# Categorydigital signal processing

## Single pole filter without multiplications.

When I am working in a design for an FPGA, which involves the acquisition of any signal, I usually have to design a filter before using that signal in the control loop, or a protection. If the use of this…

## Designing a filter on MATLAB and verifying it using FPGA-in-the-loop and Eclypse Z7

If I say “software for engineering”, most of you probably think of MATLAB. I don’t know if there is any field in engineering which does not have a package in MATLAB, and digital signal processing and FPGA design are certainly…

## Implementing high order filters with FIR Compiler.

Many times, in our designs we find a signal that our interest band of frequency is very close to the band that we need to reject. In this cases, in general, the most efficient way to attenuate the unwanted signal…

## Equalizing IIR filters for a constant group delay.

In the previous post I have design an audio equalizer. On that design I have used 3 different FIR filters to split 3 different frequency bands in order to send them to different speakers. Very low frequencies will be sent…

## Audio equalizer based on FIR filters.

Digital signal processing can be used in almost all engineering field, from seismology, to obtain the distance where an earthquake has been generated, to data science, but these areas use digital signal processing as a way to obtain the real…

## Adding windows to xFFT IP.

Digital signal processing algorithms are, in general, purely mathematical algorithms that works perfectly on our notebook or MATLAB, but in real design, the algorithm starts to return us some unexpected results. One example of that is the quantification error. While…

## Implementing a FIR filter using folding.

In this blog we have seen how to develop a FIR filter. In this post you have an example of FIR filter where the coefficients are configured though AXI4-Lite interface. The goal of that post was the implementation of a…

## Implementing a digital biquad filter in Verilog.

Filtering is likely the most common DSP algorithm that any embedded engineer has to design, no matter it they are developing for an STM32, or TI DSP or, of course, en FPGA. Filtering is such important because the majority of…

## Managing AXI4-Stream from MATLAB.

For developers who work with FPGA and digital signal processing, and for signal processing I mean audio signals, video signals, radio signals, … sure they have used the AXI4-Stream protocol. The AXI4-Stream protocol is used as a standard interface to…

## Using FPGA Data Capture to debug a design.

On the project developed on the last 2 posts, to verify the behavior of the filter, we had used the data acquired from the ILA. Data was processed on MATLAB with a script where we read the csv, and verify…