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
Help: How to design the audio pre-emphas(J.17) filter.
Started by ●February 6, 2007