- TX: process data at symbol rate

- RX: removed kdown stuff (hardcode to 4), fixed redundant down sampling for base band processing

git-svn-id: http://moon:8086/svn/matlab/trunk@37 801c6759-fa7c-4059-a304-17956f83a07c

ofdm/ofdm_tx.m

@@ -15,8 +15,8 @@ M_QAM = 64;
 RCWIN_ROLLOFF = 0.125;
 
 % Params
-fa = 48000;
-T = 4/fa;
+fa = 12000;
+T = 1/fa;
 
 [ofdm_params, ofdm_spec_occ] = drm_params(mode, bandwidth);
 
@@ -107,12 +107,16 @@ grid;
 plot(wng); grid;
 
 % Modulate on carrier
-yc = exp(j*2*pi.*(0:length(xv)-1)*0.25) .* xv;
+xup = upsample(xv, 4);
+hlp = FIRCalcLowpass(0.25, 129);
+xup = filter(hlp, 1, xup);
+
+yc = exp(j*2*pi.*(0:length(xup)-1)*0.25) .* xup;
 yv = real(yc) + imag(yc);
 
 xv = conj(xv')./abs(max(xv));
 yv = yv'./max(yv);
 
-wavwrite(0.9*yv,fa,16,'yv.wav')
+wavwrite(0.9*yv,4*fa,16,'yv.wav')
 wavwrite(0.9*[real(xv) imag(xv)],fa,16,'xv.wav')