Realization and performance comparison of untethered and minimally tethered helmet mounted broadband fNIR

Broadband (30–1000MHz) frequency modulated spectroscopic measurements of brain tissue using near infra red wavelengths is used to get an accurate extraction of absorption and scattering coefficients of various regions of brain. The design and realization challenges of developing this system are discussed in this paper. The challenges lie in developing small size, low power consuming, efficient custom designed modules on a helmet for broadband NIR spectroscopy and high speed wireless or minimally wired communications to a remote processing unit. The design requirements and expected performance of the custom designed modules is conducted using IBM 90nm CMOS technology. Finally, a comparison between the system level performance of untethered and a minimally tethered systems is shown in terms power consumption and implementation.