Bug-fix in Up-link with respect to PUSCH RE calculation when PTRS is enabled.
Problem STATEMENT: - When enabling PTRS flag in ulsim, there are multiple scrambling and decoding errors are observed even with high SNR values SNR 60dB errors_scrambling 5546/13800 Channel BLER 1.000000e+00, Channel BER 4.018841e-01 ANALYSIS: - While extracting PTRS RE's, the PUSCH RE count was not updated accordingly for PTRS symbols. - This results in 0 value LLR's on same positions which cause offset issue in later processing. IMPLEMENTATION: * nr_ulsch_demodulation.c - In case of PTRS symbol, respective total number of PTRS RE's are subtracted from available PUSCH RE's in each PUSCH Symbol processing. TESTING * ulsim.c - PTRS are enabled for testing and are not enabled by default by this commit. - Available bit count is adjusted if PTRS is enabled. VERIFICATION - Total Scrambling errors after gNb processing shall be only 250 bits (in K=2) which were replaced with PTRS at UE side while transmission. SNR 60.000000 errors_scrambling 250/13800 Channel BLER 0.000000e+00, Channel BER 1.811594e-02 - After adjusting available bits in ulsim.c for error calculation SNR 60.000000: n_errors errors_scrambling 0/13550 Channel BLER 0.000000e+00, Channel BER 0.000000e+00 EXTRA - Removed white-spaces from all above mentioned files - Added Global/vim tags to .gitignore file
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