DocumentCode :
506245
Title :
Asynchronous signal processing for brain-computer interfaces
Author :
Senay, Seda ; Chaparro, Luis F. ; Sun, Mingui ; Sclabassi, Robert ; Akan, Aydin
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Pittsburgh, Pittsburgh, PA, USA
fYear :
2009
fDate :
5-8 Nov. 2009
Abstract :
Brain-computer interfaces (BCIs) provide a way to monitor and treat neurological diseases. An important application of BCIs is the monitoring and treatment of epilepsy, a neurological disorder characterized by recurrent unprovoked seizures, symptomatic of abnormal, excessive or synchronous neuronal activity in the brain. BCIs contain an array of sensors that gather and transmit data under the constrains of low-power and minimal data transmission. Asynchronous sigma delta modulators (ASDMs) are considered an alternative to synchronous analog to digital conversion. ASDMs are non-linear feedback systems that enable time-encoding of analog signals, equivalent to non-uniform sampling. An efficient reconstruction of time-encoded signals can be achieved using a prolate spheroidal waveform (PSW) projection. PSWs have finite time support and maximum energy concentration within a given bandwidth. The original signal can be reconstructed from the ASDM time-encoded binary signal. For transmission, we propose a modified orthogonal frequency division multiplexing (OFDM) technique using chirp modulation. Our method generalizes the chirp modulation of binary streams with non-uniform symbol duration.
Keywords :
OFDM modulation; brain-computer interfaces; delta-sigma modulation; encoding; medical signal processing; neurophysiology; signal reconstruction; ASDM time-encoded binary signal; abnormal neuronal activity; asynchronous sigma delta modulators; asynchronous signal processing; brain-computer interfaces; chirp modulation; epilepsy; finite time support; maximum energy concentration; neurological diseases; nonlinear feedback systems; nonuniform symbol duration; orthogonal frequency division multiplexing; prolate spheroidal waveform projection; recurrent unprovoked seizures; signal reconstruction; synchronous neuronal activity; time-encoded signals; Brain computer interfaces; Chirp modulation; Diseases; Epilepsy; Monitoring; OFDM; Sensor arrays; Sensor phenomena and characterization; Signal processing; Variable speed drives;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Electrical and Electronics Engineering, 2009. ELECO 2009. International Conference on
Conference_Location :
Bursa
Print_ISBN :
978-1-4244-5106-7
Electronic_ISBN :
978-9944-89-818-8
Type :
conf
Filename :
5355003
Link To Document :
بازگشت