Structurally passive resonator-based digital filters

An implementation of FIR (finite impulse response) and IIR (infinite impulse response) filter transfer functions is presented that is structurally passive and hence has very low passband sensitivity. This implementation is based on G. Peceli´s (1986) common structure for recursive discrete transforms. This structure consists of digital resonators in a feedback loop. It is shown that, by locating the resonator poles properly, the passivity of the feedback loop can be easily guaranteed. It is also shown that, by applying appropriate quantization strategy, this structure is able to suppress zero-input limit cycles