function [tx_signal, inf_bits, tx_bits] = transmitter(sim_options)
% Generates transmitted signal for one packet.

global sim_consts;
global preamble;

% Generate the information bits
% 產(chǎn)生發(fā)送信息序列
inf_bits = round(rand(1, sim_options.PacketLength));

% LDPC encoding
% LDPC編碼
tx_bits = tx_ldpc_encode(inf_bits);

% Generate number bits that is an integer multiple of OFDM symbols
% 在發(fā)送序列后面進(jìn)行填補(bǔ)，使之剛好為OFDM符號(hào)的整數(shù)倍
rdy_to_mod_bits = tx_make_int_num_ofdm_syms(tx_bits, sim_options);

% Modulate
% 調(diào)制
mod_syms = tx_modulate(rdy_to_mod_bits, sim_options.Modulation);

% Add pilot symbols
% 插入導(dǎo)引符號(hào)
mod_ofdm_syms = tx_add_pilot_syms(mod_syms, sim_options);

% Tx symbols to time domain
% 發(fā)送符號(hào)由頻域轉(zhuǎn)到時(shí)域
time_syms = tx_freqd_to_timed(mod_ofdm_syms);

% Add cyclic prefix
% 插入循環(huán)前綴
time_signal = tx_add_cyclic_prefix(time_syms);

% Concatenate preamble and data part and normalize the average signal power to 1
% 連接前導(dǎo)和數(shù)據(jù)塊并歸一化平均信號(hào)功率
tx_signal = [preamble time_signal]*sqrt(64);