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Wyszukujesz frazę "Crest Factor" wg kryterium: Temat


Wyświetlanie 1-5 z 5
Tytuł:
Hardware Accelerated Simulation of Crest Factor Reduction Block for Mobile Telecommunications
Autorzy:
Nikodem, M.
Kępa, K.
Powiązania:
https://bibliotekanauki.pl/articles/226366.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
crest factor reduction
configurable hardware
hardware acceleration
FPGA
telecommunications
Opis:
This paper reports results of the hardware accelerated simulations of the crest factor reduction (CFR) block which is a common element of the radio signal processing path in base stations for mobile telecommunications. Presented approach increases productivity of radio system architects by shortening the time of model architecture evaluation. This enables unprecedented scale of CFR parameter optimization which requires thousands of simulation runs. We use FPGA device and Xilinx System Generator for DSP technology in order to model CFR block in MATLAB/Simulink environment, implement the accelerator and use it for mixed hardware-software simulation. Reported approach reduces simulation time by 70%, provides straight forward use of fixed-point arithmetic and lowers power consumption by 73% at the cost of constant and relatively low overhead on model development.
Źródło:
International Journal of Electronics and Telecommunications; 2012, 58, 4; 363-368
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DAC testing using impulse signals
Autorzy:
Vedral, J.
Fexa, P.
Powiązania:
https://bibliotekanauki.pl/articles/221597.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
DAC
ENOB
SINAD
FFT test
Crest Factor
Damped Sine Wave
SINC signal
Multi-Tone signal
Opis:
The Multi-Tone (MT) signal with uniform amplitudes can be used for DAC testing. This paper shows an easier way to generate a MT signal using several impulse signals. The article also analyzes qualities of methods for testing the dynamic parameters of Digital to Analog Converters using an impulse signal. The MT, Damped Sine Wave (DSW) and Sinx/x (SINC) signals will be used as the source for these tests. The Effective Number of Bits (ENOB) and Signal to noise and distortion (SINAD) are evaluated in the frequency domain and they are modified using the Crest Factor (CF) correction and compared with the standard results of the Sine Wave FFT test. The first advantage of the test using an impulse signal is that you need fewer input parameters to create the band signal for testing the DAC. The second one is to reduce the testing time using a band signal in comparison with multiple tests using a single sine wave.
Źródło:
Metrology and Measurement Systems; 2012, 19, 1; 105-114
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Suitable Spreading Sequences for Asynchronous MC-CDMA Systems
Autorzy:
Addad, M.
Djebbari, A.
Powiązania:
https://bibliotekanauki.pl/articles/307793.pdf
Data publikacji:
2018
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
BER
crest factor
multiple access interference
MC-CDMA
peak-to-average power ratio
zero correlation zone
Opis:
In order to meet the demand of high data rate transmission with good quality maintained, the multi-carrier code division multiple access (MC-CDMA) technology is considered for the next generation wireless communication systems. However, their high crest factor (CF) is one of the major drawbacks of multi-carrier transmission systems. Thus, CF reduction is one of the most important research areas in MC-CDMA systems. In addition, asynchronous MC-CDMA suffers from the effect of multiple access interference (MAI), caused by all users active in the system. Degradation of the system’s bit error rate (BER) caused by MAI must be taken into consideration as well. The aim of this paper is to provide a comparative study on the enhancement of performance of an MC-CDMA system. The spreading sequences used in CDMA play an important role in CF and interference reduction. Hence, spreading sequences should be selected to simultaneously ensure low CF and low BER values. Therefore, the effect that correlation properties of sequences exert on CF values is investigated in this study. Furthermore, a numerical BER evaluation, as a function of the signal-to-noise ratio (SNR) and the number of users, is provided. The results obtained indicate that a trade-off between the two criteria is necessary to ensure good performance. It was concluded that zero correlation zone (ZCZ) sequences are the most suitable spreading sequences as far as the satisfaction of the above criteria is concerned.
Źródło:
Journal of Telecommunications and Information Technology; 2018, 3; 9-13
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DAC testing using modulated signals
Autorzy:
Fexa, P.
Verdal, J.
Svatoš, J.
Powiązania:
https://bibliotekanauki.pl/articles/220431.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
digital-to-analog converter
ENOB
Signal-to-noise and distortion - SINAD
FFT analysis
Crest Factor (CF)
Opis:
This document analyses qualities of methods used for testing dynamical parameters of Digital-to-Analog Converters (DAC) using a multi-frequency signal. As the source for these signals, Amplitude Modulated (AM) and Frequency Modulated (FM) signals are used. These signals are often used in radio engineering. Results of the tests, like Effective Number of Bits (ENOB), Signal-to-Noise and Distortion (SINAD), are evaluated in the frequency domain and they are compared with standard results of Sine Wave FFT test methods. The aim of this research is firstly to test whether it is possible to test a DAC using modulated signals, secondly to reduce testing time, while estimating band performance of DAC.
Źródło:
Metrology and Measurement Systems; 2011, 18, 2; 283-293
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bearing estimation using double frequency reassignment for a linear passive array
Autorzy:
Czarnecki, K.
Leśniak, W.
Powiązania:
https://bibliotekanauki.pl/articles/260131.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
direction of arrival
DOA
instantaneous frequency
short-time Fourier transform
STFT
time-frequency reassignment
intercept and surveillance sonar
crest factor
Opis:
The paper demonstrates the use of frequency reassignment for bearing estimation. For this task, signals derived from a linear equispaced passive array are used. The presented method makes use of Fourier transformation based spatial spectrum estimation. It is further developed through the application of two-dimensional reassignment, which leads to obtaining highly concentrated energy distributions in the joint frequency-angle domain and sharp graphical imaging. The introduced method can be used for analysing, a priori, unknown signals of broadband, nonstationary, and/or multicomponent type. For such signals, the direction of arrival is obtained based upon the marginal energy distribution in the angle domain, through searching for arguments of its maxima. In the paper, bearing estimation of three popular types of sonar pulses, including linear and hyperbolic frequency modulated pulses, as well as no frequency modulation at all, is considered. The results of numerical experiments performed in the presence of additive white Gaussian noise are presented and compared to conventional digital sum-delay beamforming performed in the time domain. The root-mean-square error and the peak-to-average power ratio, also known as the crest factor, are introduced in order to estimate, respectively, the accuracy of the methods and the sharpness of the obtained energy distributions in the angle domain.
Źródło:
Polish Maritime Research; 2017, 3; 26-35
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-5 z 5

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