Transitional Butter–Elliptic filter suitable for complementary decomposition

Figures & data

Figure 1. Attenuation characteristic of the transfer function with two extrema in both the passband and the stopband.

Figure 2. Complementary pair attenuation characteristics for the fifth-, seventh- and ninth-order new class filters.

Figure 3. New IIR filter complementary pair attenuation characteristics for the seventh order compared to the Butterworth and the Elliptic filter of the same order for R_s = 40 dB.

Figure 4. The seventh order new class filter poles and zeros in the z plane for M = 3 and L = 2.

Table 1. Transfer function coefficients for the fifth-, seventh- and ninth-order lowpass new class filters.

V order		VII order		IX order
b	a	b	a	b	a
0.1055	1.0000	0.0542	1.0000	0.0224	1.0000
0.3428	0.0000	0.2328	0.0000	0.1312	0.0000
0.5723	0.8966	0.5023	1.4197	0.3690	1.8641
0.5723	0.0000	0.7221	0.0000	0.6793	0.0000
0.3428	0.1447	0.7221	0.5526	0.9098	1.1150
0.1055	0.0000	0.5023	0.0000	0.9098	0.0000
		0.2328	0.0504	0.6793	0.2326
		0.0542	0.0000	0.3690	0.0000
				0.1312	0.0117
				0.0224	0.0000