Carptahian Journal of Electronic and Computer Engineering

4

Authors: J. Sütő, S. Oniga

This paper presents the implementation of a simulator application for feed forward neural networks which was made in Qt application framework. The paper demonstrates the object oriented design and the performance of the software. The main topics cover the class organization and some test results where the Matlab neural network toolbox was used as reference.

4

Authors: J. Tóth, Ľ. Ovseník, J. Turán

FSO technology is a progressive implementation of smart network solutions these days. The link speed, low cost, a fast implementation are just a few advantages of many other. Despite all those strengths there is at least one limitation. It is called weather. The wavelengths values on which FSO operates are quite similar to fog, smoke, snow and dust particles. It is obvious that if those proportions are comparable, it’s not surprising that there will be some interactions among beams and particles. That’s why we decided to investigate the weather influence to a link availability of FSO at our location in Kosice, Slovakia. To accomplish this we used fog sensor and wrote a simulating program for data processing. The industries as well as universities are already trying to solve the problems when FSO link is not working out because of low visibility. There is already the hybrid equipment on the market which serves as an additional component (an enhancement) by using RF (Radio Frequency) waves.

5

Authors: T. Harasthy, Ľ. Ovseník, J. Turán

Paper describes design of color filter for preprocessing of input plane for Traffic Sign Recognition System. Driver Assistance Systems (DAS) are nowadays very popular topic of info-electronic. One of the most often cited topic of DAS is Traffic Sign Recognition System. This system is usually based on edge detection, neural networks or invariant transform e.g. Trace Transform. In this article is color filter designed for traffic sign recognition system based on optical correlator. Optical correlator compares two images or two-dimensional data sets in very high speed. Usage of optical correlator request specific preprocessing of input scene, which is described in this paper. Color filtering is one of basic steps of preprocessing of input data (video) for Traffic Sign Recognition with usage Optical Correlator.

6

Authors: A. Buchman, C. Lung

Every WiFi, ZigBee or Bluetooth compatible radio chip provides a byte of information related to the received signal strength (RSS), the so called received signal strength index (RSSI). In a given point in space, on a specific radio channel, the RSS has a unique value at a given moment in time. Still, radio chips produced by different manufacturers will report different RSSI numbers. So RSSI is only related to, but not identical to RSS. In this paper, a formula that relates RSS and RSSI is derived. The validity of this theoretical assumption is tested on various vendors’ data. For Microchip’s MRF24WB radio chip the testing is done experimentally.

6

Authors: K. Lamár, A. G. Kocsis

The paper introduces the fundamentals of motor control. It explains the basic equations and introduces the control diagram of the brushed DC motor. It introduces the four quadrant DC chopper circuit and the basic methods to operate it. After that, it explains the fundamentals of the current control of DC motors and its two basic methods: the pulse width modulation and the hysteresis current control. Finally it gives a short example of the practical implementation of the hysteresis current controller for the four quadrant DC chopper in LabVIEW FPGA.