Currently

EEG equipment is expensive and bulky. Their real -time performance is weak

and their signals are easy to be distorted. Therefore

the low - cost portable EEG signal acquisition system based on DSP is developed in this paper. In this system

weak EEG signals are induced to the pre -processing circuits by a noninvasive method with bipolar leads

where they will undergo multi - level amplifying and filtering. After that

the analog signals are converted into digital signals using ADS8320. These digitized signals are digitally filtered in DSP （TMS320VC5509） so that the power interference and physiological artifacts are removed with LMS （Last Mean Square） algorithm and ICA （Independent Component Analysis） algorithm. Experimental results show that the system can meet the design requirements

acquire weak EEG signals in real-time

display and save the processing results. The acquisition system is easy to use and carry

and helpful to the popularity of community-based and family-based EEG diagnostic equipments. Not only does it meet quality requirements

but also economic requests.