基于GMSK差分解調(diào)仿真（3）

既然講到了2bit差分解調(diào)，那就展示一下仿真程序吧！本課題的內(nèi)容非常多，希望大家能夠在學(xué)習(xí)程序的同時結(jié)合相關(guān)資料，這樣有助于理解！后面文章也會上傳資料到網(wǎng)盤，現(xiàn)在還在整理中，整理完成后就在文章中給出下載鏈接！這個系列的文章已經(jīng)寫了三篇，本人明顯感覺精力不濟，需要休息一下，后續(xù)再寫涉及到仿真程序的文章！

不斷修訂程序！

力求深入淺出！

當然也在不斷的增加注釋！

%%****************** 程序主體 ***********************%%

format long;

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

%%%%%%%%%% 仿真參數(shù)部分 %%%%%%%%%

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

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

sr = 16000; % Symbol rate

frame_len = 3; % subframe number，實際只測試第2幀

br = sr; % Bit rate

frame_sumbitlen = 384 ; % 每時隙總bit數(shù)

slot_FB_BKN2_bitlen = 156; % 時隙FB編碼后的載荷bit數(shù)

IPOINT = 4;

% Number of oversamples after AGC

lp_bp = 0.25; % 低通濾波器帶寬

lp1_bp = 0.5;

% 仿真結(jié)果表明在有頻偏的情況下：0.25時效果最好 ！

% 這比8倍采樣時設(shè)置的0.06稍大，從解調(diào)的誤碼性能來說差異不大，但譯碼性能存在差異。

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 *****************************

%%% 信號源

% 發(fā)送數(shù)據(jù)

data_cpu = randi([0 1],frame_len,slot_FB_BKN2_bitlen*2); % 來自CPU的數(shù)據(jù)

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

%%%%%%%%%%%%%%%% 調(diào)制器部分 %%%%%%%%%%%%%%%%

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

%%%%%% 調(diào)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

%%% 訓(xùn)練序列

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

%%% 數(shù)據(jù)組BBK

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

% 組幀規(guī)則

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

%%% 信號組幀

information = infloop;

%%% 差分編碼

% 和1bit差分解調(diào)的差異之處?。。?/p>

編輯：jq