Academic literature on the topic 'Telecommunication systems – Noise'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Telecommunication systems – Noise.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Telecommunication systems – Noise"

1

Kropotov, Y. A., A. A. Belov, and A. Y. Prockuryakov. "Increasing signal/acoustic interference ratio in telecommunications audio exchange by adaptive filtering methods." Information Technology and Nanotechnology, no. 2416 (2019): 271–76. http://dx.doi.org/10.18287/1613-0073-2019-2416-271-276.

Full text
Abstract:
The paper deals with the issues of increasing signal/noise ratio in telecommunication audio exchange systems. The study of characteristics of speech signals and acoustic noises, such as mathematical expectation, dispersion, relative intensity of acoustic speech signals and various types of acoustic noises and interference is carried out. It is shown that in the design of telecommunications systems, in particular loudspeaker systems operating under the influence of external acoustic noise of high intensity, it is necessary to solve the problem of developing algorithms to effectively suppress the above mentioned interference to ensure the necessary signal/noise ratio in communication systems. A mathematical model of the autocorrelation function of the speech signal by using the Lagrange interpolation polynomial of order 10, considered the creation of adaptive algorithms to suppress acoustic noise by linear filtering methods. Thus suppression of acoustic noises and hindrances is possible at the expense of operated change of area of a cutting in the interval from 0 Hz to 300-1000 Hz, depending on a hindrance conditions.
APA, Harvard, Vancouver, ISO, and other styles
2

Кропотов, Юрий, Yuriy Kropotov, Алексей Белов, Aleksey Belov, Александр Проскуряков, and Aleksandr Proskuryakov. "EFFECTIVENESS INCREASE IN AUDIO EXCHANGE TELECOMMUNICATION SYSTEMS UNDER CONDITIONS OF EXTERNAL ACOUSTIC NOISE BY METHODS OF ADAPTIVE FILTERING." Bulletin of Bryansk state technical university 2019, no. 3 (March 27, 2019): 71–77. http://dx.doi.org/10.30987/article_5c8b5cebac6217.27543313.

Full text
Abstract:
Signal processing in the telecommunication systems of audioinformation exchange is conditioned on the requirement in the separation of useful speech acoustic information, in the increase of the verification of information perception by subscribers of a communication system, in the stability increase of telecommunication systems at the suppression of external acoustic interference and echosignal compensations. Therefore during designing telecommunication systems, in particular, speakerphone systems (SS) operating under conditions of an active impact of external acoustic interference and echosignals, there is specified a problem of the algorithm formation of efficient noise suppression for an essential “signal-noise” ratio support. The investigation object is design methods of adaptive algorithms for speech signals processing and acoustic interference suppression at the expense of the controlled change of a rejection area in the range from 0 to 300…1000Hz depending on an interference situation. The work aim is an investigation of the speech signals characteristics and acoustic noise of different nature and also problems consideration in the matter of an algorithm creation for adaptive filtering and suppression of external acoustic interference and echosignals. At that the increase of the “signal-acoustic interference” ratio in the systems of audioexchange telecommunications is carried out through the methods of adaptive filtering. The results obtained in the course of the investigations of different acoustic interference suppression show that through the method of linear filtering in the system of telecommunications of speech information exchange it is possible to ensure the essential ratio Rs/Rak.pom. >20 dB and, accordingly, an essential syllab-ic legibility S ≥ 93%.
APA, Harvard, Vancouver, ISO, and other styles
3

Abbasova, T. S. "Development of rules in expert systems for the analysis and evaluation of telecommunications." Informacionno-technologicheskij vestnik 12, no. 2 (June 30, 2017): 47–63. http://dx.doi.org/10.21499/2409-1650-2017-2-47-63.

Full text
Abstract:
Typical malfunctions that may occur in telecommunication systems due to the failure to meet the noise immunity requirements, as well as the characteristic features that can identify these problems, are analyzed. In the process of developing the knowledge base for the expert system for assessing the telecommunications infrastructure, the existing tools for developing knowledge bases have been improved.
APA, Harvard, Vancouver, ISO, and other styles
4

Lyakhovetsky, L. "Method of estimation of interference noise in transmission systems with orthogonal harmonic signals." Metrology and instruments, no. 3 (March 7, 2018): 17–20. http://dx.doi.org/10.33955/2307-2180(3)2018.17-20.

Full text
Abstract:
The method of estimation of interference noise that arises in transmission systems with orthogonal harmonic signals due to linear distortions of signals in the telecommunication channel is proposed. The method can be used both for simulation of telecommunication systems, and for the construction of measuring devices with the function of estimation of interference noise based on the results of measuring the characteristics of the telecommunication channel.The results of estimation of interference noise for ADSL2 + subscriber access transmission system are presented.
APA, Harvard, Vancouver, ISO, and other styles
5

Kropotov, Yu A., A. A. Belov, A. A. Kolpakov, and A. Yu Proskuryakov. "The syllable intelligibility in the system of information transmission by speech signals depending on the intensity of acoustic noise." Information Technology and Nanotechnology, no. 2416 (2019): 277–82. http://dx.doi.org/10.18287/1613-0073-2019-2416-277-282.

Full text
Abstract:
The paper investigates the effect of the signal-to-noise ratio on syllable intelligibility under the intense influence of external acoustic interference when exchanging voice messages in telecommunication systems of public address systems. The article discusses the effect on the syllable intelligibility of the signal / external acoustic noise ratio, examines the effect of the integral articulation index, the dependence of the perception coefficient of formants on the relative level of formant intensity, the dependence of the formant parameter on the geometric mean frequency of the i-th spectrum of the speech signal. In accordance with the results of studies of the integral articulation index depending on the signal-to-noise ratio, a function of syllable intelligibility depending on the signal-to-noise ratio was obtained, using which it is possible to determine the maximum value of the output signal-to-noise ratio in the audio exchange telecommunications system to obtain a given syllable intelligibility. At the same time, experimentally determined the value of the signal-to-noise ratio in the telecommunications system of audio exchange to obtain a syllable intelligibility of at least 93% for ensure full perception of the transmitted speech information.
APA, Harvard, Vancouver, ISO, and other styles
6

Abbasova, Tatiana Sergeevna, Natalya Petrovna Sidorova, Natalya Nikolaevna Teodorovich, and Elshan Maggeram Oglu Abbasov. "Evaluation of Telecommunications Electromagnetic Compatibility with the Use of Three-Dimensional Modeling Technology." Modern Applied Science 10, no. 10 (July 27, 2016): 224. http://dx.doi.org/10.5539/mas.v10n10p224.

Full text
Abstract:
Three-dimensional modeling is used as a new way of presenting information about the electromagnetic compatibility of telecommunications infrastructure equipment. We analyzed the problem of modeling of electromagnetic noise waves equipment and communication channels of telecommunications monitoring systems. Conducted the analysis of control problems of telecommunications equipment electromagnetic compatibility. Described the real conditions of installing the electronic equipment in computational complexes. Using tools of 3D-modeling was formed cable route, taking into account the suppression of noise waves, placement of telecommunication devices and checking whether the threshold value of cable susceptibility for all options of its gasket between devices was transcended. It is proposed to study the behavior of electromagnetic fields in the cable lines with shielding cable, electrostatic discharge, providing set of measures for electromagnetic compatibility, to convert created in a three-dimensional environment model in a specialized settlement package. The prospects of the use 4D-, 5D-, 6D-simulation for analysis of the implementation of projects, reduction of operating and electromagnetic compatibility costs.
APA, Harvard, Vancouver, ISO, and other styles
7

Kholkina, Natalya. "INFORMATION TRANSFER EFFECTIVENESS OF WARNING AND TELECOMMUNICATION SYSTEMS OF AUDIO-EXCHANGE UNDER NOISE CONDITIONS." Bulletin of Bryansk state technical university 2020, no. 5 (May 13, 2020): 49–55. http://dx.doi.org/10.30987/1999-8775-2020-5-49-55.

Full text
Abstract:
In the paper shown there is presented an approach to the solution of the problem of the effectiveness parameter assessment in telecommunication systems of operational and command communication, systems of warning speakerphone and audio-exchange. There are considered the matters of the dependence investigation of the acoustic speech signal/noise ratio to the assurance of the required syllabic legibility for the possibility to increase the function effectiveness of telecommunication systems and information exchange operated under complex noise situation. There is shown the dependence of formant legibility upon the meaning of average geometric frequencies in each i-th band of a frequency spectrum of acoustic speech signals. The degree of the impact upon syllabic legibility of the acoustic speech signal/noise ratio is shown. In the paper it is shown that for obtaining speech information with syllabic legibility higher than 93% required for complete perception by a subscriber it is necessary to ensure the acoustic signal/noise ratio at the level no less than 20 dB. The problems in the probability density approximation of acoustic signals with the use of generalized polynomials on function basis systems are presented.
APA, Harvard, Vancouver, ISO, and other styles
8

Semenko, Anatoliy, Nikolaj Kushnir, Natalia Bokla, and Yevhen Shestopal. "SYNTHESIS OF STRIP-BAND TELECOMMUNICATION SYSTEM WITH INCREASED CONFIDENTIALITY OF INFORMATION TRANSMISSION THROUGH USE OF PSSEVDOVIDOVYPOVY." Visnyk Universytetu “Ukraina”, no. 1 (28) 2020 (2020): 65–74. http://dx.doi.org/10.36994/2707-4110-2020-1-28-06.

Full text
Abstract:
Currently, special attention is paid to the creation of broadband telecommunications systems with a noise-like signal. Such systems have indisputable advantages in noise immunity, in the confidentiality of information transmission, electromagnetic compatibility with neighboring electronic devices. The formation of a broadband signal in most cases is carried out by the method of direct spreading of the spectrum by manipulating the carrier frequency signal by a pulse pseudo-random sequence (PVP) –m-sequence, Gold, Kasami, Walsh sequence. Sequences such as a well-known attacker can pick up in the receiver and they can not be considered reliable protection of information. The use of the phenomenon of dynamic chaos provides an opportunity to find a new class of PVP, the structure of which is almost impossible to reproduce, so their use provides increased confidentiality of information transmission. PVP generators are built on the basis of one-dimensional chaotic mappings - logistic, quadratic and cubic, which are chaotic systems. When creating a PVP based on chaos, three secret encryption keys are used: for example, for logistic separation, this is the initial value, the equation parameter, and the start of the sequence. To increase the cryptosecurity of telecommunication systems, it is proposed to create PVP based on 2 chaotic signals (by logistic and quadratic mappings), which provides an increase in secret keys from three to six. The paper proposes a scheme for building a telecommunications system with high confidentiality of information transmission through the use of such PVP.
APA, Harvard, Vancouver, ISO, and other styles
9

Pliushch, Oleksandr, Viktor Vyshnivskyi, Volodymyr Tolubko, Vadym Mukhin, Serhii Ishcheryakov, Mykhailo Okhramovych, and Vitalii Loza. "Performance Study of Spread Spectrum Systems with Hard Limiters." International Journal of Computer Network and Information Security 12, no. 5 (October 8, 2020): 1–15. http://dx.doi.org/10.5815/ijcnis.2020.05.01.

Full text
Abstract:
Use of spread spectrum systems in telecommunications is studied. It is shown that spread spectrum techniques can substantially enhance noise and interference immunity in the currently deployed information transmission networks. Primitive polynomials are proposed to obtain respective spreading codes. A spreading code consisting of 1023 chips is synthesized and its characteristics are studied. It is deduced that powerful interferences can exceed dynamic range of the receiving part of the system and, as a result, deteriorate information transmission. To overcome this problem, utilization of limiters is proposed, in which limitation level equals that of the internal noise of the receiving part. Computer simulation is employed to test the performance of the proposed solution. Performance of the spread spectrum system for information transfer is studied both without the limiter and with the limiter. Research results show that, for binary modulation, performance of the system with limitation and without limitation is nearly identical while limiters can substantially reduce requirements for the dynamic range. Compared to the existing approaches, it is proposed to use the synthesized spreading coding sequence with the limitation technique in practical implementations of those telecommunication networks, in which noise immunity and transmission concealment are required, such as in unmanned aerial vehicles. This can replace currently used approaches, such as frequency hopping, transmission power adjustment and antenna pattern changes.
APA, Harvard, Vancouver, ISO, and other styles
10

Matsenko, S., O. Borysenko, S. Spolitis, and V. Bobrovs. "Noise Immunity of the Fibonacci Counter with the Fractal Decoder Device for Telecommunication Systems." Latvian Journal of Physics and Technical Sciences 56, no. 5 (October 1, 2019): 12–21. http://dx.doi.org/10.2478/lpts-2019-0027.

Full text
Abstract:
Abstract The paper presents the improved method of noise immune Fibonacci counting in the minimal form of representation. The method was tested and investigated in the developed noise immune pulse counter based on a minimal form of Fibonacci code with a fractal decoding device. The proposed device, which is simulated in the NI Multisim software, possesses a homogenous structure, increased noise immunity, performance and detection of bit errors in the process of its operation.
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Telecommunication systems – Noise"

1

Tomlin, Toby-Daniel. "Analysis and modelling of jitter and phase noise in electronic systems : phase noise in RF amplifiers and jitter in timing recovery circuits." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0021.

Full text
Abstract:
Timing jitter and phase noise are important design considerations in most electronic systems, particularly communication systems. The desire for faster transmission speeds and higher levels of integration, combined with lower signal levels and denser circuit boards has placed greater emphasis on managing problems related to phase noise, timing jitter, and timing distribution. This thesis reports original work on phase noise modelling in electronic systems. A new model is proposed which predicts the up-conversion of baseband noise to the carrier frequency in RF amplifiers. The new model is validated by comparing the predicted phase noise performance to experimental measurements as it applies to a common emitter (CE), bipolar junction transistor (BJT) amplifier. The results show that the proposed model correctly predicts the measured phase noise, including the shaping of the noise about the carrier frequency, and the dependence of phase noise on the amplifier parameters. In addition, new work relating to timing transfer in digital communication systems is presented. A new clock recovery algorithm is proposed for decoding timing information encoded using the synchronous residual time-stamp (SRTS) method. Again, theoretical analysis is verified by comparison with an experimental implementation. The results show that the new algorithm correctly recovers the source clock at the destination, and satisfies the jitter specification set out by the ITU-T for G.702 signals.
APA, Harvard, Vancouver, ISO, and other styles
2

Ozden, Mehmet T. "Calculated noise performance of a frequency hop sequence system with applications to low altitude satellite communications." Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA242158.

Full text
Abstract:
Thesis (Master of Science in Electrical Engineering)--Naval Postgraduate School, December 1990.
Thesis Advisor: Myers, Glen A. Second Reader: Ha, Tri T. "December 1990." Description based on title screen as viewed on March 30, 2010. DTIC Identifier(s): Antijamming, multipath transmission, frequency hopping, satellite communications, interference, noise, theses. Author(s) subject terms: Frequency hopping, satellite communications. Includes bibliographical references (p. 44). Also available in print.
APA, Harvard, Vancouver, ISO, and other styles
3

Pourbahri, Babak. "Erbium-doped fibre amplifiers and their effects on the phase noise of optical carriers and radio-over-fibre signals." Thesis, University of Kent, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369689.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Jia, Kelin. "Electromagnetic noise generated in the electrified railway propulsion system." Licentiate thesis, KTH, Elektroteknisk teori och konstruktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-31581.

Full text
Abstract:
The electromagnetic compatibility (EMC) problem in the railway propulsion system is a significant safety issue of high concern. The problems can be caused by any part of the propulsion system as well as any combination of the sub systems. Simulation is a fast economical way to understand the system and to predict the EMC performance. In this thesis, the propulsion system is studied partly from the rectifier to the motor. To simulate the rectifier, a two level pulse width modulation (PWM) controlled rectifier is built in Simulink. Time domain line current as well as frequency domain spectra is studied. The spectrum changing according to time variation is obtained. In order to study the high derivative of switching pulse in the insulated gate bipolar transistor (IGBT), a simple circuit is proposed to investigate it. The high frequency noise spectrum is given and the variation of the spectrum due to the reverse recovery time of the ant-parallel diode is also demonstrated. Transmission line theory is used to model the cable used to connect the inverter and motor. The method to extract the characteristic capacitance and inductance matrices of the cable system is presented. Decoupling these characteristic matrices is required for modeling the multiconductor transmission line (MTL) in PSpice. A simple way to decouple them is thus proposed here. Through the simulation studies, we analyze the oscillation and overvoltage in the cable. A fourth cable with optimized layout is also illustrated here to reduce the oscillation on the line. Furthermore, the relationship between the length of line and the noise frequency is studied. Shielding is another way to reduce the electromagnetic (EM) coupling of power lines. The method to model shielded cables in PSpice is given in this thesis. Based on the model we have investigated the shielding effect and analyzed the impact of different grounding conditions on the shielding performance.
QC 20110321
APA, Harvard, Vancouver, ISO, and other styles
5

Pallares, Joan. "Study of industrial environment using Zigbee protocol and modeling industrial noise." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27025.

Full text
Abstract:
This thesis is focused on the industrial environment. This study aims to understand the difficulties wireless communications have when performing in these types of environment with a specific standard (and protocol) Zigbee. These difficulties are due mainly to the physical effects and interferences as well the electromagnetic waves from these wireless transmission signals can suffer. The background of this project is to analyze how industries can implement wireless sensor networks (using Zigbee standard) for their factories in order for them to be beneficial i.e. reliable or if it is possible. Industries normally tend to keep in the path of the old fashioned way i.e. wired systems which are more robust and can cope with the hard system requirements. Some study on these environment effects (interference as well) is performed. The results show how this (Zigbee) sensor network could be or should be implemented in order to have the best performance (disposition of devices, type of environment considering only industrial environments, etc.). Specifically, these results show that Zigbe wireless sensor networks are limited to some conditions in order to obtain the desired reliability. These conditions are that these networks must be performed in absorbing environments, LoS disposition of devices, not too long diatance between devices and not other networks in the same area using the same frequency band. The limitation of absorbing environments is because the dispersion effects in the (highly) reflective environments are critically damageful for the link. The limitation of the other devices operating in the same frequency band in a close area is due to the fact that Zigbee has no frequency diversity. Last but not least, the limitations to LoS and not too long maximum range (approximately 50 meters) are related since the range would be (much) lower than 50 meters if the communication was in NLoS disposition of devices. The noise in this environment is also studied and modeled. The results show that as the impulsive index (which is ameasure of the number of impulses that reach the receiver in a certain unit of time) takes larger values, the distribution approximates that of a Gaussian and as A takes lower values the reults show an impulsive characteristic. The Probability of error is computed for values of A less than 1, where the impulsive characterstic is shown, and as A takes larger values the error is greater.
APA, Harvard, Vancouver, ISO, and other styles
6

Kakkar, Aditya. "Frequency Noise in Coherent Optical Systems: Impact and Mitigation Methods." Doctoral thesis, KTH, Optik och Fotonik, OFO, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207072.

Full text
Abstract:
The increase in capacity demand along with the advancement in digital signal processing (DSP) have recently revived the interest in coherent optical communications and led to its commercialization. However, design and development of robust DSP algorithms for example for carrier phase recovery (CPR) becomes complex as we opt for high order modulation formats such as 16QAM and beyond. Further, electrical-domain dispersion compensation (EDC), while providing many advantages, makes the system more susceptible to laser frequency noise (FN). For instance, in coherent optical links with post-reception EDC, while the transmitter frequency noise causes only phase impairment, the local oscillator (LO) FN in these systems results in a noise enhancement in both amplitude and phase. This noise is commonly known as equalization enhanced phase noise (EEPN). It results in asymmetric requirements for transmitter laser and LO laser. Further, the system design in the presence of lasers with non-white frequency noise becomes increasingly challenging for increased capacity-distance product. The main contributions of this thesis are, firstly, an experimentally validated theory of coherent optical links with lasers having general non-white frequency noise spectrum and corresponding system/laser design criteria and mitigation technique. Secondly, low complexity and high phase noise tolerant CPR for high order modulation formats. The general theory propounded in this thesis elucidates the origin of the laser frequency noise induced noise enhancement in coherent optical links with different DSP configurations. The thesis establishes the existence of multiple frequency noise regimes and shows that each regime results in different set of impairments. The influence of the impairments due to some regimes can ideally be reduced by optimizing the corresponding mitigation algorithms, while other regimes cause irretrievable impairments. Experimentally validated theoretical boundaries of these regimes and corresponding criteria applicable to system/laser design are provided. Further, an EEPN mitigation method and its two possible implementations are proposed and discussed. The thesis also demonstrates an intrinsic limitation of the conventional Blind Phase Search (BPS) algorithm due to angular quantization and provides methods to overcome it. Finally, this thesis proposes and demonstrates single stage and multi-stage carrier phase recovery algorithms for compensation of phase impairments due to the two lasers for higher order circular and square modulations. The proposed methods outperform the state of art algorithms both in performance and in complexity.

QC 20170516


European project ICONE gr. #608099
APA, Harvard, Vancouver, ISO, and other styles
7

Heinrich, Ralph Robert 1954. "Análise das características de propagação em radio enlace de canais banda larga na faixa de UHF." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259662.

Full text
Abstract:
Orientador: Michel Daoud Yacoub
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
Made available in DSpace on 2018-08-23T14:27:26Z (GMT). No. of bitstreams: 1 Heinrich_RalphRobert_M.pdf: 7113070 bytes, checksum: 2a64f903bc44fb31b9ee53ef545bb24e (MD5) Previous issue date: 2013
Resumo: Este projeto de pesquisa objetiva responder a algumas questões sistêmicas levantadas por ocasião do início do desenvolvimento do sistema LTE-450, parte integrante do projeto RASFA - Redes de Acesso Sem Fio Avançadas, conduzido pelo CPqD - Fundação Centro de Pesquisa e Desenvolvimento em Telecomunicações, com recursos do FUNTTEL - Fundo para o Desenvolvimento Tecnológico das Telecomunicações. Esse projeto visa, como um de seus objetivos, o desenvolvimento de um sistema de rádio acesso sem fio LTE-450, operando na faixa de 450 a 470 MHz, baseado na tecnologia LTE - Long Term Evolution. A faixa de 450 a 470 MHz está atribuída em base global desde 2007 para o Serviço Móvel, conforme identificado pela União Internacional de Telecomunicações na World Radiocommunication Conference 2007. A Anatel - Agência Nacional de Telecomunicações - publicou a nova destinação de uso para a faixa de 450 a 470 MHz em 20 de dezembro de 2010, através da Resolução n º 558. Várias ações vêm sendo empreendidas em apoio ao uso da faixa 450 a 470 MHz, para a prestação de serviços banda larga sem fio para áreas rurais, como consta do Programa Nacional de Telecomunicações Rurais, publicado pela Portaria 431/2009 do Ministério das Comunicações, e do Plano Nacional de Banda Larga, publicado em 13 de maio de 2010. Entende-se que a faixa de 450 a 470 MHz é ideal para a implantação de serviços de banda larga sem fio em áreas rurais, devido às suas características de propagação. Por outro lado, a base de conhecimento sobre o canal rádio em sistemas de rádio acesso móvel banda larga considera o uso, em áreas urbanas, de faixas de frequências situadas entre 850 MHz e 3500 MHz. São notórias as diferenças entre as características de propagação nessas faixas e nas faixas de UHF, principalmente quando a área de prestação do serviço deixa de ser a urbana e passa a ser a rural. Nesse sentido, alguns requisitos sistêmicos podem ser questionados e mesmo redimensionados. Esses requisitos foram aqui endereçados através de levantamento de dados em campo e posterior análise crítica contra a base de conhecimento disponível. São questões como a amplitude do desvanecimento seletivo e por despolarização, a intensidade do ruído impulsivo, os modelos de propagação aplicáveis à área rural e à faixa de UHF, a variação da perda de percurso com a altura da antena do terminal e a discriminação de polarização da antena do terminal
Abstract: This research project aims to answer some systemic issues raised during the early development of the LTE-450 radio access system, part of a project RASFA - Advanced Wireless Networks Access, led by CPqD Foundation - Center for Research and Development in Telecommunications with resources of FUNTTEL - Technological Development of Telecommunications Fund. This project aims, as one of its objectives, the development of a LTE-450 wireless system, operating in the 450-470 MHz band, based on LTE - Long Term Evolution technology. The 450-470 MHz band is allocated, on a global basis, since 2007 for Mobile Service, as identified by the International Telecommunication Union in the World Radiocommunication Conference 2007. Anatel - The Brazilian National Telecommunications Agency has published a new destination for the 450-470 MHz band on December 20, 2010, through Resolution No. 558. Several actions have been undertaken in support of the use of the 450-470 MHz band, to provide wireless broadband services to rural areas, as set out in the National Rural Telecommunications Plan, published by the Decree 431/2009 of the Ministry of Communications and the National Broadband Plan (PNBL), published on May 13, 2010. It is understood that the 450-470 MHz band is ideal for deploying wireless broadband services in rural areas, due to its propagation characteristics. On the other hand, the base of knowledge about the mobile broadband access radio systems channel, considering the use in urban areas, situated between 850 MHz and 3500 MHz bands have notable differences between the propagation characteristics of these bands and the UHF bands, especially when the area of service provision ceases to be the urban and goes to the rural areas. Thus, some systemic requirements can be questioned and even resized. These requirements are addressed here through field data gathering and subsequent critical analysis against the knowledge base available. These issues are such as the extent of selective fading and depolarization, the intensity of the impulse noise, the propagation models applicable to the rural area and the UHF band, the variation of the path loss with the height of the terminal antenna and of terminal antenna polarization discrimination
Mestrado
Telecomunicações e Telemática
Mestre em Engenharia Elétrica
APA, Harvard, Vancouver, ISO, and other styles
8

Familua, Ayokunle Damilola. "Classification and modeling of power line noise using machine learning techniques." Thesis, 2017. https://hdl.handle.net/10539/24183.

Full text
Abstract:
A thesis submitted in ful lment of the requirements for the degree of Doctor of Philosophy in the School of Electrical and Information Engineering Faculty of Engineering and Built Environment June 2017
The realization of robust, reliable and e cient data transmission have been the theme of recent research, most importantly in real channel such as the noisy, fading prone power line communication (PLC) channel. The focus is to exploit old techniques or create new techniques capable of improving the transmission reliability and also increasing the transmission capacity of the real communication channels. Multi-carrier modulation scheme such as Orthogonal Frequency Division Multiplexing (OFDM) utilizing conventional single-carrier modulation is developed to facilitate a robust data transmission, increasing transmission capacity (e cient bandwidth usage) and further reducing design complexity in PLC systems. On the contrary, the reliability of data transmission is subjected to several inhibiting factors as a result of the varying nature of the PLC channel. These inhibiting factors include noise, perturbation and disturbances. Contrary to the Additive White Gaussian noise (AWGN) model often assumed in several communication systems, this noise model fails to capture the attributes of noise encountered on the PLC channel. This is because periodic noise or random noise pulses injected by power electronic appliances on the network is a deviation from the AWGN. The nature of the noise is categorized as non-white non-Gaussian and unstable due to its impulsive attributes, thus, it is labeled as Non-additive White Gaussian Noise (NAWGN). These noise and disturbances results into long burst errors that corrupts signals being transmitted, thus, the PLC is labeled as a horrible or burst error channel. The e cient and optimal performance of a conventional linear receiver in the white Gaussian noise environment can therefore be made to drastically degrade in this NAWGN environment. Therefore, transmission reliability in such environment can be greatly enhanced if we know and exploit the knowledge of the channel's statistical attributes, thus, the need for developing statistical channel model based on empirical data. In this thesis, attention is focused on developing a recon gurable software de ned un-coded single-carrier and multicarrier PLC transceiver as a tool for realizing an optimized channel model for the narrowband PLC (NB-PLC) channel. First, a novel recon gurable software de ned un-coded single-carrier and multi-carrier PLC transceiver is developed for real-time NB-PLC transmission. The transceivers can be adapted to implement di erent waveforms for several real-time scenarios and performance evaluation. Due to the varying noise parameters obtained from country to country as a result of the dependence of noise impairment on mains voltages, topology of power line, place and time, the developed transceivers is capable of facilitating constant measurement campaigns to capture these varying noise parameters before statistical and mathematically inclined channel models are derived. Furthermore, the single-carrier (Binary Phase Shift Keying (BPSK), Di erential BPSK (DBPSK), Quadrature Phase Shift Keying (QPSK) and Di erential QPSK (DQPSK)) PLC transceiver system developed is used to facilitate a First-Order semi-hidden Fritchman Markov modeling (SHFMM) of the NB-PLC channel utilizing the e cient iterative Baum- Welch algorithm (BWA) for parameter estimation. The performance of each modulation scheme is evaluated in a mildly and heavily disturbed scenarios for both residential and laboratory site considered. The First-Order estimated error statistics of the realized First- Order SHFMM have been analytically validated in terms of performance metrics such as: log-likelihood ratio (LLR), error-free run distribution (EFRD), error probabilities, mean square error (MSE) and Chi-square ( 2) test. The reliability of the model results is also con rmed by an excellent match between the empirically obtained error sequence and the SHFMM regenerated error sequence as shown by the error-free run distribution plot. This thesis also reports a novel development of a low cost, low complexity Frequency-shift keying (FSK) - On-o keying (OOK) in-house hybrid PLC and VLC system. The functionality of this hybrid PLC-VLC transceiver system was ascertained at both residential and laboratory site at three di erent times of the day: morning, afternoon and evening. A First and Second-Order SHFMM of the hybrid system is realized. The error statistics of the realized First and Second-Order SHFMMs have been analytically validated in terms of LLR, EFRD, error probabilities, MSE and Chi-square ( 2). The Second-Order SHFMMs have also been analytically validated to be superior to the First-Order SHFMMs although at the expense of added computational complexity. The reliability of both First and Second-Order SHFMM results is con rmed by an excellent match between the empirical error sequences and SHFMM re-generated error sequences as shown by the EFRD plot. In addition, the multi-carrier (QPSK-OFDM, Di erential QPSK (DQPSK)-OFDM) and Di erential 8-PSK (D8PSK)-OFDM) PLC transceiver system developed is used to facilitate a First and Second-Order modeling of the NB-PLC system using the SHFMM and BWA for parameter estimation. The performance of each OFDM modulation scheme in evaluated and compared taking into consideration the mildly and heavily disturbed noise scenarios for the two measurement sites considered. The estimated error statistics of the realized SHFMMs have been analytically validated in terms of LLR, EFRD, error probabilities, MSE and Chi-square ( 2) test. The estimated Second-Order SHFMMs have been analytically validated to be outperform the First-Order SHFMMs although with added computational complexity. The reliability of the models is con rmed by an excellent match between the empirical data and SHFMM generated data as shown by the EFRD plot. The statistical models obtained using Baum-Welch to adjust the parameters of the adopted SHFMM are often locally maximized. To solve this problem, a novel Metropolis-Hastings algorithm, a Bayesian inference approach based on Markov Chain Monte Carlo (MCMC) is developed to optimize the parameters of the adopted SHFMM. The algorithm is used to optimize the model results obtained from the single-carrier and multi-carrier PLC systems as well as that of the hybrid PLC-VLC system. Consequently, as deduced from the results, the models obtained utilizing the novel Metropolis-Hastings algorithm are more precise, near optimal model with parameter sets that are closer to the global maxima. Generally, the model results obtained in this thesis are relevant in enhancing transmission reliability on the PLC channel through the use of the models to improve the adopted modulation schemes, create adaptive modulation techniques, develop and evaluate forward error correction (FEC) codes such as a concatenation of Reed-Solomon and Permutation codes and other robust codes suitable for exploiting and mitigating noise impairments encountered on the low voltage NB-PLC channel. Furthermore, the recon gurable software de ned NB-PLC transceiver test-bed developed can be utilized for future measurement campaign as well as adapted for multiple-input and multiple-output (MIMO) PLC applications.
MT2018
APA, Harvard, Vancouver, ISO, and other styles
9

"Error control coded data transmision over FM supplementary signal transmission radio channels." Thesis, 2015. http://hdl.handle.net/10210/14748.

Full text
Abstract:
M.Ing. (Electrical and Electronic Engineering)
With all the talk about the Information Highway and its construction, there is also a channel which is highly underestimated and thus almost ignored. On normal FM radio transmissions extra bandwidth exists, suitable for the transmission of audio and data. In this thesis the effects of interference on data transmission over the Supplementary Signal Transmission (SST) channel are analysed. The channel is characterized in terms of the Bit Error Rate (BER) versus field strength and distance from a transmitter ...
APA, Harvard, Vancouver, ISO, and other styles
10

Rodrigo, Navarro Jaime. "Phase Noise Tolerant Modulation Formats and DSP Algorithms for Coherent Optical Systems." Doctoral thesis, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207034.

Full text
Abstract:
Coherent detection together with multilevel modulation formats has the potential to significantly increase the capacity of existing optical communication systems at no extra cost in signal bandwidth. However, these modulation formats are more susceptible to the impact of different noise sources and distortions as the distance between its constellation points in the complex plane reduces with the modulation index. In this context, digital signal processing (DSP) plays a key role as it allows compensating for the impairments occurring during signal generation, transmission and/or detection relaxing the complexity of the overall system. The transition towards pluggable optical transceivers, offers flexibility for network design/upgrade but sets strict requirements on the power consumption of the DSP thus limiting its complexity. The DSP module complexity however, scales with the modulation order and, in this scenario, low complex yet high performance DSP algorithms are highly desired. In this thesis, we mainly focus on the impact of laser phase noise arising from the transmitter and local oscillator (LO) lasers in coherent optical communication systems employing high order modulation formats. In these systems, the phase noise of the transmitting and LO lasers translate into phase noise in the received constellation impeding the proper recovery of the transmitted data. In order to increase the system phase noise tolerance, we firstly explore the possibility of re-arranging the constellation points in a circularly shaped mQAM (C-mQAM) constellation shape to exploit its inherent phase noise tolerance. Different low-complex carrier phase recovery (CPR) schemes applicable to these constellations are proposed along with a discussion on its performance and implementation complexity. Secondly, the design guidelines of high performance and low complex CPR schemes for conventional square mQAM constellations are presented. We identify the inherent limitation of the state-of-the-art blind phase search (BPS) carrier phase recovery algorithm which hinders its achievable performance and implementation complexity and present a low complex solution to overcome it. The design guidelines of multi-stage CPR schemes for high order modulation formats, where the BPS algorithm is employed at any of the stages, are also provided and discussed. Finally, the interplay between the received dispersed signal and the LO phase noise is analytically investigated to characterize the origin of the equalization enhanced phase noise phenomena.

QC 20170516


EU project ICONE, gr. #608099
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Telecommunication systems – Noise"

1

Ziemer, Rodger E. Principles of communications: Systems, modulation, and noise. 4th ed. New York: Wiley, 1995.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

H, Tranter William, ed. Principles of communications: Systems, modulation, and noise. 4th ed. Boston: Houghton Mifflin Co., 1995.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

H, Tranter William, ed. Principles of communications: Systems, modulation, and noise. 5th ed. New York: Wiley, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Ziemer, Rodger E. Principles of communications: Systems, modulation, and noise. 3rd ed. Boston: Houghton Mifflin Co., 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

H, Tranter William, ed. Principles of communications: Systems, modulation, and noise. 6th ed. Hoboken, NJ: Wiley, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

H, Tranter William, ed. Principles of communications: Systems, modulation, and noise. 2nd ed. Boston: Houghton Mifflin, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Carlson, A. Bruce. Communication systems: An introduction to signals and noise in electrical communication. 4th ed. Boston: McGraw-Hill, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Carlson, A. Bruce. Communication systems: An introduction to signals and noise in electrical communication. 5th ed. Dubuque, IA: McGraw-Hill, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Carlson, A. Bruce. Communication systems: An introduction to signals and noise in electrical communication. 3rd ed. New York: McGraw-Hill, 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Carlson, A. Bruce. Communication systems: An introduction to signals and noise in electrical communication. 4th ed. Boston: McGraw-Hill, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Telecommunication systems – Noise"

1

Dunlop, J., and D. G. Smith. "Noise in analogue communications systems." In Telecommunications Engineering, 122–44. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4899-2929-7_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Dunlop, J., and D. G. Smith. "Noise in digital communications systems." In Telecommunications Engineering, 145–72. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4899-2929-7_5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Dunlop, J., and D. G. Smith. "Noise in Analogue Communications Systems." In Telecommunications Engineering, 124–47. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4615-8004-1_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Dunlop, J., and D. G. Smith. "Noise in Digital Communications Systems." In Telecommunications Engineering, 148–74. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4615-8004-1_5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Panaro, J. S. G., and C. de Almeida. "Performance Analysis of Multidimensional PPM Codes for Optical CDMA Systems in the Presence of Noise." In Telecommunications and Networking - ICT 2004, 312–21. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-540-27824-5_43.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Udrea, Radu Mihnea, Claudia Cristina Oprea, and Cristian Stanciu. "Multi-microphone Noise Reduction System Integrating Nonlinear Multi-band Spectral Subtraction." In Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 133–38. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-74935-8_19.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Garnaev, Andrey, Wade Trappe, and Athina Petropulu. "Maxmin Strategy for a Dual Radar and Communication OFDM Waveforms System Facing Uncertainty About the Background Noise." In Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 154–64. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-05490-8_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

N., Manjunatha K., Raghu N., and Kiran B. "Evalutation of Turbo Decoder Performance Through Software Reference Model." In Advances in Wireless Technologies and Telecommunication, 179–97. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-6988-7.ch011.

Full text
Abstract:
Turbo encoder and decoder are two important blocks of long-term evolution (LTE) systems, as they address the data encoding and decoding in a communication system. In recent years, the wireless communication has advanced to suit the user needs. The power optimization can be achieved by proposing early termination of decoding iteration where the number of iterations is made adjustable which stops the decoding as it finishes the process. Clock gating technique is used at the RTL level to avoid the unnecessary clock given to sequential circuits; here clock supplies are a major source of power dissipation. The performance of a system is affected due to the numbers of parameters, including channel noise, type of decoding and encoding techniques, type of interleaver, number of iterations, and frame length on the Matlab Simulink platform. A software reference model for turbo encoder and decoder are modeled using MATLAB Simulink. Performance of the proposed model is estimated and analyzed on various parameters like frame length, number of iterations, and channel noise.
APA, Harvard, Vancouver, ISO, and other styles
9

Danish, Emad Abdullah, and Mazin I. Alshamrani. "QoE-Driven Efficient Resource Utilisation for Video Over Critical Communication Systems." In Advances in Wireless Technologies and Telecommunication, 168–87. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-2113-6.ch008.

Full text
Abstract:
Research in network resource utilisation introduced several techniques for more efficient power and bandwidth consumption. The majority of these techniques, however, were based on Quality of Service (QoS) and network parameters. Therefore, in this study a different approach is taken to investigate the possibility of a more efficient resource utilisation if resources are distributed based on users' Quality of Experience (QoE), in the context of 3D video transmission over WiMAX access networks. In particular, this study suggests a QoE-driven technique to identify the operational regions (bounds) for Modulation and Coding Schemes (MCS). A mobile 3D video transmission is simulated, through which the correlation between receiver's Signal-to-Noise Ratio (SNR) and perceived video quality is identified. The main conclusions drawn from the study demonstrate that a considerable saving in signal power and bandwidth can be achieved in comparison to QoS-based techniques.
APA, Harvard, Vancouver, ISO, and other styles
10

Swami, Deb Sunder, and Kandarpa Kumar Sarma. "A logistic-Map-Based PN Sequence for Stochastic Wireless Channels." In Advances in Wireless Technologies and Telecommunication, 155–81. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-2342-0.ch008.

Full text
Abstract:
The work in this chapter mainly focusses on a pseudo-noise (PN) sequence generator which is constructed exploiting the features of one-dimensional chaotic systems such as a logistic map. The use of logistic map to generate strong cryptographic sequences is novel in approach in terms of its use with a range of transmission techniques for wireless communication because it is easy to conceive and requires simple devices to generate the sequence. The generated sequence is used as a spreading sequence in a DS-SS modulation multipath environment with AWGN and Rayleigh fading channel, under various channel fading conditions. The BER curves and channel impulse responses are obtained and compared with the existing linear feedback shift register (LFSR) based PN sequence and Kasami sequence. Results from this comparative analysis indicate that the proposed method generally yields a greater number of reliable, unpredictable and random bits than existing techniques under the same conditions and can be practically implemented for DS-SS scheme as a spreading sequence.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Telecommunication systems – Noise"

1

Maddox, P. R. "An integrated solution for ambient noise reduction in telecommunication applications." In IEE Colloquium on Adaptive Signal Processing for Mobile Communication Systems. IEE, 1997. http://dx.doi.org/10.1049/ic:19971312.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Kropotov, Yuriy A., Aleksey A. Belov, and Aleksander Y. Proskuryakov. "Signal Models in Telecommunication Systems of Audio Exchange in Conditions of Acoustic Noise." In 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE). IEEE, 2018. http://dx.doi.org/10.1109/apeie.2018.8545882.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Kholkina, Natalia Evgenievna, Aleksander Yurievich Proskuryakov, and Aleksey Anatolievich Belov. "Development of an Algorithm for Suppression of Concentrated Acoustic Noise in Telecommunication Systems." In 2021 23rd International Conference on Digital Signal Processing and its Applications (DSPA). IEEE, 2021. http://dx.doi.org/10.1109/dspa51283.2021.9535906.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

IIchenko, M. E., O. N. Lebedev, and I. L. Polyakov. "Estimation of a noise stability address code sets for CDMA-systems." In 2005 15th International Crimean Conference Microwave and Telecommunication Technology. IEEE, 2005. http://dx.doi.org/10.1109/crmico.2005.1564910.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Grichkin, S. E., and E. P. Stroganova. "Phase Noise Measurement for Stabilized Oscillators." In 2018 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF). IEEE, 2018. http://dx.doi.org/10.1109/weconf.2018.8604357.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Alimuradov, Alan, Alexander Tychkov, Pyotr Churakov, Yury Kvitka, Alexey Zaretskiy, and Galina Vishnevskaya. "Noise-Robust Algorithm for "Speech/Pause" Segmentation in Diagnostic Systems of Psychogenic States." In 2016 International Conference on Engineering and Telecommunication (EnT). IEEE, 2016. http://dx.doi.org/10.1109/ent.2016.009.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Deng, Hao, Hui-Ming Wang, Yi Zhang, Qian Yang, Xueqin Jiang, and Wenjie Wang. "The impact of relative distance on artificial-noise-aided secure transmission." In 2016 International Conference on Computer, Information and Telecommunication Systems (CITS). IEEE, 2016. http://dx.doi.org/10.1109/cits.2016.7546418.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Yachnaya, V. O., M. A. Mikhalkova, E. N. Yablokov, and V. R. Lutsiv. "Noise Model Effect upon the GAN-Synthesized Images." In 2020 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF). IEEE, 2020. http://dx.doi.org/10.1109/weconf48837.2020.9131529.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Shelkovnikov, B. N., V. S. Mahonya, A. N. Peshkov, V. L. Lomaka, D. Budimir, and A. Shelkovnikov. "Simulation tools and examples of devices and telecommunication systems under influence of modulated signals and noise." In 2003 13th International Crimean Conference 'Microwave and Telecommunication Technology' Conference Proceedings. IEEE, 2003. http://dx.doi.org/10.1109/crmico.2003.158843.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Zongru Liu, E. Skafidas, and R. J. Evans. "Phase noise reduction techniques for multigigabit per second OFDM systems operating at 60 GHz." In 2007 Australasian Telecommunication Networks and Applications Conference (ATNAC 2007). IEEE, 2007. http://dx.doi.org/10.1109/atnac.2007.4665263.

Full text
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography