Заглавие:Design and analysis of symmetrical spiral inductors for RFIC
Автор:Petkov, Ivan V.; Pukneva, Diana I.; Hristov, Marin H.Дата:2006Резюме:In this paper are discussed symmetrical inductors. They have significant advantages over classical 2-port inductors in silicon-based RFIC, e.g. higher Q factor, higher self-resonant frequency, and smaller inductor size. 2-port classic and 3-port symmetrical inductors with different electrical parameters and sizes are simulated and compared.Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Implementation of an IGBT behavioral model in matlab/simulink
Автор:Asparuhova, Katya Konstantinova; Terzieva, Snegana Dimitrova; Grigorova, Tsvetana GrigorovaДата:2006Резюме:The paper presents implementation of an IGBT behavioral model in MATLAB/Simulink. The model is built using the configuration of the Hammerstein model consisting of a nonlinear static block followed by a linear dynamic block. The nonlinear DC equations and correction functions are precisely represented and the parameters of the dynamic part ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Analysis of two new approaches for noise reduction in us images
Автор:Georgieva, Veska; Георгиева, ВескаДата:2006Резюме:In the paper was presented а comparative analysis of two new approaches for specific noise reduction in medical ultrasound (US) images on the base of 2D Discrete Wavelet and Wavelet Packet Transformations. Some parameters of the wavelet transformations are optimized with the goal to become maximal noise reduction and improve the quality of ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Fifth-order lowpass sc ladder filter with reduced sensitivity to operational amplifiers finite gain and offset voltage
Автор:Radev, Nikolay Asenov; Ivanov, Kantcho PanayotovДата:2006Резюме:A combined approach for reducing the effects of operational amplifiers finite DC gain and offset voltage in fifth-order lowpass SC ladder filter is proposed. The filter with gain- and offset-compensated integrators and modified capacitance values yields significant improvement in the passband response.Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Mosfet simulation using matlab implementation of the EKV model
Автор:Angelov, George Vasilev; Asparuhova, Katya KonstantinovaДата:2006Резюме:The paper presents an implementation of EKV MOST model in Matlab environment. Parameter extraction and fitting procedures are briefly sketched.Open source modules for transistor characteristics and additional functions for parameter extraction and fitting are included in a Matlab toolbox. Model parameters are user defined to provide flexibility ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Parameterized tolerance models of switched-capacitor circuits
Автор:Gadjeva, Elissaveta Dimitrova; Garmev, Zdravko AtanasovДата:2006Резюме:In the present paper, parameterized models are developed for tolerance analysis of SC-circuits using standard PSpice-like circuit simulators. They allow the assessment of the design component tolerances using Monte Carlo and Worst Case analyses. The tolerance models of the capacitor and operational amplifier are based on multiphase models ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Behavioral modeling and simulation of spiral inductors with ansoft simplorer
Автор:Gadjeva, Elissaveta Dimitrova; Durev, Vladislav PetrovДата:2006Резюме:A behavioral model of spiral inductor is developed in the present paper realized using the possibilities of the Ansoft Simplorer simulator. The basic possibilities and advantages of Ansoft Simplorer for behavioral modeling and simulation of electronic circuits are presented. An example isnpresented illustrating the modeling and simulation ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Designing DSP algorithm with the virtex-4 xtremedsp slice
Автор:Kuncheva, Anna S.; Nikolov, Dimitar; Hristov, Marin HristovДата:2006Резюме:Finite impulse response (FIR) filter is the key functional block in DSP (Digital Signal Processing) designs and nearly always form the starting point for analyzing an architecture. This paper contains a new filter architecture, along with FPGA- Virtex-4 (Xilinx) and XtremeDSP (DSP48) slice. The XtremeDSP slice is a high performance multiplier ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Sigma-delta modulator prototyping using FPAA
Автор:Tzanov, Mihail Hristov; Manolov, Emil Dimitrov; Koparanov, Filip TodorovДата:2006Резюме:The paper presents the results from sigma-delta modulator prototyping. It briefly describes the classic structure of first and second order sigma-delta modulators. Three circuits of first order sigma-delta modulators and one circuit of a second order sigma-delta modulator were designed using Field Programmable Analog Array (FPAA). Their ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Design of FPAA sinewave oscillator based on Van der Paul equation
Автор:Koparanov, Filip Todorov; Manolov, Emil Dimitrov; Tzanov, Mihail HristovДата:2006Резюме:A Field Programmable Analog Array (FPAA) circuit of a low-frequency sinewave oscillator has been proposed and investigated in this paper. For that purpose the typical structure of a sinewave oscillator, based on the modeling of Van der Paul differential equation has been studied. Using the CAD system AnadigmDesigner2 the FPAA circuit of the ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Practical examination of relationships between design and performance parameters of CMOS amplifiers
Автор:Manolov, Emil Dimitrov; Hristov, Marin HristovДата:2006Резюме:The paper proposes a set of experiments with CMOS transistor array, which is a part of EDUCHIP test circuit. The goal of the experiments is to examine the dependence of the performance of CMOS amplifiers from bias current and W/L ratio of amplifying transistors. For that purpose different topologies of CMOS amplifying stages are presented ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Design and simulation testing of selective lc-amplifiers with active inductors
Автор:Pandiev, Ivailo Milanov; Donevska, Lila Andreeva; Stamenov, Dimitar IlievДата:2006Резюме:The present paper discusses the development of a specific type of selective LC amplifier with an active inductor and a current-feedback amplifier (CFA) with an additional port for control. The active inductor (gyrator) is built on the base of a general impedance converter (GIC), consisting of two op amps and RC-elements. The gyrator transforms ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:An enhanced simulation macromodel for current-feedback amplifiers
Автор:Pandiev, Ivailo MilanovДата:2006Резюме:In this paper, an enhanced SPICE macromodel for Current-Feedback Amplifiers
(CFA) is presented which takes into account the second-order effects such as the noise, the commonmode rejection ratio (CMRR), the positive and negative output voltage swing, and power-supply rejection ratio (PSRR) as a function of temperature. The simulation ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Systematical investigations of 137Cs concentration in soils in Bansko-Razlog region
Автор:Kostov, Lachezar K.; Костов, Лъчезар К.; Кобиларов, Румен Георгиев; Kobilarov, Rumen Georgiev; Костова, Любка Г.; Kostova, Lyubka G.; Младенов, Младен И.; Mladenov, Mladen I.; Протохристов, Христо Н.; Protohristov, Hristo N.; Стоянов, Чавдар П.; Stoyanov, Chavdar P.; Bachev, Simeon prew.; Бачев, Симеон рец.Дата:2005Резюме:Systematical investigations of Cs-137 concentration in soil in Bansko – Razlog region have been performed for the first time. A total area of about 40 km2 has been investigated. By means of high-resolution gamma-ray spectroscopy the radio-nuclide content of the soil samples has been determined. The Cs-137 deposition density following the ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Оптимизация на роторното потоксцепление при векторно управление на асинхронен двигател
Автор:Рац, Емил Роберт; Рац, Роберт Е.; Рачев, Емил; Rats, Emil Robert; Rats, Robert E.; Rachev, Emil; Михов, Михо Рачев рец.; Mihov, Miho Rachev prew.Дата:2005Резюме:The presented paper deals with the vector controlled induction motor drive behavior in case of taking into account the nonlinearity of motor inductance. The magnetizing current is
optimized in order to obtain the minimal stator current at given torque, which means that magnetizing flux is not constant.Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Алгоритми за изчисление на законите за регулиране на еднофазни колекторни двигатели при електронно управление
Автор:Божилов, Ганчо Йорданов; Иванова, Незабравка Ц.; Bozhilov, Gancho Yordanov; Ivanova, Nezabrazka Ts.; Ризов, Пламен рец.; Rizov, Plamen prew.Дата:2005Резюме:: In this paper are presented algorithms of calculation of the control laws of a single-phase commutator motor by electronic control. The single-phase commutator motors are nonlinear devices those can operate with alternative or direct current supply and by that mean the algorithms are developed about these two cases. For calculation of the ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Типови графики на яркостта в зоната на приближаване L20 на пътни тунели
Автор:Пачаманов, Ангел Саракинов; Прегьов, Борислав Г.; Pachamanov, Angel Sarakinov; Pregyov, Borislav G.; Василев, Николай рец.; Vasilev, Nikolay prew.Дата:2005Резюме:The main problem for design an energy efficient lighting systems of road tunnels is the choice of the maximum value for the luminance L20 in the access zone. To ease the design we have developed standard graphs of the yearly change of L20 for typical tunnel entrances and eight driving directions. Due to the small size of Bulgaria, the ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Алгоритъм и програма за изчисляване на адаптационната яркост при пътни и градски тунели
Автор:Караро, Улрих; Kararo, Ulrih; Прегьов, Борислав Г.; Pregyov, Borislav G.; Пачаманов, Ангел Саракинов; Pachamanov, Angel Sarakinov; Василев, Николай рец.; vasilev, Nikolay prew.Дата:2005Резюме:The main problem for design an energy efficient lighting systems of road tunnels
is the choice of the maximum value for the luminance L20 in the access zone. Method and computer program for calculating the annual chart of luminance L20 are presented in this paper. This chart is used for calculating the frequency and cumulative frequency ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Загуба на напрежение в линии на осветителна уредба, захранвана от инвертор
Автор:Пачаманов, Ангел Саракинов; Рац, Нели Симеонова; Иванов, Захари рец.; Pachamanov, Angel Sarakinov; Rats, Neli Simeonova; Ivanov, Zahari rew.Дата:2005Резюме:Inverters (AC-DC-AC) with frequency 50 - 130 Hz are used for dimming of lamps in street and tunnel lighting systems. Their output voltage has shape different from sinusoidal. The latter as well as the usage of discharge lamps leads to increasing the level of high harmonics of the current in the supply lines. The paper describes the method ...Библиотека:
TECHNICAL UNIVERSITY - SOFIA
Заглавие:Моделни изследвания на процесите в пещната камера на котли ПК-38-4
Автор:Бонев, Бончо Иванов; Тотев, Тотьо Иванов; Попова, Виктория Д.; Станков, Никола рец.; Bonev, Boncho Ivanov; Totev, Totyo Ivanov; Popova, Viktoriya D.; Stankov, Nikola rew.Дата:2005Резюме:The operation of the boilers type PK-38-4 in TPP “Maritza East 2” is connected with a lot of difficulties, mainly because of the combustion process. The base problem is the frequently ash deposits on the heating surfaces. Purposely discovering of the factors having influence on this negative phenomena, they are realized a great number of ...Библиотека: