Techniques for dynamic range enhancement in a frequency-folded broadband channelizer

Abstract

Recent work in spectrum-channelizing receivers has demonstrated the ability to simultaneously detect and down-convert broadband inputs while using a single LO. This addresses a key design challenge in mixer-bank based spectrum channelizers, namely the requirement for multiple concurrently operating frequency-synthesizers. An approach that simultaneously addresses channelization and digitization is the frequency-folded analog-to-digital converter. In this work, the use of feedforward and feedback for linearizing such architectures, by combining them with frequency-synthesis capable harmonic-rejection mixers is proposed. Feedforward-based approaches are effective in relaxing the dynamic range requirement of the sub-ADCs used at baseband, while feedback-based approaches are useful for relaxing dynamic range at the input of the channelizer.