Alin Mazare

Detecting errors in digital communications with CRC codes implemented with FPGA

Generally speaking, cyclic redundancy checks (CRCs) are used to detect errors from noise in digital data transmission. The technique is also sometimes applied to data storage devices, such as a disk drive. They also have been turned to verify the integrity of files in a system in order to prevent tampering and suggested as a possible algorithm for manipulation detection codes. It has been known that a CRC will not detect all errors but with random noise it is unlikely. In this paper, we present an efficient algorithm for parallel computation of the CRC in data transmission.

Fully integrated artificial intelligence solution for real time route tracking

In this paper the authors propose a solution in which an intelligent algorithm - genetic algorithm in our case - is used to generate commands for a robot in real time, so that the robot can determine the optimal moves considering several aspects: route tracking and low power consumption. Genetic algorithms are intelligent solutions for multi-criteria optimization and using them to find solutions to the optimization problems containing constrictions. However, they were designed as algorithms running on computer and therefore cannot ensure rapid generation of the solutions. On the other hand, the problem of determining the optimal response to command a robot requires real time response. The paper presents a method for hardware implementation and integration in a FPGA circuit of a genetic algorithm, in order to accelerate the convergence and to generate solutions in real time.

Error detection and correction using LDPC in parallel Hopfield networks

Low Density Parity Check (LDPC) coding is a classical method for the detection and correction of errors. Its problem is the relatively complex operations which must be performed at encoding, and especially at decoding, to detect and correct errors caused by communication channels. We present a solution for the errors correction using regular LDPC and Hopfield network-based associative memories. Our solution solves this problem by using an associative memory based on the Hopfield network on the decoding stage, which stores the correct code words. This memory tends to transform the code words received with errors in errors free code words. We improved the ability of the associative memory by storing the code words in a specific format (pairs with their inverses, the constant number of “1” bits). These conditions are met by using LDPC coding. To be viable in communications, which require real-time correction, our proposed solution has used Hopfield networks operating in parallel, fully integrated into the Field Programmable Gates Array (FPGA) circuit.

VLSI implementation of an associative content addressable memory based on Hopfield network model

The content addressable memory (CAM) is allowed to search a data word without knowing where its address is. In addition, it is permissible to associate the content of the location or neighboring locations where the data word was identified. This paper presents our own approach for VLSI hardware implementation of the CAM memory. The proposed solution uses a Hopfield neural network model and is characterized by simplicity and the possibility of using the same hardware structures for saving may data patterns. Will be presented design methods and implementation to VLSI circuit structures, the performance of our solution and experimental results.

Experimental module for assistive technologies applications

This paper approaches the problem of implementing an experimental module that facilitates the teaching and learning of the Braille alphabet. The proposed system follows to improve the existing assistive technologies dedicated for helping visually impaired peoples. The main board of the experimental module is realized around the PIC 16F877A microcontroller that runs a proprietary software application for controlling the operation of the system. A set of two stepper motors and six solenoids are used for actually emboss the Braille characters on the paper or other suitable physical support. For ensuring the required level of power, the solenoids and the stepper motors are connected to the output ports of the microcontroller trough a set of drivers realized with ULN2803A circuits. The module can communicate with a PC through a serial interface. This connection is necessary for receiving the characters that mast be printed. The conversion of the plain text to the Braille format, together with other formatting steps are realized in an automate manner by the software processing application installed on the PC. The maximum printing speed achieved with the proposed module is of 50 characters/second approximately. By using a compact hardware architecture based on microcontrollers combined with a versatile software program, dedicated for this type of application, the proposed module distinguish by other existing implementations through its reliability and flexibility in operation.

Real time system for instrumental sound extraction and recognition

This article presents a “smart sound sensor” solution. More specifically it is a system on a chip capable of extracting sound patterns from an input signal captured by a microphone, patterns that correspond to certain musical instruments. The aim is to identify sounds like: voices, ambient sounds or musical sounds. Such applications generally involve the presence of a computer that analyzes offline the audio sequence. There are also smartphone security applications that rely on voice recognition templates that were previously stored and which work by processing the input sequence offline, after recording. Unlike these methods, our solution enables online real time identification of a group of musical instruments and allows extracting of certain sound sequences that belong to a particular instrument so that it can be isolated for sole playing. The solution was implemented in an integrated system “sound sensor” that analyzes the input signal in real time and can give output data without additional elements.

Real time system for image acquisition and pattern recognition using Boolean neural network

The system presented in this paper consists of an image acquisition module from a video camera, an image processing module, which performs conversion to monochrome format, and a neural network that takes the acquired images and performs the extraction of patterns from them. The system proposed by the authors is used for recognizing the orientation of objects in real time by analyzing images from a common video camera. The acquisition module is based on three high-speed AD converters. The remaining components: the digital image processor and the neural network used to classify the shapes of objects are both integrated into a FPGA circuit. All these ensure integration in one chip and a high speed response - typical requirements for a real-time system.

Indoor Broadcasting System for Personalized TV Emissions Addressed to Tele-Assisted Persons

Abstract The category of peoples that need tele-assistance includes persons with special needs (i.e. elderly, chronics, etc.) whose life style should be monitored and guided according to personalized plans. In this paper we propose a system for remote control of the TV-sets in a residence so that they become able to receive and display some thematic programs running on an embedded PC, which is generally placed into other room. The system includes two parts: one is dedicated to control remotely the TV-set and other is to transmit the film from PC to TV. A key issue to solve was to assure the remote control of the TV-set by PC without user action involving and also avoiding any modification inside the existent equipments. The proposed solution is based on a special designed relay-translator which manages a radio receiver module and an IR transceiver.

Microcontroller based thermal enclosure for electronic boards testing

In this paper is presented a new approach for implementing a versatile temperature control and monitoring system for thermal enclosures based on Peltier thermoelectric elements. The system is intended to be used for temperature testing of equipped or unequipped electronic printed circuit boards (PCB). These types of tests regarding thermal aging and endurance are very important for verifying the long term reliability of the PCBs because they must be designed for different categories of applications which impose certain operational time periods in various thermal conditions. The control module of the thermal enclosure described in this paper is realized with PIC16F877 microcontroller that communicates through serial interface with a dedicated software application running on PC. The functional parameters of the system can be monitored either on a local LCD or on PCs display. The testing procedures can be configured only from the software application. The power of the heating and cooling elements is around 36Wallowing an effective temperature control in the range [−15-100] °C. Compared with classical implementations, the design using Peltier elements has the important advantage of been capable to operate within a wide range of temperatures, including negative values, which allows more accurate tests and a realistic characterization of the electronic boards.

Electricity consumption measurement system for detecting losses occurring in power transmission networks

The paper proposes a solution for measuring the current consumption on the transmission lines for detecting the losses that may occur. The solution is non-invasive: the sensors determine the current by analyzing the electric field around the isolated conductor, it is fully mobile and easy to install: sensors are “clamp” type and can be placed on insulated conductors, data is transmitted wirelessly to a local collector that will then transmit it to the server — no installation infrastructure is needed. The solution is also energy-efficient: the sensors and the data transmitter feed from the electric field around the conductor (self-harvesting sensors) while the concentrator (the local data collector) is powered from batteries connected to a photovoltaic panel. The solution will provide data at a central server where it will be analyzed and compared to consumer data (e.g. from smart grid). The assessment of consumption on electricity transmission lines allows: to determine the losses occurring up to the customers current meters, to determine the profile of some consumers and to establish tariff plans according to them, to establish an optimal energy transmission plan from suppliers to consumers. Electricity consumption measurement, self harvesting sensors, non-invasive, wireless networks.