Fall 2013 ECE Senior Design:Portable Lock-in Amplifier for Brain-Machine Interfacing

Jamie NortonProfessor Scott Carney

Electroencephalography (EEG)

Steady-state potentials

Brain Machine Interfaces

Noise problem

Software approach

• Essentially seeks to take readings from a standard EEG amplifier, filter and combine them in some way to maximize accurate detection of steady-state potentials.

• Variety of Methods– PSDA– MEC– CCA– Modified CCA

Hardware Approach: Lock-in AmplifierIf we have some sinusoidal signal, and a reference signal.

And we multiply them…

Goals

• Develop a simple and portable lock-in amplifier for the detection of SSVEP signals.

• Explore their use under ideal and non-ideal conditions.

• Combine with EEG recordings to detect SSVEP entrainments by end of semester.

References• Lock-in Amplifier Design

http://www.youtube.com/watch?v=luiDMVAsyTc

• http://www.phys.utk.edu/labs/modphys/lock-in%20amplifier%20experiment.pdf