Design of stable IIR digital filters with equiripple passbands and peak-constrained least squares stopbands

This paper describes an algorithmic development for the design of stable IIR digital filters with equiripple passbands and peak-constrained least squares stopbands (ERPP-CLSS). Central to the development is a re-formulation of the design problem as an iterative quadratic programming problem where the stability and ERPPC requirements are met by imposing a system of linear inequalities constraints while the LSS property is satisfied by employing a weighted least squares type objective function.