Mixers
Voltage gain in demodulation is a result of integration during the switch on-time
That gain is calculated here for serial switch mixers as function of three different switch on-times
integral (sin x)dx = -cos x
The integral shall be calculated over the on-time of the switch and divided by length of integration time (radians)
in order to get the integrated voltage.
time time     45 degrees on-time   90 degrees on-time   180 degrees on-time  
x x =(-cos(x+22.5) + cos(x-22.5))/ PII()*4 =(-cos(x+45) + cos(x-45))/ PII()*2 =(-cos(x+90) + cos(x-90))/ PII()
degrees radians -cos x   45 deg diff dB   90 deg diff dB   180 deg diff dB  
0.0 0 -1.000        
22.5 0.393 -0.924 0.373 -8.568      
45.0 0.785 -0.707 0.689 -3.235   0.637 -3.922    
67.5 1.178 -0.383 0.900 -0.912   0.832 -1.600    
90.0 1.571 0.000 0.974 -0.224   0.900 -0.912 0.637 -3.922  
112.5 1.963 0.383 0.900 -0.912   0.832 -1.600 0.588 -4.610  
135.0 2.356 0.707 0.689 -3.235   0.637 -3.922 0.450 -6.933  
157.5 2.749 0.924 0.373 -8.568   0.345 -9.255 0.244 -12.266  
180.0 3.142 1.000 0.000 -316.994   0.000 -316.994 0.000 -322.159  
202.5 3.534 0.924 -0.373 -8.568   -0.345 -9.255 -0.244 -12.266  
225.0 3.927 0.707 -0.689 -3.235   -0.637 -3.922 -0.450 -6.933  
247.5 4.320 0.383 -0.900 -0.912   -0.832 -1.600 -0.588 -4.610  
270.0 4.712 0.000 -0.974 -0.224   -0.900 -0.912 -0.637 -3.922  
292.5 5.105 -0.383 -0.900 -0.912   -0.832 -1.600 -0.588 -4.610  
315.0 5.498 -0.707 -0.689 -3.235   -0.637 -3.922 -0.450 -6.933  
337.5 5.890 -0.924 -0.373 -8.568   -0.345 -9.255 -0.244 -12.266  
360.0 6.283 -1.000 0.000 -310.973   0.000 -313.472 0.000 -316.138  
382.5 6.676 -0.924 0.373 -8.568   0.345 -9.255 0.244 -12.266  
405.0 7.069 -0.707 0.689 -3.235   0.637 -3.922 0.450 -6.933  
427.5 7.461 -0.383 0.900 -0.912   0.832 -1.600 0.588 -4.610  
450.0 7.854 0.000 0.974 -0.224   0.900 -0.912 0.637 -3.922  
472.5 8.247 0.383 0.900 -0.912   0.832 -1.600    
495.0 8.639 0.707 0.689 -3.235   0.637 -3.922    
517.5 9.032 0.924 0.373 -8.568      
540.0 9.425 1.000        
                         
Additional power attenuation may come from impedance level change.
24.12.2009 OH1TV
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