function time_signal = tx_add_cyclic_prefix(time_syms)

num_symbols = size(time_syms, 2)/64;
time_signal = zeros(1, num_symbols*80);

symbols = reshape(time_syms, 64, num_symbols);
tmp_syms = [symbols(49:64,:); symbols];

%符號.'表示單純的轉置（非共軛轉置）
time_signal = tmp_syms(:).';