Use flat buffer for txdataF in gNB L1
This MR changes txdataF buffer format to hold freq domain data starting from
PRB0 instead of circular buffer that starts from PRB N/2. The motive is to
simplify RE mapping function in L1 and copying data to xran lib.
So far txdataF buffer has DC RE as the first element. This was prefered
most likely to avoid memcpy before iFFT but comes with a small
complexity in RE mapping functions.
Instead, we use a flat buffer that holds freq domain data starting from
first negative SC. After resource mapping is done on all channels, each
OFDM symbol is shifted before iFFT so that the buffer start with DC RE.
This reduces complexity in mapping functions and later on when passing
beam IDs to 7.2 split RU especially when a beam is associated to
interleaved RB and/or REs.
There is already a memcpy in place to copy txdataF from gNB stuct to RU
struct. So this change does not introduce new memcpy.
Rename nr_slot_fep_ul to nr_symbol_fep_ul to relfect its function
Simplify logic so that the function does not require RU context and
the implementation is not dependent on the implementation of RU buffer management.
This makes the function easier to understand and moves the responsibility
to set the correct buffer offset on the caller.
- Introduce signal energy and noise variance functions
- Combine rotation and OFDM modulation RX as a function
- Harmonize the use of number of antennas across the code
- Rename nr_ue_pusch_common_procedures() to nr_tx_rotation_and_ofdm_mod() to decribe the functionality better
1. Removed function pointers for functions get_samples_per_slot(),
get_samples_slot_timestamp() and get_slot_from_timestamp() as it does
not offer any advantage. The functions are now called directly from
everywhere.
2. Optimized these functions by removing loops where ever possible.
1.Create new funtion nr_symbol_fep() to do OFDM demod of one symbol on
all antennas. This is called by nr_slot_fep() for now. In the
upcoming MR, this function will be called directly after reading
each OFDM symbol from the radio.
2.Removed redundant memory alignment. DFT function performs memory
alignment if the input memory is not aligned.
Alignment of temporary IDFT buffer was changed to 64 bytes. This is in preparation
for possible use of different IDFT implementation which could use AVX-512, requiring
64-byte alignment.
It seems that the cyclic prefix is in most cases a multiple of 512 samples.
This means that in most cases the idft output pointer is already aligned and
there is no need to perform an extra memcpy. This saves the memcpy time in
most cyclic prefix insertion cases.
Simplify logs in gNB&UE
- reduce the amount of printf() that outputs useless info
- in MAC, PHY, NGAP, RRC, mark some "important" UE events with LOG_A for
better visibility -> can put log_config.global_log_level analysis to
only see important stuff
- in RRC, use some macro to consistently print logs
- track the cellID of a UE in RRC
This commit removes many logs that just show memory addresses, indices,
etc., which, I presume, do not mean anything to the "average user" and
developers alike.
Jaroslava Fiedlerova