function [src_data, mod_sig] = coded_mod(code_rate, m, info_sym_num, tail_sym_num, output, to_state)

% sqwang's source code, used for academic research, not commerce.
to_state = to_state + 1;     % Add 1 for matlab index convenience 

sym_num = info_sym_num + tail_sym_num;
input_sym_set_size = 2 ^ (code_rate(1)/code_rate(2) * log2(m));

src_data = randint(info_sym_num, 1, input_sym_set_size, 123);

code_sym = zeros(sym_num, 1);
code_sym(1 : info_sym_num) = src_data;
code_sym = code_sym + 1;      % Add 1 for matlab index convenience

coded_sym = zeros(sym_num, 1);
state = 1;
for i = 1 : sym_num
    coded_sym(i) = output(state, code_sym(i));
    state = to_state(state, code_sym(i));
end

mod_sig = exp(j * pi/4 * coded_sym);