This document describes a general system for noise reduction, as well as a
specific system for Magnetic Resonance Imaging (MRI) and Nuclear
Quadrupole Resonance (NQR). The general system, which is called
Calculated Readout by Spectral Parallelism (CRISP), involves
reconstruction and recombination of frequency-limited broadband data
using separate narrowband data channels to create images or signal
profiles. A multi-channel CRISP system can perform this separation using
(1) frequency tuned hardware, (2) a frequency filter-bank (or
equivalent), or (3) a combination of implementations (1) and (2). This
system significantly reduces what we call cross-frequency noise, thereby
increasing signal-to-noise-ratio (SNR). A multi-channel CRISP system
applicable to MRI and NQR are described.