could someone please help me with the following question
On the NanoBoard the anti-aliasing and reconstruction filters are passive low pass filters both with nominal cut-off frequencies around
10 kHz. The Maxim MAX1104 is a full codec and so contains both analogue to digital (A2D) and digital to analogue (D2A) converters, these being represented by the sample and hold (S/H) plus quantiser (Q) and D/A blocks in Figure 1 respectively. Finally, the DSP block in Figure 1 is where the difference equation for implementing the desired digital filter is performed. figure 1 is a block diagram of the following
x(t)->anti-aliasing filter->S/H->Q->DSP->D/A->reconstruction filter->y(t)
1. Bearing in mind that the anti-aliasing filter on the NB1 is not ideal, explain what happens to the analogue signal, x(t), after it has passed through this filter and is presented to the input of the A2D,
when:
b. x(t) is a square wave (50% duty cycle) of fundamental frequency 4 kHz. Hint, think about what the Fourier series representation of this square wave signal is.
My main question is how do i calculate the harmonics of this square wave to see which ones will get cut off
Any help would be appreciated, Thanks.
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