Onboard IIR Filters Enhance Data Acquisition
Bessel, Butterworth, Chebyshev, Elliptic
NEWS FOR IMMEDIATE RELEASE |
|---|
|
For more information, contact |
Bellevue, WA, May 31, 2001 -- Microstar Laboratories, Inc., maker of Data Acquisition Processor (DAP) boards, today announced an IIR filter module: an onboard digital implementation of the five classic filter types: Bessel, Butterworth, Chebyshev, Inverse Chebyshev, and Elliptic. The new product, DAPL IFM (IIR Filter Module), forms an optional additional command module to DAPL 2000: a 32-bit multitasking real-time operating system that runs on every DAP board. A user normally controls DAPL 2000 through Windows (NT, 2000, ME, 98, 95), either locally or over a network. Every standard DAP model in current production also will run under Linux.
DAPL 2000 makes it easy to configure a DAP board for high-performance applications under Windows or Linux. The onboard operating system supports over 100 easy-to-use commands optimized for data acquisition and control. A complete application can require as few as six or seven commands out of the many available. Command categories include
- DSP -- Filtering
- DSP -- Spectral Analysis
- Sensor Conditioning
- Software Triggering
- Process Control
To browse the complete command list visit Microstar Laboratories: DAPL Command Summary.
The new DAPL IFM command module extends the range of DAPL 2000 by giving a user a simple means to specify onboard IIR filters that run in real time and continuously filter the sampled data stream. A single command, named for the filter type, specifies the filter in just one line:
CHEBYSHEV(IPIPE0, 8, 0.20, 0.1, $BINOUT)
The above command operates on the data stream from channel 0 (input pipe 0); it applies an eighth-order Chebyshev filter, with a cutoff at 20% of the Nyquist frequency (Nyquist frequency = half of the sample rate) and allows a 0.1 decibel passband ripple. It streams the filtered data to the PC through the system binary output pipe, $BINOUT.
The four other commands, BUTTERWORTH, BESSEL, CHEBYINV, ELLIPTIC, for the four other filter types, have the same simple user interface: source, order, cutoff, ripple levels, and destination. Any data pipe, not just those shown, may act as source or destination.
A single DAP board, with external rack-mounted expansion hardware, can handle up to 512 analog inputs. With the new DAPL IFM (IIR Filter Module), DAPL 2000 now can filter the data on any channels using any mix of these filter types. The filters operate independently, and each filter may have different parameters. The new IIR filters complement the existing FIR filters built into DAPL 2000.
Microstar Laboratories includes DAPL IFM in the DAPtools Standard software package. Contact us to order.
# # #
Editorial Overview:
Microstar Laboratories, Inc., maker of Data Acquisition Processor boards, today announced an IIR filter module, an onboard digital implementation of the five classic filter types: Butterworth, Bessel, Chebyshev, Inverse Chebyshev, and Elliptic. DAPL IFM (IIR Filter Module) extends DAPL 2000: a 32-bit multitasking real-time operating system with 100+ built-in commands optimized for data acquisition and control. A user normally controls DAPL 2000 through Mdows (NT, 2000, ME, 98, 95), either locally or over a network. (The boards also have Linux drivers.) DAPL 2000 makes it easy to implement a high-performance application, and, with DAPL IFM, now lets users specify -- in software -- familiar filters that continuously filter the acquired data stream. To find out more, click on New in the sidebar. Or talk to the people at Microstar Laboratories.
Note to the Editor:
Microstar Laboratories illustrates this text with the following images: 1) Output from the CHEBYSHEV command in the text, superimposed on the input waveform; 2) FFT of the output in (1) superimposed on the FFT of the input, showing high frequency attenuation.
Microstar Laboratories, Inc. claims Microstar Laboratories, Data Acquisition Processor, DAP, and DAPL as trademarks.
Microsoft Corporation has registered Microsoft, Windows, Windows 95, Windows 98, Windows ME, Windows 2000, and Windows NT as trademarks. The term "Linux" is a registered trademark of Linus Torvalds, the original author of the Linux kernel. Other product names may be trademarks of their respective companies.
Microstar Laboratories makes it a practice to use an appropriate symbol at the first occurrence of a trademark or registered trademark name in a document, or to include trademark statements like this with the document.