基于GMSK差分解调仿真（3）

既然讲到了2bit差分解调，那就展示一下仿真程序吧！本课题的内容非常多，希望大家能够在学习程序的同时结合相关资料，这样有助于理解！后面文章也会上传资料到网盘，现在还在整理中，整理完成后就在文章中给出下载链接！这个系列的文章已经写了三篇，本人明显感觉精力不济，需要休息一下，后续再写涉及到仿真程序的文章！

不断修订程序！

力求深入浅出！

当然也在不断的增加注释！

%%****************** 程序主体 ***********************%%

format long;

%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%% %%%%%%

%%%%%%%%%% 仿真参数部分 %%%%%%%%%

%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%

%******************** Preparation part *******************

sr = 16000; % Symbol rate

frame_len = 3; % subframe number，实际只测试第2帧

br = sr; % Bit rate

frame_sumbitlen = 384 ; % 每时隙总bit数

slot_FB_BKN2_bitlen = 156; % 时隙FB编码后的载荷bit数

IPOINT = 4;

% Number of oversamples after AGC

lp_bp = 0.25; % 低通滤波器带宽

lp1_bp = 0.5;

% 仿真结果表明在有频偏的情况下：0.25时效果最好 ！

% 这比8倍采样时设置的0.06稍大，从解调的误码性能来说差异不大，但译码性能存在差异。

EbNoLise = 9:16;

%******************** START CALCULATION ***************************

nloop = 1000; % Number of simulation loops

freoffset = 0; % Fixed frequency offset

frephase_idx = 0;

phaoffset = frephase_idx*pi;

fresample = IPOINT*sr;

%************************* Filter initialization **************************

tra_coef = 0.3;

%************************* Data generation *****************************

%%% 信号源

% 发送数据

data_cpu = randi([0 1],frame_len,slot_FB_BKN2_bitlen*2); % 来自CPU的数据

%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%% %%%%%%%%%%%%%

%%%%%%%%%%%%%%%% 调制器部分 %%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%% %%%%%%%%%%%%%%

%%%%%% 调制器DSP部分 %%%%%%%%%

%************************* signal frame generate *********************

% bit reverse

data_code = 2*data_cpu - 1;

%%% 同步序列

qa_NB = 2*[ 1,0,1,0,1,1,0,1,1,1 ] - 1; % 10 bit for NB

%%% 训练序列

pd_NB = 2*[ 1,1,1,0,1,1,0,1,0,1,1,0,0,1,1,0,0,0,0,0] - 1; % 20 bit for NB

len_pd_NB = 20;

%%% 同步序列

qb_NB = 2*[ 0,0,0,0,0,1,1,0,0,1 ] - 1; % 10 bit for NB

%%% 数据组BBK

BBK_NB = 2*randi([0 1],1,32) - 1;

% 组帧规则

for i = 1:frame_len

infloop((i-1)*frame_sumbitlen+1:i*frame_sumbitlen) = [qa_NB data_code(i,1:slot_FB_BKN2_bitlen) BBK_NB(1:16) pd_NB BBK_NB(17:32) data_code(i,slot_FB_BKN2_bitlen+1:end) qb_NB];

infor_loop(i,:) = infloop((i-1)*frame_sumbitlen+1:i*frame_sumbitlen);

end

%%% 信号组帧

information = infloop;

%%% 差分编码

% 和1bit差分解调的差异之处！！！

编辑：jq