Svante Signell

Quantization noise analysis of wave digital and lossless digital integrator allpass/lattice filters

Quantization noise levels of two low-sensitive allpass filter structures, namely wave digital circulator filters (WDCF) and lossless digital integrator filters (LDIF), are compared. Allpass filters are of interest for design of lowpass and bandpass lattice filters. The results show, primarily, that second-order LDIFs have lower total quantization noise gains than corresponding WCDFs for any pole configuration within the right half-circle of the z plane. The benefit of using ladder LDIFs rather than cascaded first and second order sections is also demonstrated.