add nrPDSCHDecode()

py3gpp/__init__.py

@@ -35,6 +35,7 @@
 from .nrPDSCHDMRSIndices import nrPDSCHDMRSIndices
 from .nrPDSCHDMRS import nrPDSCHDMRS
 from .nrPDSCH import nrPDSCH
+from .nrPDSCHDecode import nrPDSCHDecode
 
 from .configs.nrCarrierConfig import nrCarrierConfig
 from .configs.nrNumerologyConfig import nrNumerologyConfig

py3gpp/nrPDSCHDecode.py

@@ -0,0 +1,30 @@
+import numpy as np
+from py3gpp.nrSymbolDemodulate import nrSymbolDemodulate
+from py3gpp.nrPRBS import nrPRBS
+
+def nrPDSCHDecode(sym, mod, nid, rnti):
+    descrambled_bits = []
+    n_layers = sym.shape[0]
+    if n_layers != 1:
+        raise NotImplementedError('not ready yet')
+
+    for i in range (n_layers):
+        demod_sym = nrSymbolDemodulate(sym[i], mod[i])
+        cinit = (rnti * 2**15) + (i * 2**14) + nid
+        prbs_bits = nrPRBS(cinit, len(demod_sym))
+        descrambled_bits.append(np.multiply(demod_sym, (-prbs_bits*2 + 1)))
+        descrambled_bits = np.array(descrambled_bits)
+    return descrambled_bits
+
+
+
+if __name__ == '__main__':
+    modulation = ['16QAM']
+    nlayers = 1
+    ncellid = 42
+    rnti = 6143
+    data = np.random.randint(0, 2, size=(1, 8000))
+    import py3gpp
+    txsym = py3gpp.nrPDSCH(data, modulation, nlayers, ncellid, rnti)
+    rxbits = nrPDSCHDecode(txsym, modulation, ncellid, rnti)
+    assert np.array_equal(data, np.round(rxbits<0).astype(int))

tests/test_nrPDSCHDecode.py

@@ -0,0 +1,16 @@
+import numpy as np
+import pytest
+
+from py3gpp.nrPDSCH import nrPDSCH
+from py3gpp.nrPDSCHDecode import nrPDSCHDecode
+
+@pytest.mark.parametrize('ncellid', [0, 1, 2, 3])
+@pytest.mark.parametrize('modulation', ['16QAM', 'QPSK', 'BPSK'])
+def test_run_nr_pdsch_combined(ncellid, modulation):
+    modulation = [modulation]
+    nlayers = 1
+    rnti = 6143
+    data = np.random.randint(0, 2, size=(1, 8000))
+    txsym = nrPDSCH(data, modulation, nlayers, ncellid, rnti)
+    rxbits = nrPDSCHDecode(txsym, modulation, ncellid, rnti)
+    assert np.array_equal(data, np.round(rxbits<0).astype(int))