Digital filter design: Examples and Answers

The ASN Filter offers professional designers and beginners alike a powerful, modern and fully interactive real-time development and experimentation platform for digital filter design and signal analysis in one tool. Specifications are entered and modified graphically, which removes the need for detailed understanding of mathematics and technical specifications. However, for specialists we’ve included a filter scripting language, which allows for the experimentation of bespoke transfer functions via symbolic mathematics. In all cases, designs may be validated and optimised in real-time via the signal analyser interface, which also incorporates a comprehensive signal generator.

Yes. The tool supports deployment options to Matlab/Octave, Scilab and ANSI C. We’ve also bundled example development software for all listed frameworks, allowing you to import your designed filter and use it directly with your algorithm or application.

Absolutely. Although the ASN filter designer is a Windows based application, several of our Mac clients have had no problems running it via the Parallels Desktop virtualisation machine software. For Linux users, the VMware virtualisation machine software leads to good results.

From the discussions that we’ve have had with academics, many students these days have weak mathematical skills, so the traditional way of teaching filter design is very challenging. Many of the lecturers said the tool successfully helped them to graphically illustrate the concept of filtering and the effects of poles and zeros without any mathematics. This point combined with the bonus of the built in signal analyser allows for a simple introduction into signal analysis, while at the same time, allowing them show the effects of changing the filter characteristics on a streaming signal – something that’s not available in many other tools.

ASN provides a free of charge STEM education package, comprising of worked examples and code.

The Educational licence is intended for organisations (i.e. universities, colleges and research institutes) involved in non-commercial projects only. If your organisation is undertaking a commercial project, then you need to purchase a Professional licence.

We offer users two flavours of licence: perpetual and subscription based.

The offering is as follows:

• Quarterly
• Yearly based
• Perpetual

The quarterly subscription is a good option for those who are looking to create a filter for just one project, or just want to see if the ASN Filter Designer fits their way of working.

With a 3 month or yearly based subscription licence, you’ll get full support and upgrades during this period. However, you need to have an internet connection while working with ASN Filter Designer.

With a perpetual licence, you can use your version of ASN Filter Designer as long as you want. The first year, you’ll get full support and upgrades. After this year, you can choose to upgrade your licence’s maintenance.

The Bessel prototype is not supported in the main filter designer, as the Bilinear transform warps the linear phase characteristics. However, a Bessel filter design method is available in ASN FilterScript