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Help: How to design the audio pre-emphas(J.17) filter.

Started by huhu February 6, 2007
Hi,
I'm working on a Nicam modulator in fpga,and such a system is
required
to perform pre-emphasis on the audio channels.Pre-emphasis filter
specified
 in the CCITT J.17 recommendation.
Has anybody implemented this pre-emphasis filter and could you give me
some
tips on how you generated the coefficients?

The pre-emphasis attenuation curve is given by the followingformula:
Insertion loss between nominal impedances =

10 log10 ( (75 + (w/3000)^2) / (1 + (w/3000)^2) ) dB

where 'w' is the angular frequency corresponding to frequency 'f'.

Some values are given .
f (kHz)    Insertion loss (dB)
0          18.75
0.05       18.70
0.2        18.06
0.4        16.48
0.8        13.10
2          6.98
4          3.10
6.4        1.49
8          1.01
10         0.68

Thank you for your help!

huhu