Posts

Many IoT applications use a sinewave for estimating the amplitude of an entity of interest – some examples include:

  • Measuring material fatigue/strain with a loadcell – in vehicle and bridge/building applications measuring material fatigue and strain is essential for safety. An AC sinusoidal excitation overcomes the difficulty of dealing with instrumentation electronics DC offsets.
  • Calibrating CT (current transformers) sensors channels – a sinusoid of known amplitude is applied to channel input and the output amplitude is measured.
  • Measuring gas concentration in infra-red gas sensors – the resulting sinusoid’s amplitude is used to provide an estimate of gas concentration.
  • Measuring harmonic amplitudes in power quality smart grids applications – in 50/60Hz  power systems, certain harmonic amplitudes are of interest.
  • ECG biomedical compliance testing – channel compliance with IEC regulations needed for FDA testing typically uses a set of sinewaves at known amplitudes, to ensure that the channel amplitude error is within specification.

In a previous article, we discussed how differentiation could be used to find the peaks and troughs of sinewave, i.e. finding the zero crossing points. However, a much more traditional approach has been to use fullwave rectification, whereby a non-linear operator and lowpass filtering are employed. The concept used is described below:

  1. Remove any DC or low-frequency offsets via a highpass filter.
  2. Apply a non-linear operator via an abs() or sqr() non-linear operator.
  3. Lowpass filter the result to obtain an estimate of the sinusoid’s amplitude.
  4. Scale the amplitude.

Although this sounds easy, care should be taken to understand the effects of how the non-linear operator alters the waveform and affects the estimation of amplitude using lowpass filtering.

IoT application

A typical IoT application using a sinusoid is shown below:

As seen, the waveform can be modelled as:

\(x\left(n\right)=A\,sin\left(2\pi f_ot\right)+B\)

Where, \(f_o\)  is the frequency of oscillation and \(A\) is the amplitude of sinusoid respectively. Notice that the sinusoid is non-linear and symmetrical around the offset, \(B\). Notice also that it has a peak-to-peak amplitude of \(2A\), since specifying an amplitude \(A\) results in a bipolar amplitude of \(±A\). As many microcontrollers employ low-cost unipolar ADCs, the bipolar sinusoid needs to be offset by a DC offset, \(B\) (usually achieved by a resistor network) to ensure that the signal remains within the common-mode range of the ADC input.

As mentioned above, before applying the non-linear operator any DC offsets need to be removed. This can easily be achieved with either an IIR or FIR highpass filter. If using an IIR filter, it should be noted that the filter’s phase and group delay (latency) will significantly increase at the cut-off frequency, so a degree of experimentation is required to find a good trade-off.

After highpass filtering the data, we can apply the non-linear operator. Two popular operators are the abs()and sqr() operators.

Using the abs() operator, the Fourier series of \(\left|A \,sin(2\pi f_ot)\right|\) is shown below:

\(\left|A\ sin(2\pi f_ot)\right|\ =\ \displaystyle A\left[ \frac{2}{\pi}\ -\ \displaystyle\frac{4}{\pi}\normalsize{\sum\limits_{k=1}^{\infty}}\frac{cos(4k\pi f_ot)}{4k^2-1}\right]\)

Analysing the equation, it can be seen that the abs() operation doubles the frequency and that the DC component is actually \(\frac{2A}{\pi}\), as illustrated below.

As seen, lowpass filtering this result in its current form will produce an amplitude estimate of \(\frac{2A}{\pi}\) (dashed red line), which is clearly incorrect for estimating the sinewave’s amplitude, \(A\). However, this can be simply remedied by scaling the amplitude estimates by \(\frac{\pi}{2}\), which removes the bias, leaving the sinewave’s amplitude, \(A\).

Likewise, for a sqr() operator, we can define the resulting waveform using trigonometrical identities, i.e.

\({sin^2(2\pi f_ot)}\ =\ A\left[\displaystyle\frac{1\ -\ cos(4\pi f_ot)}{2}\right]\)

Lowpass filtering this signal requires a correction scaling factor of 2.  

Lowpass filter

Although any lowpass filter will suffice, the moving average filter is used by most developers by virtue of its computational simplicity and noise reduction characteristics. A more detailed explanation of moving average filters can be found here.

A 24th order moving average filter with a post gain of \(\frac{\pi}{2}\) or 1.571 is shown below.

Applying this moving average filter to a sinewave \(f_o=10Hz, A=0.5\), sampled at 500Hz processed with the abs()operator we obtain the following:

As seen, the amplitude estimation of the sinusoid using a lowpass filter and the \(\frac{\pi}{2}\) scaling factor is now correct. However, for real world applications that contain noise, it is considered to be more accurate to measure the RMS amplitude, in which case the scaling factor becomes \(\frac{\pi}{2\sqrt 2} \).

As a final point, these scaling factors are only valid for sinusoidal scaling. If your waveform is non-sinsoidual (e.g. triangular or square) another scaling factor will be required.

Author

  • Dr. Sanjeev Sarpal

    Sanjeev is an AIoT visionary and expert in signals and systems with a track record of successfully developing over 25 commercial products. He advises top international blue chip companies on their AIoT solutions and strategies for I4.0, telemedicine, smart healthcare, smart grids and smart buildings.

AIoT is an exciting new area that combines AI concepts (i.e. ML) with IoT in order to produce state-of-the-art smart embedded solutions. This augmentation of technologies requires a new set of tools to capture real-time IoT sensor data, analyse it, design suitable algorithms and then perform validation of the solution.  After completing validation of the algorithms on the test data, a final hurdle is then how to generate efficient C code of the developed algorithm(s) for an Arm Cortex-M microcontroller for use in an application. These concepts will be discussed herein.

Arm’s Synchronous Data Stream (SDS) Framework provides developers with an easy method of capturing and playing back real-time sensor data for embedded AIoT sensor applications on Arm Cortex-M processors, such as ST Microelectronics’ very popular STM32 family.

The SDS Framework provides embedded developers with a variety of essential tools, such as the ability to record real-world sensor data for analysis and development in tools such as ASN Filter Designer, Python and Matlab. A set of Python utility scripts are available for recording, playback, visualisation and data conversion, where the latter supports the conversion of captured SDS data files into a single CSV file – providing a simple bridge between the ASN Filter Designer and the SDS Framework.

The SDS framework also supports the possibility to playback real-world data for algorithm validation using Arm Virtual Hardware, allowing developers to verify execution of DSP algorithms on Cortex-M targets with off-line tools.

This application note provides AIoT developers with a complete reference guide of how to develop and deploy feature extraction algorithms for use in AIoT applications to STM32 Arm Cortex-M based microcontrollers using STM32CubeIDE or Keil mVision with the Arm SDS framework and ASN Filter Designer. As mentioned above, AIoT system challenges and concepts will also be covered.

Building AIoT systems

Almost all IoT embedded sensor applications require some level of signal processing to enhance sensor data and extract features of interest. However, an obvious hurdle for many developers is how to design, test and deploy efficient algorithms for their application. This is easier said than done, as many software engineers are not well-versed in understanding the mathematical concepts needed to implement algorithms. This is further complicated by the challenge of how to implement algorithms developed by researchers that are not interested/experienced in developing real-time embedded applications.

A possible solution offered by the Mathworks (Embedded Coder) automatically translates Matlab algorithms and functions into C for Arm processors, but its high price tag and steep learning curve make it unattractive for many.

That being said, Arm and its rich ecosystem of partners provide developers with extensive easy-to-use tooling and tried and tested software libraries. Arm’s CMSIS-DSP and CMSIS-NN frameworks for algorithm development and machine learning (ML) are two very popular examples that are open source and are used internationally by tens of thousands of developers.

The Arm CMSIS-DSP software framework is particularly interesting as it provides IoT developers with a rich collection of fast mathematical and vector functions, interpolation functions, digital filtering (FIR/IIR) and adaptive filtering (LMS) functions, motor control functions (e.g. PID controller), complex math functions and supports various data types, including fixed and floating point. The important point to make here is that all of these functions have been optimised for Arm Cortex-M processors, allowing you to focus on your application rather than worrying about optimisation.  

The Arm-CMSIS framework solutions are strengthened by Arm partners ASN and Qeexo who provide developers with easy-to-use real-time filtering, feature extraction (ASN Filter Designer) and ML tooling (AutoML) and reference designs, expediting the development of AIoT applications, including industrial, audio and biomedical. These solutions have been optimised for Arm processors with the help of Arm’s architecture experts and insider knowledge of compiler workings.

AIoT system building blocks

An essential pre-building block in any AIoT system is the feature extraction algorithm. The challenge for any feature extraction algorithm is to extract and enhance any relevant sensor data features in noisy or undesirable circumstances and then pass them onto the ML model in order to provide an accurate classification.  The concept is illustrated below:

As seen above, an AIoT system may actually contain multiple feature blocks per sensor and in some cases fuse the features locally before sending them onto the ML model for classification such that the system may then draw a conclusion. The challenge is therefore how to capture sensor data for training and design suitable algorithms to extract features of interest.

Feature extraction algorithms: challenges and solutions

The challenge for any feature extraction algorithm is to extract and enhance any relevant data features in noisy data or undesirable circumstances and then pass them onto the ML model in order to provide an accurate classification. Unfortunately, many ML models perform badly, due to poor quality data and insufficient training data.   An obvious challenge for AIoT is how do we obtain the training data in the first place? In many cases, this is extremely challenging as data pertaining to faults (such as preventive maintenance) is hard to come by, as many plant managers are reluctant to break their working production lines or processes to provide developers with training data.

In the absence of adequate training data, feature extraction based on science and mathematics is a prudent alternative, as less training data is required, and in general, the quality of the feature estimate is higher as knowledge of the underlying process is used. Examples include: obtaining accurate pulse and heart rate estimates from ECG and PPG sensors in smartwatch applications when a subject is moving.  For industrial sensors, such as loadcells, pressure, temperature, gas and accelerometer sensors the challenge is amplified, as harsh operating conditions and the sheer variety of the applications needed for I4.0 process control applications complicate the design significantly.

Example: Infrared gas sensor

Consider the following application for gas concentration measurement from an Infrared gas sensor. The requirement is to determine the peak-to-peak amplitude of the sinusoid in order to get an estimate of gas concentration – where the bigger amplitude is the higher the gas concentration will be.

Analysing the Figure, it can be seen that the sinusoid is corrupted with measurement noise (shown in blue), and any estimate based on the blue signal will have a high degree of uncertainty about it – which is not very useful for getting an accurate reading of gas concentration! After cleaning the sinusoid with a digital filter (red line), we obtain a much more accurate and usable signal for our gas concentration estimation challenge. But how do we obtain the amplitude?

Knowing that the gradient at the peaks is zero, a relatively easy and robust way of finding the peaks of the sinusoid is via numerical differentiation, i.e. computing the difference between sample values and then looking for the zero-crossing points in the differentiated data. Armed with the positions and amplitudes of the peaks, we can take the average and easily obtain the amplitude and frequency.  Notice that any DC offsets and low-frequency baseline wander will be removed via the differentiation operation.

This is just a simple example of how to extract the properties of a sinusoid in real-time using science and mathematics and an understanding of the underlying process without the need for ML training data.

AIoT feature extraction smart sensor design workflow

Arm’s Synchronous Data Stream (SDS) Framework provides developers with an easy method of capturing and playing back real-time sensor data for embedded AIoT sensor applications on Arm Cortex-M processors. A set of Python utility scripts are available for recording, playback, visualisation and data conversion, where the latter supports the conversion of captured SDS data files into a single CSV file – providing a simple bridge between the ASN Filter Designer and the SDS Framework.

An AIoT smart sensor design workflow using the ASN Filter Designer and the SDS Framework is shown below.

As seen above, three major components constitute the AIoT design workflow.

  1. Arm SDS Framework: capturing IoT sensor data and converting it to CSV format.
  2. ASN Filter Designer: importing the CSV datafile and then analysing the data. Based on the data analysis, a suitable filter can be designed together with other filters and IP blocks in order to build feature extraction algorithms for ML applications.
  3. Application deployment: Generating optimised C code and combining the design with an application for use on an Arm microcontroller.

The SDS Framework can be used with all major demo boards, including ST’s Discovery kit and Nucleo boards. SDS Python utilities are used to convert the captured *.sds and *.yaml files into a CSV file for import into the ASN Filter Designer, as discussed in the following section.

Data Import Wizard

The ASN Filter Designer’s comprehensive data import wizard can delimitate and import a variety of multi-column IoT datasets in CSV or TXT form.

As seen in the video, a generated CSV file can be dragged and dropped onto the signal analyser canvas, bringing up the data import wizard. The import wizard will automatically check the imported data for errors (such as NaNs, Infs etc) and then order the data into columns. Any header line data can be skipped by setting the Skip Headerlines value respectively.

For the example considered herein, the data is actually triaxial accelerometer data (i.e. X, Y and Z axes) with an extra column for the timebase. Therefore, if we wish to import the X-axis data, we can simply click on the header for the second column (B).   The tool will then ask you to recheck the data, and upon clicking on ‘Save’ will save the selected data as a single-column CSV file (needed for the ASN Filter Designer). This new CSV file can then be streamed via the tool’s signal generator for algorithm development.

Deploying to Arm Cortex-M processors

After completing the design process, the designed filter(s) can be deployed to STM32CubeIDE or Arm/Keil uVision for integration into an application project. Depending on the functionality of the ASN Filter Designer’s signal chain, two software frameworks are available: Arm’s CMSIS-DSP and ASN’s ANSI C DSP.

The ANSI C DSP framework was developed with close collaboration with Arm’s architecture team, providing outstanding computational performance and is required for real or complex coefficient floating-point designs that use multiple filters and mathematical functions in a signal chain. The Arm CMSIS-DSP framework on the other hand is an excellent choice for implementing both fixed-point and floating-point filters, but is limited to real coefficient single FIR filter or one IIR Biquad cascade with no extra mathematical functions.

A benchmark comparison for both frameworks is shown below for an 8th IIR filter running on three different Arm cores. As seen, the ASN Framework is slightly faster (lower means better performance) than the Arm Framework.

Framework Benchmarks: lower number of clock cycles means higher performance.

Arm CMSIS-DSP wizard

Professional licence users may expedite the deployment by using the Arm deployment wizard. The tool will automatically analyse your design and choose a suitable Framework. If the design cannot be exported via the Arm CMSIS-DSP framework, the tool will suggest that you use the ASN ANSI C framework and launch the code generation wizard.

Note that the built-in AI will automatically determine the best settings for your design based on the quantisation settings chosen.

Clicking on Deploy will automatically analyse your complete filter cascade and convert any extra filters in the cascade into an H1 (primary) for implementation. Upon completion, the tool will then launch the C code generation wizard.

CMSIS-DSP C code generation

Depending on which C framework is used, the C code generator wizard will automatically generate the C code needed for your design. For developers using the Arm CMSIS-DSP framework, a single C file is generated for use with an MDK5 software pack. The MDK5 pack is available from Arm Keil’s software pack repository, providing several complete filtering examples based on the ASN Filter Designer’s code generator using the Arm CMSIS-DSP library.

A detailed help tutorial is available by clicking on the Show me button. 

ASN ANSI C DSP code generation

For developers using the ASN ANSI C DSP framework, the code wizard should be used.

NB. The wizard will produce a CodeBlocks project in order to get you started. The following section describes in detail the steps needed for using the generated code in a STM32CUBE-IDE project. Please refer to the ANSI C SDK user guide for step-by-step instructions on how to use the generated code in other IDEs. 

A PDF version of this article is available as an application note.

Author

  • Dr. Sanjeev Sarpal

    Sanjeev is an AIoT visionary and expert in signals and systems with a track record of successfully developing over 25 commercial products. He advises top international blue chip companies on their AIoT solutions and strategies for I4.0, telemedicine, smart healthcare, smart grids and smart buildings.

Over the decades Microsoft has produced various programming languages (e.g. C#, F#, Visual Basic) and flavours of their .NET paradigm, such as the very popular 4.x .NET Framework.  

C# is very popular among Windows developers, as it is based on objected orientated programming concepts together with a few other pearls, such as automatic memory management (something that had to be handled manually in C++), in an attempt to provide many of the advantages of C++ in a much more simplified way.

These pros combined with the .NET Framework’s extensive charting library, UI toolbox, Networking, ML engine libraries and general ease of use in Microsoft Visual Studio was one of the primary reasons that many Windows-based scientific programs (e.g. ASN Filter Designer) were developed using the C# language and .NET Framework.

Over the last few years, Microsoft has tried to consolidate their .NET solution into a single, fast, cross-platform solution with the advent of the .NET Core paradigm. .NET Core is an open-source framework for developing Windows, web applications, services, and mobile applications and it can be run on Windows, Mac and Linux. Microsoft contends that .NET Core is much faster than the .NET Framework since the architecture has been completely rewritten to make it modular, lightweight, fast and cross-platform compatible.

DSP filtering library for C# .NET applications

For many modern scientific applications digital filtering of datasets is just one of the many components needed for an algorithm. This could be extracting ECG and PPG biomedical features, cancelling powerline interference or removing the noise from a dataset. In many cases, it is desirable to perform the filtering in real-time on streaming data as part of an algorithm updating dashboard analytics.

ASN Filter Designer provides .NET developers with an automatic code generator and SDK for developing high-performance data filtering applications in C#.

The tool’s project wizard bundles all of the necessary SDK framework files needed to run a designed filter cascade without the need for any other dependencies or 3rd party plugins. The deployed code is fully compatible with Microsoft Visual Studio and all .NET versions.

A complete overview of the SDK is available here.

 

 

Download demo now

Licencing information

Author

  • Dr. Sanjeev Sarpal

    Sanjeev is an AIoT visionary and expert in signals and systems with a track record of successfully developing over 25 commercial products. He advises top international blue chip companies on their AIoT solutions and strategies for I4.0, telemedicine, smart healthcare, smart grids and smart buildings.

Designs an FIR notch filter from a lowpass filter by computing the difference between the prototype lowpass filter and its amplitude complementary

ASN Filter Designer’s new ANSI C SDK framework, provides developers with a comprehensive automatic C code generator for microcontrollers and embedded platforms. This allows developers to directly deploy their AIoT filtering application from within the tool to any STM32, Arduino, ESP32, PIC32, Beagle Bone and other Arm, RISC-V, MIPS microcontrollers for direct use.

Arm’s CMSIS-DSP library vs. ASN’s C SDK Framework

Thanks to our close collaboration with Arm’s architecture team, our new ultra-compact, highly optimised ANSI C based framework provides outstanding performance compared to other commercial DSP libraries, including Arm’s optimised CMSIS-DSP library.

Benchmarks for STM32: M3, M4F and M7F microcontrollers running an 8th order IIR biquad lowpass filter for 1024 samples

As seen, using o1 complier optimisation, our framework is able to surpass Arm’s CMSIS-DSP library’s performance on an M4F and M7F. Although notice that performance of both libraries is worse on the Cortex-M3, as it doesn’t have an FPU. Despite the difference, both libraries perform equally well, but the ASN DSP library has the added advantage of extra functionality and being platform agnostic, making it ideal for variety of biomedical (ECG, EMG, PPG), audio (sound effects, equalisers) , IoT (temperature, gas, pressure) and I4.0 (flow measurement, vibration analysis, CbM) applications.

AIoT applications designed on the newer Cortex-M33F and Cortex-M55F cores can also take advantage of extra filtering blocks, double precision arithmetic support, providing a simple way of implementing high performance AI on the Edge applications within hours.

Advantages for developers

  • A developer can now develop, test and deploy a complete DSP filtering application within the ASN Filter Designer within a few hours. This is very different from a traditional R&D approach that assigns a team of developers for several days in order to achieve the same level of accuracy required for the application.
  • Open source and agnostic code base: In order to allow developers to get the maximum performance for their applications, the ASN-DSP SDK is provided as open source and is written in ANSI C. This means that any embedded processor and any level of compiler optimisation can be used.
  • Memory size required for the ASN-DSP SDK is relativity lower than other standard DSP libraries, which makes the ASN-DSP SDK extremely suitable for microcontrollers that have memory constrains.
  • Using the ASN Filter Designer’s signal analyser tool, developers now can test the performance, accuracy and assess the frequency response of their designed filter and get optimised C code which they can directly use in their application.
  • The SDK also supports some extra filtering functions, such as: a median filter, a moving average filter, all-pass, single section IIR filters, a TKEO biomedical filter, and various non-linear functions, including RMS, Abs, Log and Sqrt.  These functions form the filter cascade within the tool, and can be used to build signal processing applications, such as EMG and ECG biomedical applications.
  • The ASN-DSP SDK supports both single and double precision floating point arithmetic, providing excellent numerical accuracy and wide dynamic range. The library is unique in the sense that it supports double precision arithmetic, which although is not the most optimal for microcontrollers, allows for the implementation of high-fidelity filtering applications.

The ANSI C SDK framework is further extended by our new C# .NET framework, allowing .NET developers to build high performance desktop applications with signal processing capabilities.

Find out more and try it yourself

Benchmarks on a variety of 32-bit embedded platforms, including a biomedical EMG filtering example, are covered in the following application note.

The both framework SDKs are available in ASNFD v5.0, which may be downloaded here.

Many Audio/acoustics engineers and researchers and audio hobbyists work with DSP (Digital Signal Processing). Some now and then, some on daily basis. Working on DSP for audio and speech, common challenges to create digital filters are: Noise cancellation, due to interference and Audio and Speech enhancement. And for whom DSP is not his daily job: filter design in general. In this blog, you’ll find out how the ASN Filter Designer may help for both experienced audio engineers and engineers where DSP is not their daily job to create digital filters for audio and speech.

For whom? For those with some and experienced DSP knowledge alike

If you are a audio/acoustics engineer or researcher or hobbyist: ASN Filter Designer is tailored for whom DSP is not his daily job and with some knowledge DSP. For those who need filter design and have to create some signal analysis. But also for those whom DSP is his daily job and want to save time and money. Most engineers who are working with DSP on a daily basis, are usually working with extensive but also expensive tools. Or want to do the maths themselves. Also for them ASN Filter Designer is useful:

  • Intuitive and easy to use.
  • Save days of time spending calculating on your own for the price of 2-3 hours of work.
  • Few lesser costs then extensive tooling with features you don’t use anyway.
  • Automatic code generation: export for further analysis to Matlab, etc, or to Cortex-M Arm based processors via the Arm CMSIS-DSP software framework.

How DSP for Speech and audio benefit from ASN Filter Designer:

  • Experiment with a variety of equalisation, noise cancellation and sound effect audio filtering algorithms.
  • Perform data analysis in the frequency domain and via specialised methods, including Cepstral analysis on the streaming data.
  • Import your own wav audio files (mono or stereo up to 48kHz) for streaming, and modify the filter characteristics in real-time while listening to the filtered audio stream.

Some features for creating digital filters for Audio and Speech:


The sampling frequency may be specified up to 4 decimal places

Sampling frequency

which is useful for designing filters based on fractional sampling frequencies, such as multiples of the 44.1kHz audio standard. Common examples include audio interpolation filters: 44.1kHz × 128 = 5.6448MHz and 44.1kHz × 256 = 11.2896MHz.

Filter orders of up to 499

may be constructed, where this is limited to 200 for streaming audio applications. As with the IIR filters, a FIR’s zeros may be modified by the P-Z editor (Method dropdown list changes to User defined), including the ability of adding poles and converting it into an IIR filter.

Audio and user data playback streaming

Signal Generator Controller: 
Choose what you want to listen to; Adjust the amplitude of the input signal
Signal Generator Controller:
Choose what you want to listen to; Adjust the amplitude of the input signal

The signal analyzer allows designers to test their design on audio, real (user) data or synthetic data via the built-in signal generator. Default data playback is implemented as streaming data, providing a simple way of assessing the filter’s dynamic performance, which is especially useful for fixed point implementations. Both frequency domain and time domain charts are fully supported, allowing for design verification via transfer function estimation using the cross and power spectral density functions. As with all other charts, the signal analyzer chart fully supports advanced zooming and panning, as well as comprehensive chart data file export options.

Load .wav for playback

The signal generator allows you to load .wav audio files for playback via the Audio File method. Both mono and stereo formats are fully supported for 8.000, 11.025, 16.000, 22.05, 44.1 and 48kHz. sampling rates. There is no restriction as to the length of the .wav file.

You may add extra signals to input audio stream

Use the signal generator to add sinewaves and white noise to the data stream.

Intuitive data analysis with the mouse

Move the mouse over the chart will automatically produce data markers and data analytics (shown at the bottom right side of the GUI). The signal analyzer is directly coupled to the filter designer GUI. This means that you may modify the filter characteristics, and see the effects in real-time in the signal analyzer. This functionality is very useful when designing audio filters, as the new filter settings can be heard immediately on the streaming audio feed.

Digital filters commonly used in audio and speech

speech and audio engineer researcher working on DSP digital filters microphone headphone

The ASN Filter designer includes digital filters commonly used in audio such as:

Read review here:

Top marks from Jacob Beningo

UI experience 2020 pack

Na het downloaden van de ASN Filter Designer willen de meeste mensen gewoon met de tool spelen, om een gevoel te krijgen of het voor hen werkt. Maar hoe ga je aan de slag met de ASN Filter Designer? Op basis van goede gebruikersfeedback wordt ASNFD v4.4 nu geleverd met het UI experience 2020-pakket. Dit pakket bevat gedetailleerde coachingstips, een verbeterde gebruikerservaring en stap-voor-stap instructies om je op weg te helpen met je ontwerp.

Een snel overzicht van de ASN Filter Designer v4.4 vindt je hieronder, een geweldige tool voorDSP IIR/FIR digitaal filterdesign!

De ASN Filter Designer heeft een snelle, intuïtieve gebruikersinterface. Ontwerp interactief, valideer en implementeer jouw uw digitale filter binnen enkele minuten in plaats van uren. Het kan echter moeilijk zijn om een eerste begin te maken met DSP-filterontwerp, vooral wanneer je geen diepgaande kennis hebt van digitale signaalverwerking. De meeste mensen willen gewoon experimenteren met een tool om een gevoel te krijgen of het voor hen werkt (ja, natuurlijk zijn er tutorials en video’s). Maar waar begin je dan?

Start onmiddellijk met experimenteren met het filterontwerp

Daarom hebben we het UI Experience 2020-pakket ontwikkeld. Op basis van de feedback van de gebruikers hebben we gedetailleerde tooltips en animaties van de belangrijkste functionaliteiten gemaakt. Binnen enkele minuten krijgt u een kickstart in functionaliteiten zoals chart zoom, panning en design markers.

This image has an empty alt attribute; its file name is methods_TP-3.png

Coachingstips, verbeterde gebruikerservaring, stap-voor-stap instructies

Gebaseerd op de feedback van de gebruiker bevat het UI Experience 2020-pakket:

  • Uitgebreide coachingtips
  • Gedetailleerde uitleg over ontwerpmethoden en soorten filters
  • Verbeterde gebruikerservaring:
    • cursors
    • animaties
    • visuele effecten
  • Links naar gedetailleerde werkende oplossingen, tutorials en stap-voor-stap instructies
This image has an empty alt attribute; its file name is Coaching-Tip3.png
This image has an empty alt attribute; its file name is Information-FD3.png

De feedback van de gebruikersgemeenschap is zeer positief! Door het verstrekken van gedetailleerde tooltips en animaties van de belangrijkste functionaliteit, is de eerste stap van het ontwerpen van een filter met jouw gewenste specificaties aanzienlijk vereenvoudigd.

Begin dus meteen met de ASN Filterontwerper en bespaar tot 75% op jouw ontwikkelingskosten!

ASN Filter Designer box
ASN Filter Designer box, the powerful DSP Filter Designer platform

DSP voor ingenieurs: de ASN Filter Designer is de ideale tool om de sensordata snel te analyseren en te filteren. Maak een algoritme binnen enkele uren in plaats van dagen. Wanneer u met sensorgegevens werkt, herkent u deze uitdagingen waarschijnlijk:

  • Mijn sensordatasignalen zijn te zwak om zelfs maar een analyse te maken. Daarom heb ik versterking van de signalen nodig
  • Waar ik een vlakke lijn zou verwachten, zien de gegevens eruit als een puinhoop door interferentie en andere vervuiling. Ik moet de gegevens eerst opschonen voordat ik ze analyseer.
Sensor data: wanted components, desired signals (DC components), and unwanted components (50HZ sine powerline interference, white noise). Filter sensor data DSP

Waarschijnlijk heb je tot nu toe dagen of zelfs weken gewerkt aan signaalanalyse en filtering. Het ontwikkelingstraject is over het algemeen langzaam en zeer pijnlijk. Denk maar eens aan het aantal uren dat je had kunnen besparen als je een ontwerptool had gehad die alle algoritmische details voor jou beheerde. ASN Filter Designer is een standaardoplossing voor de industrie die wordt gebruikt door duizenden professionele ontwikkelaars die wereldwijd aan iot-projecten werken.

Onze nauwe samenwerking met Arm en ST zorgt ervoor dat alle ontworpen filters 100% compatibel zijn met alle Arm Cortex-M processoren, zoals de populaire STM32-familie van ST.

Uitdagingen voor ingenieurs

  • 90% van IoT smart sensors zijn gebaseerd op Arm Cortex-M processor technologie
  • Sensor signal processing is moeilijk
  • Sensoren hebben moeite met interferentie en allerlei ongewenste componenten
  • Hoe ontwerp ik een filter dat voldoet aan mijn requirements?
  • Hoe kan ik mijn ontworpen filter controleren op testdata?
  • Voor betere product performance is schone sensor data nodig
  • Tijdrovend proces om een filter op een embedded processor te implementeren
  • Tijd is geld!

Ontwerpers verzanden vaak met traditionele tooling. Deze vereist meestal een iteratieve, trial and error aanpak of deskundige kennis. Met deze aanpak gaat kostbare tijd verloren. ASN Filter Designer helpt u met een interactieve ontwerpmethode. Hierbij voert de tool automatisch de technische specificaties in op basis van eisen die de gebruiker grafisch heeft ingevoerd.

Snelle ontwikkeling van het DSP-algoritme

  • Volledig gevalideerd filterontwerp: geschikt voor toepassing in DSP, Arm microcontroller, FPGA, ASIC of PC-toepassing
  • Automatische gedetailleerde ontwerpdocumentatie: de Filter Designer helpt je met documenatie, waardoor je de peer review kunt versnellen en projectrisico’s verlaagt
  • Eenvoudige overdracht: projectdossier, documentatie en testresultaten bieden een gemakkelijk manier voor overdracht aan collega’s of andere teams
  • Gemakkelijk in te passen in nieuwe scenario’s: het ontwerp kan eenvoudig worden aangepast aan andere eisen en scenario’s, zoals 60Hz interferentieonderdrukking op de voedingslijn, in plaats van de Europese 50Hz.

ASN Filter Designer: de snelle en intuitieve filter designer

De ASN Filter Designer is het ideale hulpmiddel om sensorgegevens snel te analyseren en filteren. Indien nodig kun je jouw gegevens eenvoudig naar tools als Matlab en Python exporteren voor verdere analyse. Daarom is het ideaal voor ingenieurs die een krachtige tool voor signaalanalyse nodig hebben en een datafilter voor hun IOT-toepassing moeten maken. Zeker als je af en toe een datafilter moet maken. Vergeleken met andere tools creeer je een algoritme binnen enkele uren in plaats van dagen.

Exporteer jouw algoritmes naar Matlab, Python of een Arm microcontroller

Je kunt veel tijd besparen doordat je met ASN Filter Designer algoritmes eenvoudig kunt implementeren in Matlab, Python of direct op een Arm-microcontroller omdat de Filter Designer automatisch code generateert.

Onmiddelijke verlichting

Denk eens aan het aantal uren dat je had kunnen besparen als je een ontwerptool had gehad die alle algoritmische details voor je beheerde.

ASN Filter Designer is een standaardoplossing in de sector die wordt gebruikt door duizenden professionele ontwikkelaars die wereldwijd aan ivd-projecten werken. Onze nauwe samenwerking met Arm en ST zorgt ervoor dat alle filters 100% compatibel zijn met alle Arm Cortex-M processoren.

Hoeveel pijnverzachting kun je voor 145 Euro kopen?

Omdat veel technici onze ASN Filterontwerper voor korte tijd nodig hebben, is een licentie van 145 euro voor slechts 3 maanden mogelijk!

Vraag jezelf maar af: is 145 Euro een eerlijke prijs om te betalen voor onmiddellijke pijnverlichting en resultaat? Wij denken van wel. Bovendien hebben we een licentie voor 1 jaar en zelfs een eeuwigdurende licentie. Download de demo om het zelf te zien of neem contact met ons op voor meer informatie

 

 

Download demo

Prijzen en licenties

Chebyshev I and Chebyshev II filters: what are the advantages and disadvantages? And what is the syntax of Chebyshev, explained with ASN Filterscript

What are Finite Impulse Respsonse (FIR) Filters? And how to design FIR Filters in ASN Filter Designer and which filters does ASN Filter Designer support?