1!IIR 2! TSP Lab 3! Electrical & Computer Engineering 4! McGill University 5! File: STL_LPx3_IIR.cof 6! See ITU-T G.191 (2000), Software Tools Library (module iir_flat.c) 7! $Id: STL_LPx3_IIR.cof 1.4 2002/06/18 AFsp-v8r2 $ 8! 9! IIR flat response filter for 1:3 or 3:1 resampling. This filter can be 10! used to convert between 48 kHz sampling and 16 kHz sampling. 11! Each line gives the 5 coefficients for a second-order section 12! h(i,0)*z^2 + h(i,1)*z + h(i,2) 13! H(i,z) = ------------------------------ 14! z^2 + h(i,3)*z + h(i,4) 15! - 7th order elliptic filter (equi-ripple) 16! - Passband: unity gain, 0 - 7010 Hz (48 kHz sampling), ripple +0 / -0.1 dB 17! - Stopband: 7610 - 24000 Hz (48 kHz sampling), min. attenuation 97.6 dB 18! - For interpolation, apply an additional gain factor of 3 19 2.5520133e-004 2.5520133e-004 0.0000000e+000 -7.4139393e-001 0.0000000e+000 20 1.0000000e+000 8.5931258e-001 1.0000000e+000 -1.4463527e+000 5.9986938e-001 21 1.0000000e+000 -2.6100419e-001 1.0000000e+000 -1.3653687e+000 7.1199842e-001 22 1.0000000e+000 -7.4898158e-001 1.0000000e+000 -1.2868815e+000 8.2250087e-001 23 1.0000000e+000 -9.5697448e-001 1.0000000e+000 -1.2334203e+000 9.0217520e-001 24 1.0000000e+000 -1.0480535e+000 1.0000000e+000 -1.2060405e+000 9.5276796e-001 25 1.0000000e+000 -1.0831175e+000 1.0000000e+000 -1.2007704e+000 9.8602848e-001 26