObj(inputSymbols,snr,polarDecoder)

class toolkit5G.PhysicalChannels.PSBCHDecoder(K, cellID, symbolDemapper)[source]

Parameters:

K (int) – Defines the size of SL-SSB in terms of bits.
cellID (int) – Defines the cell-ID \(\in \{0, 1, \dots, 1007\}\).
symbolDemapper (str) – Defines the technique used for symbol demapping can take either “app” or “maxlog”

Input:

inputSymbols (np.ndarray) – It is a numpy array of size [:,(E/2] it denoted the received SL-SSB that is to be decoded
snr (int or float or np.number) – Defines the Signal to Noise Ratio in linear scale
polarDecoder (str) – Defines the decoding technique. It is expected to possess one string among the following `{“SC”, “SCL”, “SCL8”, “SCL32”, “hybSCL”, “BP”}.

Output:

[ (,K]: np.array) – The decoded SL-SSB bits

Attributes:

demapper (object)
descrambler (object)
channelDeInterleaver (object)
subBlockDeInterleaver (object)
inputDeInterleaver (object)
crcDecoder (object)

PSBCH COMPONENTS

References:: [3GPPTS38211psbch]
(3GPP TS 38.211 version 17.1.0 Release 17) 5G;NR;Physical channels and modulation.