【正文】 =isq。 end 擴頻部分 function [iout, qout] = spread(idata, qdata, code1) %變量含義說明 % idata 輸入序列實部 % qdata 輸入序列虛部 % iout 輸出序列實部 % qout 輸出序列虛部 % code1 擴頻碼序列 switch nargin case { 0 , 1 } error(39。)。 qdata = idata。 [hc,vc] = size(code1)。lack of spread code sequences39。 end iout = zeros(hn,vn*vc)。 for ii=1:hn iout(ii,:) = reshape(rot90(code1(ii,:),3)*idata(ii,:),1,vn*vc)。 end 信道仿真部分 實現(xiàn)高斯白噪聲代碼函數(shù) function [iout, qout] = b2(idata, qdata, attn) %各變量含義說明 % idata 輸入序列實部 % qdata 輸入序列虛部 % iout 輸出序列實部 % qout 輸出序列虛部 % attn 根據(jù)信噪比得到的信號衰減水平 v = length(idata)。 iout = zeros(h,v)。 for ii=1:h iout(ii,:) = idata + randn(1,v) * attn(ii)。 end 黃河科技學院畢業(yè)論文 第 28 頁 接收機的解擴部分函數(shù) function [iout, qout] = despread(idata, qdata, code1) %各變量含義說明 % idata 輸入序列實部 % qdata 輸入序列虛部 % iout 輸出序列實部 % qout 輸出序列虛部 % code1 擴頻碼序列 switch nargin case { 0 , 1 } error(39。)。 qdata = idata。 [hc,vc] = size(code1)。 iout = zeros(hc,vn)。 for ii=1:hc iout(ii,:) = rot90(flipud(rot90(reshape(idata(ii,:),vc,vn)))*rot90(code1(ii,:),3))。 end 接收機解調部分的函數(shù) function [demodata]=qpskdemod(idata,qdata,para,nd,ml) %各變量含義說明 % idata 輸入數(shù)據(jù)的實部 % qdata 輸入數(shù)據(jù)的虛部 % demodata 解調后的數(shù)據(jù) % para 并行的信道數(shù) % nd 輸入數(shù)據(jù)個數(shù) % ml 調制階數(shù) demodata=zeros(para,ml*nd)。 demodata((1:para),(2:ml:ml*nd))=qdata((1:para),(1:nd))=0。 nod2 = user * nd * ml。 nod = nod + nod2。%d\t%e\n39。 end %數(shù)據(jù)文件 ber = noe / nod。%d\t%d\t%d\t%e\n39。 fid = fopen(39。,39。)。%d\t%e\t%f\t%f\t\n39。 fclose(fid)。 end %性能仿真圖 figure semilogy(SNR,err_rate_final,39。)。信噪比 /dB39。誤碼率 39。 clc sr = 。 % 調制階數(shù) br = sr * ml。 % 符號數(shù) SNR=5:1:10。 % 用戶數(shù) stage = 3。 % 第一個線性移位寄存器的系數(shù) 黃河科技學院畢業(yè)論文 第 31 頁 disp(39。)。 code = code * 2 1。 %******************仿真運算開始 ****************** nloop = 1000。 nod = 0。 [ich, qch] = qpskmod(data,user,nd,ml)。 % 擴頻 ich2 = ich1。 %******************接收機 ****************** [ich3,qch3] = b2(ich2,qch2,attn)。 ich4 = ich3(:,sampl:IPOINT:IPOINT*nd*clen+sampl1)。 [ich5 qch5] = despread(ich4,qch4,code)。 % QPSK 解調 %******************誤碼率分析 ****************** noe2 = sum(sum(abs(datademodata)))。 noe = noe + noe2。 %******************數(shù)據(jù)文件 ****************** ber = noe / nod。%d\t%d\t%d\t%e\n39。 fid = fopen(39。,39。)。%d\t%e\t%f\t%f\t\n39。 fclose(fid)。 %******************性能仿真圖 ****************** figure semilogy(SNR,err_rate_final,39。)。信噪比 /dB39。誤碼率 39。end39。 黃河科技學院畢業(yè)論文 第 33 頁 a 您好，為你提供優(yōu)秀的畢業(yè)論文參考資料，請您刪除以下內容， O(∩_∩)O 謝謝?。?！A national survey was recently launched to evaluate the eye health of Chinese children andteenager June 6, China39。s digitized society, will also be attached on the report.Myopia is not only a disease that makes people see things blurrily, but also leads to severeplications, such as glaua (increased pressure within the eyeball), and can causeblindness, said Zhou Yuehua, an established eye care specialist with Beijing TongrenHospital.It is very important for parents and children to know about the risk and care for their eyes.There are about 450 million myopia patients in China. Among Chinese myopia patients,30million are severe patients, according to ZhouThe prevalence of myopia among high school and college students is more than 70 percent,and the situation is continuously worsening, he a Zhu, director with the China Youth Development Service Center, said long hours ofstudy, lack of exercise, especially outdoor activities, and attachment to electronic screen aresome of the top reasons behind the widespread myopia problems, and the increase ofyounger patients, although China has made great progress in improving the hardwarefacilities and lighting conditions in schools.He said he hopes the survey will alert people on the threatening situation, and also helpmedical experts to better guideline parents and children39。s work can be a way to unwind. It is true for He Wenjun, whose workplace is right near the forest park. She discovered her athletic aptitude at the age of seven, when she began playing tennis. Then she turned to jogging, and she has persevered with it for 10 years. I e to jog almost every day after work, whenever I have time. I think jogging is good for my health. And for me, a girl, it helps me to achieve to eternal goal, to keep slim, He said. He says she prefers jogging alone, so she can focus better. She loves jogging, even during Beijing39。ll hold off jogging for a while. But if I really want to get away from work, I39。s health. Poor technique harms the muscles and skeleton, and can cause secondary injures. And, jogging in a bad environment can cause circulation problems, said Lu Zhiyong, attending doctor, Sports Hospital, General Admin. of . Lu has some tips for joggers, and those who are thinking of taking it says people sh ould first evaluate their physical condition, to decide the amount and type of exercise, and jogging in the open air is better running on a treadmill. Conrad Macao will run special programs for the entire month of October this year to support the Hong Kong Cancer Fund39。t conducive to raising a child. She planned to have children once she had achieved career success so she could provide a stable environment for her baby. After 10 years, Xiao felt the time was right, and she tried to conceive for about six months, but was unable to bee pregnant. I conducted prehensive physical checkups. The results suggested that Xi