Filtering unit for electrocardiography applications

A filtering unit for an electrocardiograph device, the filtering unit comprising:

• a digital signal input interface for receiving a digital electrocardiographic signal sampled at a predetermined sampling frequency (Fs) between 300 and 8000 Hz;
• a data storage connected to the digital signal input interface and configured to store a predetermined number of consecutive recent samples of the digital electrocardiographic signal;
• a finite impulse response filter connected to the data storage and configured to generate and provide a filtered digital electrocardiographic signal using the stored samples, the finite impulse response filter having an impulse response h[n] consisting of a finite ordered sequence of between 900 and 160000 consecutive Kronecker delta pulses δ[n], wherein n is an order of a respective Kronecker delta pulse in the finite ordered sequence, the impulse response formed by
• at least three consecutive sets of one or more consecutive scaled Kronecker delta pulses, all of the scaled Kronecker delta pulses within a respective set having a respective constant amplitude, wherein
• a modulus of the sum of the amplitude of all the Kronecker delta pulses of the impulse response is smaller than 0.1;
• a number of the scaled Kronecker delta pulses of at least one of the sets of Kronecker delta pulses is equal to or higher than a minimum number of Kronecker delta pulses resulting from multiplying the sampling frequency by a time span of 10−2 seconds;
• and wherein
• the data storage is configured to store at least a number of the consecutive recent samples of the digital electrocardiographic signal that is equal to the number of Kronecker delta pulses of the impulse response.