LAUSR

ABSTRACT This paper investigates the design problem of a multidimensional IIR notch filter. To address this issue, a 3-D recursive digital notch filter is considered. A closed-form analytical solution of the notch filter is firstly derived and used for its realisation. The latter is achieved through two types of filters: i) a 3-D IIR straight line filter and ii) 3-D IIR filter with order 111 based on all-pass sections. The straight-line filter is designed by frequency transformation of 3-D analogue prototype filter where a prescribed notch frequency is localised. The IIR filter is realised in proposed lattice structure as a cascade of all-pass sections where the 3-dB bandwidth of the notch filter can be adjusted by the lattice coefficient of the IIR filter independently.