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Visilab Signal Technologies has a scientific background and lots of experience in industrial applications, both design and implementation. We don't do everything but do many. Mathematical modeling is not alien to us and we do some simulation too. We have made a number of inventions during the years, many of them implemented right into our products. Signal processing and phase-locked detection is close to us. We have made lots of struggle with the subject of superstable signal technology with significant progress. Back A member of IPC-onboard community Short explanation of terms and acronyms Embedded means self-consistent Embedded systems consist of a central processing unit (CPU), some memory for keeping its bootup code and possibly the rest of the programs too. Some systems download their actual programs after booting from some other computer. Typical for an embedded system is that it is able to operate correctly forever, restoring itself from any kind of disaster and malfunction as long as its CPU and memory are not damaged. Industrial systems usually have interfaces to real world, like analog-to digital converters (ADC), digital-to analog converters (DAC), logic signal input and output (I/O), keyboard and some sort of display (user interface). Many systems don't have user interfaces at all but operate completely independent. Their programs are repeating similar tasks forever. Some more developed systems are able to dynamically alter their behavior initiated by user or some other external event. Visilab Signal Technologies has developed a great number of systems with these features. We have also developed a process editor and a process controller in 1992. The user can program easily the system to contain several types on control structures dynamically set up with a varying number of simultaneous tasks and configurations. The tasks can be temperature ramps, chemical maturing processes, stepper motor drive patterns and various logic for I/O. This process editor/controller package has been redesigned several times for many differing systems. One can find versions of it in PAM2000 series of products, KLIMA etc. The amazing thing about this utility is that it can fit into a very small memory. E.g. for a simple 8-bit controller, the whole system requires typically some 24 kbytes, depending on the number of different tasks it can perform. DSP means Digital Signal Processing DSP is used in a great variety of technologies, from frequency analysis of oscillating systems to digital filtering of time series and detection of weak signals buried in noise using e.g. phase-locked technologies. Visilab Signal Technologies has put some effort into achieving technologies in all of these. For example, we have developed a new signal filtering method which does not restrict the band-pass. It just diminishes the amount of noise significantly. Multilayer Circuit Boards Multilayer circuit boards are used to have at least one ground plane (GP) and to facilitate routing of signals. The GP will act as a shield to prevent harmful electromagnetic interference radiating to the surroundings by fast acting logic circuits and microprocessors. This is necessary due to the EMC directive in the EU being widely adopted and required. The shield works in both ways, preventing external interference from entering sensitive electronics and causing harmful noise. This is valid locally too, as many components on the board will cause lots of interference to its surroundings by its fast current spikes. Visilab Signal Technologies has an excellent experience on how to use GP's to advantage to create low signal level circuits by using one or several copper layers. In most cases, a six-layered printed circuit board (PCB) is sufficient for signal routing and a GP, sometimes even a two-layered PCB. Putting CPU's and sensitive electronics on the same PCB is not a joke anymore but a sensible choice. However, a significant amount of experience is required to design successful systems in this way. Optical Systems and Total Design Visilab Signal Technologies has made several optical designs for customers' products, in addition to our own products. Many NIR and VIS solutions have been designed and are in active production. We are specialized in optical detectors and controlling of diffuse beams. Imaging systems are not alien to us either. A typical optical system architecture consists of a light source (a laser, LED, halogen lamp etc.), beam forming optics, a detector system (a phototransistor, photodiode, CCD, PbS, InGaAs etc.), beam collection optics, light choppers, filters, spectrometers, optical fibers and finally a total design integrating them all into a product. We have full capability of designing the required light controllers, preamplifiers, analog-to-digital converters and signal processors and system controllers needed. We can design also the PC program for Windows for data archiving and graphics etc. What we don't do at this time, is fieldbus master software and other time-consuming sw projects in the database world. We stick to what we know best. Tools in Use We have an optical CAD delivering 3D geometries, ray tracing, optimizing, CAD files etc. We have an electronic CAD which is a complete design system. Our high-quality 3D mechanical design software offers us a quick way to design requiring structures combining electronic boards and other components. We have a great number of cross compilers for various processors, emulators, logic analyzers etc. We also have excellent optical measuring devices targeted to our specialty areas. The most important tool is our experience, having been accumulated for a long time. Keywords: subcontracting, electronic design, printed circuit design, optomechanical design, optical design, phase-locked systems, low-noise signal detection, preamplifiers, optical sensors, intelligent sensors, fieldbus, Profibus DP, LabView programming, DSP, digital signal processing, single chip processors.