demo of efficient 1-to-8 upsampler

input sample rate 8 kHz, input bandwidth 3.5 k Hz

12 bit dynamic range:

recursive polyphase model first stage 5 coef, second stage 2-coef, third stage 2-coef

approximately two multiplies per output point

generate comb of sinusoids spanning input frequency span-　demo of efficient 1-to-8 upsampler

　input sample rate 8 kHz, input bandwidth 3.5 k Hz

　12 bit dynamic range:

　recursive polyphase model　first stage 5 coef, second stage 2-coef, third stage 2-coef

　approximately two multiplies per output point

　generate comb of sinusoids spanning input frequency span...