High pass programmable filter is an advanced device that combines digital signal processing (DSP) technology and analog circuit design. Its core advantage lies in the ability to dynamically adjust different frequency response characteristics through software configuration. The following is a detailed analysis of its working principle:

1、 High pass programmable filter hardware infrastructure

1. Input interface module

Receive raw analog signals or digitized sampled data streams;

Contains an anti aliasing low-pass filter (LPF) that suppresses components above the Nyquist frequency to avoid spectral aliasing.

2. Programmable Logic Unit (PFU)

Composed of Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), or Microcontrollers (MCUs);

Calculate the filtering coefficients in real-time according to the preset algorithm and control the subsequent processing flow.

3. Digital Multiplicative Accumulator (MAC Array)

Implement convolution operations for Finite Impulse Response (FIR) structures, with each tap delay line corresponding to a set of weight parameters;

The typical configuration supports 64~1024 order taps, which determine the steepness of the transition band and the depth of stopband attenuation.

4. Digital to Analog Converter (DAC) and Reconstruction Circuit

Convert the processed digital results into analog signals;

Equipped with a smoothing filter to eliminate quantization noise and image frequency components.

2、 Step by step detailed explanation of the working principle of high pass programmable filters

Step 1: Signal acquisition and preprocessing

The sampling theorem follows: discretize continuous time signals at a speed of at least twice the highest frequency of interest;

DC offset correction: detecting and removing common mode voltage interference through high-resolution ADC;

Automatic gain control (AGC): dynamically adjust the input amplitude to the optimal signal-to-noise ratio range.

Step 2: Digital domain filtering implementation - using two mainstream algorithm architectures:

FIR filtering mechanism

Among them, h [k] is a pre designed impulse response sequence;

Advantages: Strict linear phase characteristics ensure consistent delay of each frequency component, avoiding waveform distortion;

2IIR recursive structure

Realize infinite impulse response through feedback loop;

Advantages: Sharp roll off characteristics can be achieved at lower orders, suitable for resource constrained scenarios;

Attention: Stability issues should be handled with caution to prevent the poles from moving out of the unit circle and causing oscillations.