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#### viswanath

I have a question regarding mixing discrete sine waves. If you have

two sine waves sin(w1*t) and sin(w2*t) and they are sampled at the

same rate. If you are mixing them in a receiver operation, we are

supposed to get at the output of the mixer the sum and difference of

frequencies. But it is just the values that we are multiplying isn't

it, at the sampled time instants?

How do we end up getting a difference frequencies and sum frequencies

which have to be low pass filtered? If I implemented this in VHDL and

used math_real library functions sin() and real variables, I would

just be multiplying the two numbers at each time sample. This value

would encompass the frequency of the sine wave. However I donot

understand how I would be getting a difference in frequency and sum in

frequency terms?

I have read from trigonometry and analog communications but somehow I

am missing some essence here. Could you please let me know how the

above is possible?

I would greatly appreciate a response.

Thanks,

Viswanath