本题主要是显示周期序列的。
1、代码:
%% ------------------------------------------------------------------------ %% Output Info about this m-file fprintf(‘\n***********************************************************\n‘); fprintf(‘ <DSP using MATLAB> Problem 2.3.1 \n\n‘); time_stamp = datestr(now, 31); [wkd1, wkd2] = weekday(today, ‘long‘); fprintf(‘ Now is %20s, and it is %7s \n\n‘, time_stamp, wkd2); %% ------------------------------------------------------------------------ %% %% {...,-2,-1,0,1,2,...} %% * %% Plot 5 periods self_length = 5; periods = 5; n = [-2:(2+(periods-1) * self_length)];x = [-2,-1,0,1,2]; xtilde = x‘ * ones(1,periods); xtilde = (xtilde(:))‘; figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.1‘); set(gcf,‘Color‘,‘white‘); stem(n,xtilde); title(‘Sequence in Problem 2.3.1‘); xlabel(‘n‘); ylabel(‘xtilde(n)‘);grid on;
显示结果:
2、代码:
%% ------------------------------------------------------------------------ %% Output Info about this m-file fprintf(‘\n***********************************************************\n‘); fprintf(‘ <DSP using MATLAB> Problem 2.3.2 \n\n‘); time_stamp = datestr(now, 31); [wkd1, wkd2] = weekday(today, ‘long‘); fprintf(‘ Now is %20s, and it is %7s \n\n‘, time_stamp, wkd2); %% ------------------------------------------------------------------------ %% %% exp(0.1n)[ u(n) - u(n-20)] 0-20 valid %% %% Plot 3 periods [0;3*20-1] [0,59] n = [0:20]; % We can get self_periods=21 from here x = exp(0.1*n) .* (stepseq(0,0,20) - stepseq(20,0,20)); %x = (stepseq(0,0,20) - stepseq(20,0,20)); figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.2 x(n)‘); set(gcf,‘Color‘,‘white‘); stem(n,x); title(‘x(n) Sequence‘); xlabel(‘n‘); ylabel(‘x(n)‘);grid on; self_length = 21; periods = 3; n1 = [0:20 + (periods-1) * self_length]; xtilde = x‘ * ones(1,periods); xtilde = (xtilde(:))‘; figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.2‘); set(gcf,‘Color‘,‘white‘); stem(n1,xtilde); title(‘Sequence in Problem 2.3.2‘); xlabel(‘n‘); ylabel(‘xtilde(n)‘);grid on;
运行结果:
3、代码:
%% ------------------------------------------------------------------------ %% Output Info about this m-file fprintf(‘\n***********************************************************\n‘); fprintf(‘ <DSP using MATLAB> Problem 2.3.3 \n\n‘); time_stamp = datestr(now, 31); [wkd1, wkd2] = weekday(today, ‘long‘); fprintf(‘ Now is %20s, and it is %7s \n\n‘, time_stamp, wkd2); %% ------------------------------------------------------------------------ %% %% sin(0.1*pi*n)[ u(n) - u(n-10)] 0-10 valid %% %% Plot 4 periods n = [0:10]; % We can get self_periods=11 from here x = sin(0.1*pi*n) .* (stepseq(0,0,10) - stepseq(10,0,10)); figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.3 x(n)‘); set(gcf,‘Color‘,‘white‘); stem(n,x); title(‘x(n) Sequence‘); xlabel(‘n‘); ylabel(‘x(n)‘);grid on; self_length = 11; periods = 4; n1 = [0:10 + (periods-1) * self_length]; xtilde = x‘ * ones(1,periods); xtilde = (xtilde(:))‘; figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.3‘); set(gcf,‘Color‘,‘white‘); stem(n1,xtilde); title(‘Sequence in Problem 2.3.3‘); xlabel(‘n‘); ylabel(‘xtilde(n)‘);grid on;
运行结果:
4、代码:
%% ------------------------------------------------------------------------ %% Output Info about this m-file fprintf(‘\n***********************************************************\n‘); fprintf(‘ <DSP using MATLAB> Problem 2.3.4 \n\n‘); time_stamp = datestr(now, 31); [wkd1, wkd2] = weekday(today, ‘long‘); fprintf(‘ Now is %20s, and it is %7s \n\n‘, time_stamp, wkd2); %% ------------------------------------------------------------------------ %% %% {...,1,2,3,...} + {...,1,2,3,4,...} n=[0:24] %% * * %% what is the periods self_length1 = 3; periods1 = 8; n1 = [0:(2+(periods1-1) * self_length1)]; x1 = [1, 2, 3]; xtilde1 = x1‘ * ones(1,periods1); xtilde1 = (xtilde1(:))‘; figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.4 Period Seq 1‘); set(gcf,‘Color‘,‘white‘); stem(n1,xtilde1); title(‘Sequence {...,1,2,3,...}‘); xlabel(‘n‘); ylabel(‘xtilde1(n)‘);grid on; self_length2 = 4; periods2 = 6; n2 = [0:(3+(periods2-1) * self_length2)]; x2 = [1, 2, 3, 4]; xtilde2 = x2‘ * ones(1,periods2); xtilde2 = (xtilde2(:))‘; figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.4 Period Seq 2‘); set(gcf,‘Color‘,‘white‘); stem(n2,xtilde2); title(‘Sequence {...,1,2,3,4,...}‘); xlabel(‘n‘); ylabel(‘xtilde2(n)‘);grid on; x = xtilde1 + xtilde2 %[x,n] = sigadd(xtilde1,24,xtilde2,24); figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.3.4‘); set(gcf,‘Color‘,‘white‘); stem(x); title(‘Sequence {...,1,2,3,...} + {...,1,2,3,4,...}‘); xlabel(‘n‘); ylabel(‘x(n)‘);grid on;
运行结果:
时间: 2024-10-03 22:29:58