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i i i using software todisplay ean-13 supplement 5 on asp.net web,windows application QR Code ISO speicification i i TranterBook UPC-13 for None --- 2003/11/18 --- 16:12 --- page 139 --- #157. Section 4.9. Appendix A: MATLAB Program QAMDEMO Appendix A: MATLAB Program QAMDEMO Main Program: c4 qamdemo.m % File: c4_qamdemo.m levelx = input( Number of D levels > ); levely = input( Number of Q levels > ); m = input( Number of symbols > ); n = input( Number of samples per symbol > ); bw = input( Filter bandwidth, 0<bw<1 > );% % [xd,xq] = qam(levelx,levely,m,n); % [b,a] = butter(6,bw); % determine filter coefficients yd = filter(b,a,xd); % filter direct coefficient yq = filter(b,a,xq); % filter quadrature coefficient % subplot(2,2,1) % first pane plot(xd,xq, o ) % unfiltered scatterplot a = 1.4; maxd = max(xd); maxq = max(xq); mind = min(xd); minq = min(xq); axis([a*mind a*maxd a*minq a*maxq]) axis equal xlabel( xd ); ylabel( xq ) % subplot(2,2,2) % second pane plot(yd,yq) % filtered scatterplot axis equal; xlabel( xd ); ylabel( xq ); % sym = 30; % number of symbols in time plot nsym = (0:sym*n)/n; % x axis vector for time plots subplot(2,2,3) % third pane plot(nsym(1:sym*n),yd(1:sym*n)) % filtered direct component xlabel( symbol index ); ylabel( xd ); % subplot(2,2,4) % fourth pane plot(nsym(1:sym*n),yq(1:sym*n)) % filtered quadrature component xlabel( symbol index ); ylabel( xq ); % End of script file.

. i i i i i TranterBook 2003/11/18 16:12 page 140 #158. Lowpass Simulation Models for Bandpass Signals and Systems 4 . qam.m Supporting Routines function [xd,xq] = q GS1-13 for None am(levelx,levely,m,n) xd = mary(levelx,m,n); xq = mary(levely,m,n); % End of function file.. mary.m function y= mary(lev Software GS1-13 els,m,n) % m = number of symbols % n = samples per symbol l = m*n; y = zeros(1,l-n+1); lm1 = levels-1; x=2*fix(levels*rand(1,m))-lm1; for i = 1:m k = (i-1)*n+1; y(k) = x(i); end y = conv(y,ones(1,n)); % End of function file.. % Total sequence length % Initalize output vector % Loop to generate info symbols % Make each symbol n samples i i i i i TranterBook 2003/11/18 16:12 page 141 #159. Section 4.10. Appendix B: Proof of Input-Output Relationship Appendix B: Proof of Input-Output Relationship We now formally show that if x(t) and h(t) are de ned as x(t) = Re{x(t) exp (j2 f0 t)} and h(t) = Re{2h(t) exp (j2 f0 t)} then. (4.177). (4.178). y(t) =. x( )h(t ) dy = Re {y(t) exp (j2 f0 t)}. (4.179). where y(t) = x(t) h(t). The proof of (4.179) EAN13 for None is accomplished by substituting x(t) and h(t) in the integral and evaluating the result. Recognizing that the sum of a function and its complex conjugate is twice the real part of the function allows us to express x(t) and h(t) in the form x(t) = and h(t) = h(t) exp (j2 f0 t) + h (t) exp ( j2 f0 t) (4.

181) 1 1 x(t) exp (j2 f0 t) + x (t) exp ( j2 f0 t) 2 2 (4.180). respectively. Substi tuting x(t) and h(t) into the convolution integral yields y(t) as the sum of four integrals. We therefore write y(t) = I1 + I2 + I3 + I4 where I1 = 1 x( ) exp (j2 f0 ) h (t ) exp ( j2 f0 (t )) d 2 1 = exp ( j2 f0 t) x( )h (t ) exp (j4 f0 ) d 2 1 x ( ) exp ( j2 f0 ) h(t ) exp (j2 f0 (t )) d 2 1 = exp (j2 f0 t) x ( )h(t ) exp ( j4 f0 ) d 2 (4.

182). (4.183). I2 =. (4.184). i i i i i TranterBook Software EAN-13 Supplement 2 2003/11/18 16:12 page 142 #160. Lowpass Simulation Models for Bandpass Signals and Systems 4 . I3 =. 1 x( ) exp (j2 f0 EAN-13 Supplement 2 for None ) h(t ) exp (j2 f0 (t )) d 2 1 x( )h(t ) d = exp (j2 f0 t) 2 . (4.185). and I4 = 1 x ( ) Software GS1-13 exp ( j2 f0 ) h (t ) exp ( j2 f0 (t )) d 2 1 = exp ( j2 f0 t) x ( )h (t ) d (4.186) 2 . Note that the integr ands in both I1 and I2 are complex bandpass signals having a center frequency of 2f0 . The envelope of these functions is slowly varying with respect to 2f0 , since the bandwidth of x(t) and h(t) is assumed to be much less than 2f0 . The integral therefore approximately cancels half-cycle by half-cycle.

The approximation that I1 and I2 are negligible improves as f0 increases. Thus, limf0 (I1 and I2 ) = 0. Note also that I3 and I4 are complex conjugates.

Thus:. y(t) = I3 + I4 = I Software EAN 13 3 + I3 = 2 Re{I3 }. (4.187).
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