Bandpass Sampling Digital Frontend Architecture for Multi-Band Access Cognitive Radio

Abstract

Bandpass sampling (BPS) theory enables the conversion of RF frequency directly down to baseband, which is a significant technique in Cognitive radio (CR) systems because they require flexibility in RF frontend. Based on this concept, second-order BPS frontends for CR systems are designed and verified by using a hardware platform. The methods adopted to manipulate spectrums to remove aliasing and images are described, and the equations employed to design interpolants are provided. The results of experiment indicate that the proposed second-order BPS frontends can realize universal access and environment sensing functionalities in CR systems.