title: Note: A simple broad bandwidth undersampling frequency-domain digital diffuse optical spectroscopy system.
abstract: Near-Infrared frequency-domain technologies, such as Diffuse Optical Spectroscopy (DOS), have demonstrated growing potential in a number of clinical applications. The broader dissemination of this technology is limited by the complexity and cost of instrumentation. We present here a simple system constructed with off-the-shelf components that utilizes undersampling for digital frequency-domain dDOS measurements. Broadband RF sweeps (50-300 MHz) were digitally sampled at 25 MSPS; amplitude, phase, and optical property extractions were within 5% of network analyzer derived values. The use of undersampling for broad bandwidth dDOS provides a significant reduction in complexity, power consumption, and cost compared with high-speed ADCs and analog techniques.
authors.affiliation: Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02115.
authors.forename: Justin
authors.initials: J
authors.lastname: Jung
authors.affiliation: Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02115.
authors.forename: Raeef
authors.initials: R
authors.lastname: Istfan
authors.affiliation: Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02115.
authors.forename: Darren
authors.initials: D
authors.lastname: Roblyer
mesh_terms: D004867:Equipment Design; D055096:Optical Devices; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation* / Q000379:methods*
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