Non-idealities Compensation in Full-Digital Receivers with Application to Ultra-Wide Band

Nowadays many transceivers adhere to full-digital design principles, with the basic operations performed in the analog domain (filtering, down-conversion) and the whole remaining processing postponed to the digital domain (including matched filtering and synchronization). Though the operations in the analog front-end are ideally reversible, hence no signal degradation should occur before the analog-to-digital conversion (thus preserving the information integrity), however the intrinsic non-idealities in the circuitry may introduce a certain level of distortion. In this paper we provide a simple and flexible approach for the compensation of these effects. We derive useful formulas for obtaining a digital compensation filter by means of a direct transformation of the analog system coefficients. This allows to easily perform the compensation in the digital domain via fast Fourier transform. To illustrate the procedure, the case-study of a ultra-wide band receiver is addressed. Numerical results show that an improvement of more than 1 dB can be obtained at bit-error rate of interest for the applications. Sample code is also provided for an easy implementation.