Efficient Sample Rate Conversion for Multi-Standard Software Defined Radios

Abstract

This paper presents a modified structure based on cascaded integrator comb (CIC) filters and polynomial interpolation to perform arbitrary sample rate alterations. Incorporating CIC compensation filter within the polynomial interpolator has obviated programmable filter typically used in the process. It has also been shown that a maximum passband ripple of 0.5 dB is attainable with comparatively fewer computations. The ensuing design leads to an efficient realization both in terms of computational complexity and hardware utilization. This architecture is especially useful in the digital IF stage of emerging multi-standard wireless transceivers where fractional sample rate conversion with large relatively prime factors is required. Proposed solution has been tested by implementing it in a software radio simulation model supporting three commercial wireless communication standards, namely GSM, IS-95 and UMTS.