LDPC

pip install sim-ldpc

python -m pytest

python -m pytest --cov-report=html

python -m pytest  -n auto --cov-report=html

mypy --strict --config-file .mypy.ini.

Included modules

Basic Example

importnumpyasnpfrombitstringimportBitArray,Bitsfromldpc.decoderimportDecoderWiFi,bsc_llrfromldpc.encoderimportEncoderWiFifromldpc.wifi_spec_codesimportWiFiSpecCodefromldpc.utilsimportQCFile# create information bearing bitsrng=np.random.default_rng()info_bits=np.array(Bits(bytes=rng.bytes(41))[:648//2],dtype=np.int_)# create encoder with frame of 648 bits, and rate 1/2. Possible rates and frame sizes are per the ieee802.11n spec.enc=EncoderWiFi(WiFiSpecCode.N648_R12)# encode bitsencoded=enc.encode(info_bits)# verify validity of codewordh=enc.hnp.dot(h,np.array(encoded))%2# creates an all zero vector as required.# create a decoder which assumes a probability of p=0.05 for bit flips by the channel# allow up to 20 iterations for the bp decoder.p=0.05decoder=DecoderWiFi(spec=WiFiSpecCode.N648_R12,max_iter=20,channel_model=bsc_llr(p=p))# create a corrupted version of encoded codeword with error rate pcorrupted=BitArray(encoded)no_errors=int(len(corrupted)*p)error_idx=rng.choice(len(corrupted),size=no_errors,replace=False)foridxinerror_idx:corrupted[idx]=notcorrupted[idx]decoded,llr,decode_success,num_of_iterations,syndrome,vnode_validity=decoder.decode(corrupted)# Verify correct decodingprint(Bits(decoded)==Bits(encoded))# trueinfo=decoder.info_bits(decoded)# a decoder can also be instantiated without a channel model, in which case llr is expected to be sent for decoding instead of# hard channel outputs.channel=bsc_llr(p=p)channel_llr=channel(np.array(corrupted,dtype=np.int_))decoder=DecoderWiFi(spec=WiFiSpecCode.N648_R12,max_iter=20)decoded,llr2,decode_success,num_of_iterations,syndrome,vnode_validity=decoder.decode(channel_llr)print(Bits(decoded)==Bits(encoded))# trueinfo=decoder.info_bits(decoded)

python3 -m venv~/.virtualenv/LDPC_env

source~/.virtualenv/LDPC_env/bin/activatepip install sim-ldpcpip install notebook

~/.virtualenv/LDPC_env/bin/jupyter-notebook

Sources