求救，该了很久改不出来呀！拜托了！

xianjuan

谢谢各位了，请帮忙哈！急需，但是改了很久改不出来，在调制那里有错，而且高斯噪声加不上呀！拜托了！

1. f_data=1;
   
2. f_chip=11;
   
3. fc=220;
   
4. fs=3*fc;
   
5. N=fs/f_chip;
   
6. data_length=5000;
   
7. M=2;
   
8. num_of_user=4;
   
9. matches=0;
   
10. errors=0;
    
11. count=1;
    
12. SNRpbit=0;
    
13. SNR=SNRpbit;
    
14. 
    
15. rand('state',sum(100*colock));
    
16. randn('state',sum(100*colock));
    
17. numplot=100;
    
18. msg_unsprd=randsrc(data_length,num_of_user,[0:M-1]);
    
19. PN_seq=(11,num_of_user,[0:1]);
    
20. 
    
21. for s=1:num_of_user
    
22.     j=1;
    
23.     for i=1:data_length
    
24.        for k=j:j+f_chip-1
    
25.        mdg_coded(s,k)=msg_unsprd(i,s);
    
26.        end;
    
27.     msg_spread(s,[j:(j+f_chip-1)])=xor(msg_coded(s,[j:(j+f_chip-1)])',PN_seq([1:f_chip],s));
    
28.     j=f_chip*i+1;
    
29.     end;
    
30. end;
    
31. len_of_spread=length(msg_spread);
    
32. 
    
33. msg_tr=zeros(num_of_user,data_length*f_chip*N);
    
34. for s=1:num_of_user
    
35.     msg_tr(s,:)=dmod(msg_spread(s,:),fc,f_chip,fs,'psk','M');
    
36. end;
    
37. len_of_tr=length(msg_tr);
    
38. 
    
39. for SNRpbit=0:1:7
    
40.     SNR=SNRpbit;
    
41.     rand('state',sum(100*colock));
    
42.     randn('state',sum(100*colock));
    
43.    
    
44. msg_rec_data=zeros(num_of_user,len_of_tr);
    
45. sum_1=zeros(1,len_of_tr);
    
46. msg_received=zeros(1,len_of_tr);
    
47. 
    
48. for s=1:num_of_user
    
49.     msg_rec_data(s,:)=awgn(msg_tr(s,:),SNR-10*log10(N),'measured','dB');
    
50.      for i=1:data_length
    
51.      sum_1=sum_1+msg_rec_data(s,i);
    
52.      msg_received=sum_1;
    
53.      end;
    
54. end;
    
55. 
    
56. msg_demoded=ddemod(msg_received,fc,f_chip,fs,'measured','dB');
    
57. 
    
58.   j=1;
    
59.   for i=1:data_length
    
60.      msg_de_spread(j:(j+f_chip-1))=xor(msg_received(j:(j+f_chip-1))',PN_seq(1:f_chip,1));
    
61.      j=f_chip*i+1;
    
62.   end;
    
63. 
    
64.   j=1;
    
65.   for i=1:data_length
    
66.     sum_2=0;
    
67.     for k=j:j+f_chip-1
    
68.        sum_2=sum_2+msg_de_spread(k);
    
69.     end;
    
70.   if(sum_2>=7)
    
71.     msg_de_spread(i)=1;
    
72.   else
    
73.     msg_de_spread(i)=0;
    
74.   end;
    
75.   j=f_chip*i+1;
    
76.   end;
    
77. 
    
78.   for i=1:data_length
    
79.      if(msg_de_spread(i)==msg_unsprd(i,1))
    
80.      matches=matches+1;
    
81.      else
    
82.      errors=errors+1;
    
83.      end;
    
84.   end;
    
85.   BER_awgn(count)=errors/data_length;
    
86.     count=count+1;
    
87.     errors=0;
    
88.   end;
    
89. end;
    
90.    X=[1:8];
    
91.    semilogy(X,BER_awgn(count),'-.b*');
    
92.    hold on;
    
93.    grid on;
    
94. 

复制代码

happy

简单看了一下错误，很明显就是不仔细，比如
rand('state',sum(100*colock));
randn('state',sum(100*colock));
colock写错了，是clock

PN_seq=(11,num_of_user,[0:1]);
这是什么东西？有这样的表示方法吗？

msg_coded根本就没定义，是什么东西？

其他的没仔细看，自己再好好检查吧

xianjuan

是产生一个PN序列的做法，我打错了，但是我的源程序是对的，还有就是那个msg_coded虽然没有预定义，但是后面我对他进行负值了，我的程序主要是错在
msg_tr=zeros(num_of_user,data_length*f_chip*N);
for s=1:num_of_user
msg_tr(s,:)=dmod(msg_spread(s,:),fc,f_chip,fs,'psk','M');
end;
len_of_tr=length(msg_tr);
主要是调制那句话有问题，无法进行，前面都是对的，是我输入时马虎产生的错误，
还有就是在假如高撕噪声时出错
也就是这句化
msg_rec_data=zeros(num_of_user,len_of_tr);
sum_1=zeros(1,len_of_tr);
msg_received=zeros(1,len_of_tr);

for s=1:num_of_user
msg_rec_data(s,:)=awgn(msg_tr(s,:),SNR-10*log10(N),'measured','dB');
for i=1:data_length
sum_1=sum_1+msg_rec_data(s,i);
msg_received=sum_1;
end;
end;
拜托了，谢谢您！

xianjuan

happy 救命呀！

xianjuan

将程序更正哈！说明一下，我做的多用户干扰抑制，本程序是对多用户通信的仿真，是四个用户同时通信，先对信息进行编码，然后扩频，然后进行PSK调制，然后加入高斯噪声，然后将信息进行相加，再进行解扩，再解密，然后再计算误码率，就这些了，只是在调制那里进行不下去，还有高斯噪声加不上呀！我着急，请您帮忙，拜托了！

happy

<P>把你正确的程序贴一下，你说得好乱，不知道怎么个意思</P>

xianjuan

1. f_data=1;
   
2. f_chip=11;
   
3. fc=220;
   
4. fs=3*fc;
   
5. N=fs/f_chip;
   
6. data_length=5000;
   
7. M=2;
   
8. num_of_user=4;
   
9. matches=0;
   
10. errors=0;
    
11. count=1;
    
12. SNRpbit=0;
    
13. SNR=SNRpbit;
    
14. 
    
15. rand('state',sum(100*clock));
    
16. randn('state',sum(100*clock));
    
17. numplot=100;
    
18. msg_unsprd=randsrc(data_length,num_of_user,[0:M-1]);
    
19. PN_seq=randsrc(11,num_of_user,[0:1]);
    
20. 
    
21. for s=1:num_of_user
    
22. j=1;
    
23. for i=1:data_length
    
24. for k=j:j+f_chip-1
    
25. mdg_coded(s,k)=msg_unsprd(i,s);
    
26. end;
    
27. msg_spread(s,[j:(j+f_chip-1)])=xor(msg_coded(s,[j:(j+f_chip-1)])',PN_seq([1:f_chip],s));
    
28. j=f_chip*i+1;
    
29. end;
    
30. end;
    
31. len_of_spread=length(msg_spread);
    
32. 
    
33. msg_tr=zeros(num_of_user,data_length*f_chip*N);
    
34. for s=1:num_of_user
    
35. msg_tr(s,:)=dmod(msg_spread(s,:),fc,f_chip,fs,'psk','M');
    
36. end;
    
37. len_of_tr=length(msg_tr);
    
38. 
    
39. for SNRpbit=0:1:7
    
40. SNR=SNRpbit;
    
41. rand('state',sum(100*clock));
    
42. randn('state',sum(100*clock));
    
43. 
    
44. msg_rec_data=zeros(num_of_user,len_of_tr);
    
45. sum_1=zeros(1,len_of_tr);
    
46. msg_received=zeros(1,len_of_tr);
    
47. 
    
48. for s=1:num_of_user
    
49. msg_rec_data(s,:)=awgn(msg_tr(s,:),SNR-10*log10(N),'measured','dB');
    
50. for i=1:data_length
    
51. sum_1=sum_1+msg_rec_data(s,i);
    
52. msg_received=sum_1;
    
53. end;
    
54. end;
    
55. 
    
56. msg_demoded=ddemod(msg_received,fc,f_chip,fs,'measured','dB');
    
57. 
    
58. j=1;
    
59. for i=1:data_length
    
60. msg_de_spread(j:(j+f_chip-1))=xor(msg_received(j:(j+f_chip-1))',PN_seq(1:f_chip,1));
    
61. j=f_chip*i+1;
    
62. end;
    
63. 
    
64. j=1;
    
65. for i=1:data_length
    
66. sum_2=0;
    
67. for k=j:j+f_chip-1
    
68. sum_2=sum_2+msg_de_spread(k);
    
69. end;
    
70. if(sum_2>=7)
    
71. msg_de_spread(i)=1;
    
72. else
    
73. msg_de_spread(i)=0;
    
74. end;
    
75. j=f_chip*i+1;
    
76. end;
    
77. 
    
78. for i=1:data_length
    
79. if(msg_de_spread(i)==msg_unsprd(i,1))
    
80. matches=matches+1;
    
81. else
    
82. errors=errors+1;
    
83. end;
    
84. end;
    
85. BER_awgn(count)=errors/data_length;
    
86. count=count+1;
    
87. errors=0;
    
88. end;
    
89. end;
    
90. X=[1:8];
    
91. semilogy(X,BER_awgn(count),'-.b*');
    
92. hold on;
    
93. grid on;

复制代码

xianjuan

拜托了，帮忙呀！

xianjuan

拜托您了，急需！

happy

http://forum.vibunion.com/forum/viewthread.php?tid=10796