Files
imdd_silas/Functions/EQ_structures/ml_mlse.m
2025-11-14 11:45:13 +01:00

141 lines
4.7 KiB
Matlab

function [ml_mlse_results] = ml_mlse(eq_, M, rx_signal, tx_symbols, tx_bits, options)
%
%
% Inputs:
% eq_ - Equalizer object
% M - Modulation order
% rx_signal - Received signal
% tx_symbols - Transmitted symbols
% tx_bits - Transmitted bits
% options - Optional parameters
%
% Outputs:
% ffe_results - Results from FFE processing
arguments
eq_
M
rx_signal
tx_symbols
tx_bits
options.precode_mode db_mode
options.eth_style_symbol_mapping = 0;
options.postFFE = [];
end
%% Process signals through equalizer
[eq_signal_hd,y_ref] = eq_.process(rx_signal,tx_symbols);
%% Calculate BER based on precoding mode
[bits, errors, ber, error_pos, errors_precoded, ber_precoded] = calculateBER(eq_signal_hd, tx_symbols, tx_bits, options.precode_mode, M, options.eth_style_symbol_mapping);
% Create FFE results structure
ml_mlse_results = struct();
try
eq_.e = [];
eq_.e2 = [];
eq_.e3 = [];
eq_.b = [];
eq_.b2 = [];
eq_.b3 = [];
end
ml_mlse_results.config = Equalizerstruct();
eq_small = strip_eq(eq_, 10);
json_str = jsonencode(eq_small);
ml_mlse_results.config.eq = jsonencode(eq_);
ml_mlse_results.config.equalizer_structure = int32(equalizer_structure.ml_mlse);
ml_mlse_results.config.comment = 'function: ML-based MLSE';
ml_mlse_results.metrics = Metricstruct;
% ml_mlse_results.metrics.result_id = NaN;
% ml_mlse_results.metrics.run_id = NaN;
% ml_mlse_results.metrics.eqParam_id = NaN;
ml_mlse_results.metrics.date_of_processing = datetime('now');
ml_mlse_results.metrics.BER = ber;
ml_mlse_results.metrics.numBits = bits;
ml_mlse_results.metrics.numBitErr = errors;
ml_mlse_results.metrics.BER_precoded = ber_precoded;
ml_mlse_results.metrics.numBitErr_precoded = errors_precoded;
% ml_mlse_results.metrics.SNR = NaN;
% ml_mlse_results.metrics.SNR_level = NaN;
% ml_mlse_results.metrics.STD = NaN;
% ml_mlse_results.metrics.STD_level = NaN;
% ml_mlse_results.metrics.STDrx = NaN;
% ml_mlse_results.metrics.STDrx_level = NaN;
% ml_mlse_results.metrics.GMI = NaN;
% ml_mlse_results.metrics.AIR = NaN;
% ml_mlse_results.metrics.EVM = NaN;
% ml_mlse_results.metrics.EVM_level = NaN;
% ml_mlse_results.metrics.Alpha = NaN;
end
%% Helper Functions
function [bits, errors, ber, error_pos, errors_precoded, ber_precoded] = calculateBER(eq_signal_hd, tx_symbols, tx_bits, precode_mode, M, eth_style)
% Calculate BER based on precoding mode
mapper = PAMmapper(M, 0, "eth_style", eth_style);
switch precode_mode
case db_mode.no_db
% TX Data is not precoded
% A) Emulate diff precoding
eq_signal_hd_precoded = Duobinary().encode(eq_signal_hd, "M", M);
eq_signal_hd_precoded = Duobinary().decode(eq_signal_hd_precoded, "M", M);
tx_symbols_precoded = Duobinary().encode(tx_symbols);
tx_symbols_precoded = Duobinary().decode(tx_symbols_precoded);
tx_bits_precoded = mapper.demap(tx_symbols_precoded);
rx_bits = mapper.demap(eq_signal_hd_precoded);
[~, errors_precoded, ber_precoded, ~] = calc_ber(rx_bits.signal, tx_bits_precoded.signal, "skip_front", 30000, "skip_end", 150, "returnErrorLocation", 1);
% B) Just determine BER
rx_bits = mapper.demap(eq_signal_hd);
[bits, errors, ber, error_pos] = calc_ber(rx_bits.signal, tx_bits.signal, "skip_front", 30000, "skip_end", 150, "returnErrorLocation", 1);
case db_mode.db_precoded
% Data is precoded on TX side
% A) Decode at Rx if no DB targeting was applied
eq_signal_hd_decoded = Duobinary().encode(eq_signal_hd, "M", M);
eq_signal_hd_decoded = Duobinary().decode(eq_signal_hd_decoded, "M", M);
rx_bits_decoded = mapper.demap(eq_signal_hd_decoded);
[~, errors_precoded, ber_precoded, ~] = calc_ber(rx_bits_decoded.signal, tx_bits.signal, "skip_front", 30000, "skip_end", 150, "returnErrorLocation", 1);
% B) Omit the Coding by comparing with demapped TX symbol sequence
tx_bits_demapped = mapper.demap(tx_symbols);
rx_bits = mapper.demap(eq_signal_hd);
[bits, errors, ber, error_pos] = calc_ber(rx_bits.signal, tx_bits_demapped.signal, "skip_front", 30000, "skip_end", 150, "returnErrorLocation", 1);
end
end
function eq_out = strip_eq(eq_, max_elems)
% strip_eq removes all large fields from the ML_MLSE object
% eq_out = strip_eq(eq_, max_elems)
% max_elems ... maximum number of elements to keep (default = 10)
if nargin < 2
max_elems = 10; % default threshold
end
props = properties(eq_);
for i = 1:numel(props)
val = eq_.(props{i});
if ~isempty(val)
% Count total number of elements
if numel(val) > max_elems
eq_.(props{i}) = [];
end
end
end
eq_out = eq_;
end