It is always very difficult to process the bioelctrical signals, sampling, amplifying and quantifying because of the different sources it comes from and the mechanism it depends on.

• 生物电信号由于其发生机理和所处的生物体的电特性比较复杂、多变，故在处理这样的信号时，常规方法和电路往往难以实现不失真地撷取、放大和精确定量。