Relevant bibliographies by topics / Detection of symbol length

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Detection of symbol length'

Author: Grafiati
Published: 4 June 2021
Last updated: 2 February 2022

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 'Detection of symbol length.'

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 "Detection of symbol length"

1

Wu, Yan Jun, Gang Fu, and Gang Cheng. "Pulse Coding Soft FM Telemetry Signal Demodulation." Advanced Materials Research 989-994 (July 2014): 3952–55. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.3952.

Full text
Abstract:
The traditional method of demodulation for PCM/FM telemetry demodulation threshold is higher and the computation of the larger problem, research an orthogonal baseband after rotation, Symbol Detection (Multi - Symbol Detection, MSD) technology: the first frequency under the intermediate frequency digital telemetry signals processing, single sign on orthogonal baseband signal correlation matching, and then apply compound spinning technology to meet at the same time for multiple element symbols at the same time Detection, the purpose of the final design step length synchronization method with demodulation smoothly.
APA, Harvard, Vancouver, ISO, and other styles
2

Fu, Gang, Yue Feng, and Wen Jian Geng. "Study of Symbol Detection Performance of Two Kinds of Compensation Method." Applied Mechanics and Materials 602-605 (August 2014): 2294–97. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.2294.

Full text
Abstract:
Pulse coding/frequency modulation (PCM/FM) system is a rocket system mainly adopts remote sensing system, and MSD (Multi - Symbol Detection) is to overcome the traditional demodulation methods threshold effect. For multiple symbol detection misjudgment rate is higher in the process of problem, put forward two compensation methods: under the premise of without changing the length of the observation, every time by changing the length of sliding between the ruling and ultimately achieve the purpose of reduce misjudgment. The simulation analysis and test results verified the effectiveness and applicability of two kinds of compensation algorithm.
APA, Harvard, Vancouver, ISO, and other styles
3

Ganapathy, Nagarajan, Diana Baumgärtel, and Thomas Deserno. "Automatic Detection of Atrial Fibrillation in ECG Using Co-Occurrence Patterns of Dynamic Symbol Assignment and Machine Learning." Sensors 21, no. 10 (May 19, 2021): 3542. http://dx.doi.org/10.3390/s21103542.

Full text
Abstract:
Early detection of atrial fibrillation from electrocardiography (ECG) plays a vital role in the timely prevention and diagnosis of cardiovascular diseases. Various algorithms have been proposed; however, they are lacking in considering varied-length signals, morphological transitions, and abnormalities over long-term recordings. We propose dynamic symbolic assignment (DSA) to differentiate a normal sinus rhythm (SR) from paroxysmal atrial fibrillation (PAF). We use ECG signals and their interbeat (RR) intervals from two public databases namely, AF Prediction Challenge Database (AFPDB) and AF Termination Challenge Database (AFTDB). We transform RR intervals into a symbolic representation and compute co-occurrence matrices. The DSA feature is extracted using varied symbol-length V, word-size W, and applied to five machine learning algorithms for classification. We test five hypotheses: (i) DSA captures the dynamics of the series, (ii) DSA is a reliable technique for various databases, (iii) optimal parameters improve DSA’s performance, (iv) DSA is consistent for variable signal lengths, and (v) DSA supports cross-data analysis. Our method captures the transition patterns of the RR intervals. The DSA feature exhibit a statistically significant difference in SR and PAF conditions (p < 0.005). The DSA feature with W=3 and V=3 yield maximum performance. In terms of F-measure (F), rotation forest and ensemble learning classifier are the most accurate for AFPDB (F = 94.6%) and AFTDB (F = 99.8%). Our method is effective for short-length signals and supports cross-data analysis. The DSA is capable of capturing the dynamics of varied-lengths ECG signals. Particularly, the optimal parameters-based DSA feature and ensemble learning could help to detect PAF in long-term ECG signals. Our method maps time series into a symbolic representation and identifies abnormalities in noisy, varied-length, and pathological ECG signals.
APA, Harvard, Vancouver, ISO, and other styles
4

Zhang, Gaoyuan, Haiqiong Li, Congzheng Han, Congyu Shi, Hong Wen, and Dan Wang. "Multiple-Symbol Detection Scheme for IEEE 802.15.4c MPSK Receivers over Slow Rayleigh Fading Channels." Security and Communication Networks 2021 (May 20, 2021): 1–19. http://dx.doi.org/10.1155/2021/6641192.

Full text
Abstract:
Although the full multiple-symbol detection (MSD) for IEEE 802.15.4c multiple phase shift keying (MPSK) receivers gives much better performance than the symbol-by-symbol detection (SBSD), its implementation complexity is extremely heavy. We propose a simple MSD scheme based on two implementation-friendly but powerful strategies. First, we find the best and second-best decisions in each symbol position with the standard SBSD procedure, and the global best decision is frozen. Second, for the remaining symbol positions, only the best and second-best symbol decisions, not all the candidates, are jointly searched by the standard MSD procedure. The simulation results indicate that the packet error rate (PER) performance of the simplified MSD scheme is almost the same as that of the full scheme. In particular, at PER of 1 × 10 − 3 , no more than 0.2 dB performance gap is observed if we just increase the observation window length N to 2. However, the number of decision metrics needed to be calculated is reduced from 256 to 2. Thus, much balance gain between implementation complexity and detection performance is achieved.
APA, Harvard, Vancouver, ISO, and other styles
5

Shi, Congyu, Gaoyuan Zhang, Haiqiong Li, Congzheng Han, Jie Tang, Hong Wen, Longye Wang, and Dan Wang. "Reduced-Complexity Multiple-Symbol Detection of O-QPSK Signals in Smart Metering Utility Networks." Electronics 9, no. 12 (December 2, 2020): 2049. http://dx.doi.org/10.3390/electronics9122049.

Full text
Abstract:
In this work, an implementation-friendly multiple-symbol detection (MSD) scheme is proposed for the IEEE 802.15.4g offset quadrature phase shift keying (O-QPSK) receivers over the slow fading channel. The full MSD scheme presents better detection performance than the symbol-by-symbol detection (SBSD) scheme, yet its complexity increases exponentially as the observation window length increases. We introduce a simplified MSD scheme based on two powerful strategies. We first seek the optimal and suboptimal decisions in each symbol position with the standard SBSD procedure. Then, the aforementioned optimal and suboptimal decisions instead of all candidates are jointly searched with the standard MSD procedure. That is, only the most and second most reliable candidates in each symbol position are selected to participate in the final detection. The simulation results demonstrate that the new MSD scheme can achieve more encouraging energy gain than the SBSD scheme, while the high complexity of full MSD is also effectively reduced. A more legitimate compromise between detection performance and complexity is thus accomplished, which enables smart metering utility networks (SUN) nodes to achieve energy saving and maximum service life.
APA, Harvard, Vancouver, ISO, and other styles
6

Zhu, Dong Xu, Gang Fu, and Qian He. "A Kind of MSD Performance Compensation Method Based on the Strategy of Sliding." Advanced Materials Research 989-994 (July 2014): 2360–63. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.2360.

Full text
Abstract:
The signal noise ratio (SNR) of telemetry signals is low in the environment of reentry telemetry, MSD(Multi-Symbol Detection) technology can effectively improve PCM/FM telemetry signal demodulation performance. In view of the problem that maximum likelihood value is misjudged leaded by the noise in the process of reentry and doppler causing serious distortion of signal phase. A performance compensation method of MSD based on sliding strategy is researched: A MSD operation with N-1 element overlap before each MSD operation, where the each symbol sliding strategy sliding the length of 1 symbol. The simulation and test results verify the effectiveness of the improved algorithm.
APA, Harvard, Vancouver, ISO, and other styles
7

Fu, Gang, Dong Xu Zhu, Ren Long Li, and Li Ping Wang. "Research on Soft Demodulation of Anamorphic PCM/FM Signal under the Condition of Low SNR." Applied Mechanics and Materials 532 (February 2014): 147–51. http://dx.doi.org/10.4028/www.scientific.net/amm.532.147.

Full text
Abstract:
Reentry telemetry channel is a special channel in the process of remote sensing, black barrier and multipath effect will cause the PCM/FM telemetry signal-to-noise ratio and frequency selective fading , even break through the traditional demodulation method of demodulation threshold, led to the bit error rate is greatly increased when aircraft fly through the reentry telemetry channel. Aiming at the problem, a sliding length of 1 more Symbol Detection (Multi - Symbol Detection, MSD) demodulation algorithm is studied: the continuous observations of N element signal and local signal for joint Detection, but each time the MSD sentences a MSD earlier with N - 1 element coincidence. In theory, the algorithm can increase the channel gain about 3 db, the simulation and test results verified the effectiveness of the proposed algorithm.
APA, Harvard, Vancouver, ISO, and other styles
8

YU, Yang, Shiro HANDA, Fumihito SASAMORI, and Osamu TAKYU. "Adaptive Iterative Decoding of Finite-Length Differentially Encoded LDPC Coded Systems with Multiple-Symbol Differential Detection." IEICE Transactions on Communications E96.B, no. 3 (2013): 847–58. http://dx.doi.org/10.1587/transcom.e96.b.847.

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

Zhang, Gaoyuan, Congzheng Han, Baofeng Ji, Congyu Shi, Ping Xie, and Ling Yang. "A New Multiple-Symbol Differential Detection Strategy for Error-Floor Elimination of IEEE 802.15.4 BPSK Receivers Impaired by Carrier Frequency Offset." Wireless Communications and Mobile Computing 2019 (November 26, 2019): 1–26. http://dx.doi.org/10.1155/2019/5409612.

Full text
Abstract:
In this paper, we pay our attention towards the noncoherent demodulation aspect of binary phase shift keying (BPSK) receivers for IEEE 802.15.4 wireless sensor networks (WSNs), and a carrier frequency offset invariant as well as error-floor free multiple-symbol differential detection (MSDD) strategy is proposed over the flat fading channel. This detector is an alternative to the multiple-symbol detector that has been considered almost exclusively in the past. In this new configuration, the receivers do not perform chip-level precompensation as in conventional scheme but bit-level postcompensation. That is, the bit-level autocorrelation operation is first implemented with the “raw” chip sample, and then the carrier frequency offset effect (CFOE) embedded in the achieved statistic is compensated. Correspondingly, the cumulative error in the detection metric is decreased so much that the pervasive error floor for the conventional MSDD scheme is suppressed. Also, complexity efficient estimators for the MSDD scheme are reinvestigated, analyzed, and summarized. Simulation results demonstrate that this new detection strategy may achieve rather more encouraging gain from differential and spread spectrum coding than the conventional single differential coherent detection (SDCD) scheme. The pervasive error floor is also eliminated as compared with conventional MSDD scheme even if the most simple estimator is configured under large bit observation length. Then, much transmitting energy may be saved for each chip symbol, which is practically desired for transmit-only nodes in WSNs.
APA, Harvard, Vancouver, ISO, and other styles
10

Song, Lijun, Xia Lei, Maozhu Jin, and Zhihan Lv. "Joint Channel Estimation and Signal Detection for the OFDM System Without Cyclic Prefix Over Doubly-Selective Channels." International Journal of Bifurcation and Chaos 25, no. 14 (December 30, 2015): 1540028. http://dx.doi.org/10.1142/s0218127415400283.

Full text
Abstract:
In the high-speed railway wireless communication, a joint channel estimation and signal detection algorithm is proposed for the orthogonal frequency division multiplexing (OFDM) system without cyclic prefix in the doubly-selective fading channels. Our proposed method first combines the basis expansion model (BEM) and the inter symbol interference (ISI) cancellation to overcome the situation that exists with the fast time-varying channel and the normalized maximum multipath channel exceeding the length of the cyclic prefix (CP). At first, the channel estimation and signal detection can be approximated without considering the ISI. Then, the channel parameters and signal detection are updated through ISI cancellation and circular convolution reconstruction from the frequency domain. The simulations show the algorithm can improve the performance of channel estimation and signal detection.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Detection of symbol length"

1

Kubánková, Anna. "Automatická klasifikace digitálních modulací." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-233424.

Full text
Abstract:
This dissertation thesis deals with a new method for digital modulation recognition. The history and present state of the topic is summarized in the introduction. Present methods together with their characteristic properties are described. The recognition by means of artificial neural is presented in more detail. After setting the objective of the dissertation thesis, the digital modulations that were chosen for recognition are described theoretically. The modulations FSK, MSK, BPSK, QPSK, and QAM-16 are concerned. These modulations are mostly used in modern communication systems. The method designed is based on the analysis of module and phase spectrograms of the modulated signals. Their histograms are used for the examination of the spectrogram properties. They provide information on the count of carrier frequencies in the signal, which is used for the FSK and MSK recognition, and on the count of phase states on which the BPSK, QPSK, and QAM-16 are classified. The spectrograms in that the characteristic attributes of the modulations are visible are obtained with the segment length equal to the symbol length. It was found that it is possible to correctly recognize the modulation with the known symbol length at the signal-to-noise ratio at least 0 dB. That is why it is necessary to detect the symbol length prior to the spectrogram calculation. Four methods were designed for this purpose: autocorrelation function, cepstrum analysis, wavelet transform, and LPC coefficients. These methods were algorithmized and analyzed with signals disturbed by the white Gaussian noise, phase noise and with signals passed through a multipass fading channel. The method of detection by means of cepstrum analysis proved the most suitable and reliable. Finally the new method for digital modulation recognition was verified with signals passed through a channel with properties close to the real one.
APA, Harvard, Vancouver, ISO, and other styles
2

Park, Sang Woo. "Efficient blind symbol rate estimation and data symbol detection algorithms for linearly modulated signals." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2729.

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

Cheng, ChienChun. "MIMO signal design, channel estimation, and symbol detection." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLC003/document.

Full text
Abstract:
Cette thèse aborde plusieurs problèmes fondamentaux des systèmes de communications sans fil avec des antennes multiples, dites systèmes MIMO (multiple input, multiple output). Les contributions se situent aussi bien au niveau des algorithmes de réception qu’au niveau de la génération du signal à l’émission.La plus grande partie de la thèse est dédiée à l’étude des algorithmes de réception. Les points abordés comprennent la modélisation et l’estimation du canal, la détection robuste des symboles, et la suppression des interférences. Un nouveau modèle de canal est proposé dans le chapitre 3 en exploitant les corrélations dans les domaines temporel, fréquentiel et spatial, et en réduisant l’espace des paramètres aux termes dominants. Ce modèle est utilisé pour proposer ensuite un estimateur de canal à faible complexité et aussi un sélecteur de mots de code pour envoyer vers l’émetteur les informations sur l’état du canal. Dans le chapitre 4, la réception robuste est étudiée pour les systèmes MIMO-OFDM sans une connaissance parfaite du canal. Des récepteurs robustes sont proposés pour les cas avec ou sans connaissance statistique du canal. La conception de récepteurs pour les systèmes MIMO-OFDM en présence d’interférence est étudiée dans le chapitre 5 et des récepteurs robustes sont proposés prenant en compte séparément l’interférence causée par les ondes pilotes et celle causée par les symboles d’une part et l’asynchronisme entre le signal et l’interférence d’autre part.Dans la deuxième partie de la thèse (chapitre 6), nous abordons les modulations spatiales qui sont particulièrement adaptées aux systèmes MIMO dans lesquels le nombre de chaines d’émission est inférieur aux nombre d’antennes. Remarquant que l’efficacité spectrale de ces systèmes reste très faible par rapport à la technique de multiplexage spatiale, nous avons développé des modulations spatiales améliorées (ESM, pour Enhanced Spatial Modulation) qui augmentent substantiellement l’efficacité spectrale. Ces modulations sont basées sur l’introduction de modulations secondaires, obtenues par interpolation. La technique ESM gagne plusieurs décibels en rapport signal à bruit lorsque les constellations du signal sont choisies de façon à avoir la même efficacité spectrale que dans les modulations spatiales conventionnelles
The aim of this thesis is to investigate multiple input multiple output (MIMO) techniques from the reception algorithms, i.e., channel estimation, symbol detection, and interference suppression, to the advanced spatial modulation (SM) transmission schemes, i.e., the signal constellation design for high performance and energy efficiency. In the reception algorithms, the proposed schemes are derived based on the detection theory, i.e., maximum likelihood (ML), linear minimum mean square error (MMSE), successive interference cancellation (SIC), combining with the statistical analysis, i.e., Bayesian linear regression and Bayesian model comparison, in order to deal with the channel uncertainty, i.e., fading, correlations, thermal noise, multiple interference, and the impact of estimation errors.In the transmission schemes, the signal constellations are targeted to find a good trade off between the average transmit energy and the minimum Euclidean distance in the signal space. The proposed schemes, denoted by enhanced SM (ESM), introduce novel modulation/antenna combinations and use them as the information bits for transmission. The number of those combinations is the double or the quadruple of the number of active antenna indices (or index combinations) in conventional SM systems, and this increases the number of bits transmitted per channel use by one or two.The results of simulations show that good system performance can be achieved with the advanced MIMO techniques. Several examples are presented in this thesis to provide insights for the MIMO system designs
APA, Harvard, Vancouver, ISO, and other styles
4

Zhou, Zhou. "MIMO-OFDM Symbol Detection via Echo State Networks." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/95945.

Full text
Abstract:
Echo state network (ESN) is a specific neural network structure composed of high dimensional nonlinear dynamics and learned readout weights. This thesis considers applying ESN for symbol detection in multiple-input, multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. A new ESN structure, namely, windowed echo state networks (WESN) is introduced to further improve the symbol detection performance. Theoretical analysis justifies WESN has an enhanced short-term memory (STM) compared with the standard ESN such that WESN can offer better computing ability. Additionally, the bandwidth spent as the training set is the same as the demodulation reference signals defined in 3GPP LTE/LTE-Advanced systems for the ESN/WESN based symbol detection. Meanwhile, a unified training framework is developed for both comb and scattered pilot patterns. Complexity analysis demonstrates the advantages of ESN/WESN based symbol detector compared to conventional symbol detectors such as linear minimum mean square error (LMMSE) and sphere decoder when the system is employed with a large number of OFDM sub-carriers. Numerical evaluations show that ESN/WESN has an improvement of symbol detection performance as opposed to conventional methods in both low SNR regime and power amplifier (PA) nonlinear regime. Finally, it demonstrates that WESN can generate a better symbol detection result over ESN.
Artificial neural networks (ANN) are widely used in recognition tasks such as recommendation systems, robotics path planning, self-driving, video tracking, image classifications, etc. To further explore the applications of ANN, this thesis considers using a specific ANN, echo state network (ESN) for a wireless communications task: MIMO-OFDM symbol detection. Furthermore, it proposed an enhanced version of the standard ESN, namely, windowed echo state network (WESN). Theoretical analyses on the short term memory (STM) of ESN and WESN show that the later one has a longer STM. Besides, the training set size of this ESN/WESN based method is chosen the same as the pilot symbols used in conventional communications systems. The algorithm complexity analysis demonstrates the ESN/WESN based method performs with lower complexity compared with conventional methods, such as linear mean square error (LMMSE) and sphere decoding. Comprehensive simulations examine how the symbol detection performance can be improved by using ESN and its variant WESN when the transmission link is non-ideal.
APA, Harvard, Vancouver, ISO, and other styles
5

Perrins, Erik. "MULTI-SYMBOL NONCOHERENT DETECTION OF MULTI-H CPM." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/605816.

Full text
Abstract:
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Two receivers are presented for the general case of noncoherent detection of multi-h continuous phase modulation (CPM). Both receivers yield performance gains using multi-symbol observations. The first is an existing receiver [1, 2] which has previously been applied to PCM/FM [3] and is now applied to the ARTM Tier II telemetry waveform. The second receiver is presented for the first time in this paper. The existing noncoherent receiver is found to perform poorly (and with high complexity) for the ARTM Tier II case. For single-symbol observations, the new receiver outperforms conventional FMdemodulation for both telemetry waveforms, and for multi-symbol observation lengths its performance approaches that of the optimal coherent receiver. The performance is evaluated using computer simulations. Receiver performance is also evaluated using a simple channel model with varying carrier phase. The traditional FM demodulator approach is found to outperform both receivers as channel conditions worsen.
APA, Harvard, Vancouver, ISO, and other styles
6

Geoghegan, Mark. "EXPERIMENTAL RESULTS FOR MULTI-SYMBOL DETECTION OF PCM/FM." International Foundation for Telemetering, 2001. http://hdl.handle.net/10150/607605.

Full text
Abstract:
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada
It has been previously shown, through computer simulations, that a multiple symbol detector can provide substantial gains in detection efficiency (nearly 3 dB) over traditional PCM/FM detectors. This is accomplished by performing correlations over multiple symbol intervals to take advantage of the memory inherent in the continuous phase PCM/FM signal. This paper presents measured hardware results, from a prototype developed for the Advanced Range Telemetry (ARTM) Project, that substantiate the previously published performance and sensitivity predictions. Furthermore, this work confirms the feasibility of applying this technology to high-speed commercial and military telemetry applications.
APA, Harvard, Vancouver, ISO, and other styles
7

Waseem, Athar, and A. H. M. Sadath Hossain. "MIMO Channel Equalization and Symbol Detection using Multilayer Neural Network." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2345.

Full text
Abstract:
In recent years Multiple Input Multiple Output (MIMO) systems have been employed in wireless communication systems to reach the goals of high data rate. A MIMO use multiple antennas at both transmitting and receiving ends. These antennas communicate with each other on the same frequency band and help in linearly increasing the channel capacity. Due to the multi paths wireless channels face the problem of channel fading which cause Inter Symbol Interference (ISI). Each channel path has an independent path delay, independent path loss or path gain and phase shift, cause deformations in a signal and due to this deformation the receiver can detect a wrong or a distorted signal. To remove this fading effect of channel from received signal many Neural Network (NN) based channel equalizers have been proposed in literature. Due to high level non-linearity, NN can be efficient to decode transmitted symbols that are effected by fading channels. The task of channel equalization can also be considered as a classification job. In the data (received symbol sequences) spaces NN can easily make decision regions. Specifically, NN has the universal approximation capability and form decision regions with arbitrarily shaped boundaries. This property supports the NN to be introduced and perform the task of channel equalization and symbol detection. This research project presents the implementation of NN to be use as a channel equalizer for Rayleigh fading channels causing ISI in MIMO systems. Channel equalization has been done using NN as a classification problem. The equalizer is implemented over MIMO system of different forms using Quadrature Amplitude Modulation scheme (4QAM & 16QAM) signals. Levenberg-Marquardt (LM), One Step Secant (OSS), Gradient Descent (GD), Resilient backpropagation (Rprop) and Conjugate Gradient (CG) algorithms are used for the training of NN. The Weights calculated during the training process provides the equalization matrix as an estimate of Channel. The output of the NN provides the estimate of transmitted signals. The equalizer is assessed in terms of Symbol Error Rate (SER) and equalizer efficiency.
APA, Harvard, Vancouver, ISO, and other styles
8

Dye, Derek J. "Bandwidth and detection of packet length covert channels." Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5724.

Full text
Abstract:
Approved for public release; distribution is unlimited.
This thesis explores the detectability and robustness of packet length covert channels. We discovered that packet length covert channels, where a rogue user modulates the length of a Transport Control Protocol packet, can be detected while monitoring traffic of a large network. The bandwidth of these channels can be successfully estimated as well as the channels themselves detected using statistical inference. In addition, we observed that there is an inverse relationship between the volitionality in networks with respect to packet lengths and the detectability of these channels, and between packet length and channel bandwidth. For a large network like a college department, the bandwidth of a covert channel could be in the tens of megabytes over the course of a day.
APA, Harvard, Vancouver, ISO, and other styles
9

Wang, Yi. "Joint OFDM symbol detection and channel estimation over doubly selective channels." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121486.

Full text
Abstract:
Orthogonal Frequency Division Multiplexing (OFDM) is a promising technique for high data rate transmission, that is widely used in modern wireless communication systems because of its good performance over frequency selective channels. However OFDM systems are sensitive to channel time variation resulting in Inter-Carrier Interference (ICI), that without suitable detection methods can degrade performance. Channel State Information (CSI) is essential to various OFDM data detection schemes and its acquisition is a critical factor, in particular over time-varying channels. This work considers a technique for integrating the Kalman filter channel estimation with a version of Sphere Decoding (SD) adapted to OFDM detection. By modelling the OFDM system in frequency domain as a Multiple Input Multiple Output (MIMO) system, we derive a powerful SD technique for data detection. By approximating the channel matrix as banded, we are able to maintain a feasible complexity for SD and deliver competitive performance when compared to other existing scheme. For acquisition of CSI, the Basis Expansion (BE) method is used to model the time-varying channels and a Kalman filter is constructed for tracking. The Kalman filter employs decision-feedback from the SD, requiring only a low pilot symbol density, and hence improves bandwidth efficiency. The performance of this scheme is evaluated by Monte-Carlo computer simulations. Results show that compared with competing algorithm, this scheme provides performance gains. When it is used over moderate time-varying LTE channels, this scheme shows good performance even in the presence of carrier phase noise.
Le multiplexage par répartition en fréquence orthogonale (OFDM, pour Orthogonal Frequency Division Multiplexing) est une technique prometteuse pour la transmission de données à haut débit. Il est largement utilisé dans les systèmes de communication sans fil actuels en raison de ses bonnes performances sur les canaux sélectifs en fréquence. Toutefois, les systèmes reposant sur l'OFDM sont sensibles aux variations de temps de voie, qui entraînent un brouillage inter-porteuses (ICI, pour Inter-Carrier Interference). En l'absence de méthodes de détection appropriée, ce brouillage peut réduire les performances. Les informations d'état de canal (CSI, pour Channel State Information) constituent un élément essentiel des divers systèmes de détection de données basés sur l'OFDM et leur acquisition est un facteur crucial, surtout sur les canaux variables en temps. La présente examine une technique permettant d'intégrer l'évaluation de canaux reposant sur un filtre de Kalman à une variante du décodage par sphères (SD, pour Sphere Decoding) adaptée à la détection OFDM. En modélisant le système d'OFDM dans le domaine fréquentiel comme un système « entrées multiples, sorties multiples » (MIMO, pour Multiple Input Multiple Output), nous obtenons une puissante technique de SD pour la détection des données. En tenant pour acquis que la matrice de canal est une matrice bande, il est possible de maintenir une complexité recelant le potentiel pour une implantation réelle du SD et d'obtenir des performances concurrentielles comparativement à d'autres systèmes existants. En ce qui a trait à l'acquisition des CSI, on utilise la méthode de l'« expansion de base » (BE, pour Basis Expansion) pour modéliser les canaux variables en temps et on crée un filtre de Kalman pour le suivi des variations de temps des canaux. Le filtre de Kalman utilise les retours de décisions tirés du SD. Il ne nécessite ainsi qu'une faible densité de symboles pilotes, ce qui accroît l'optimisation de la bande passante. Les performances de ce système sont évaluées à l'aide de simulations informatiques reposant sur la méthode de Monte-Carlo. Les résultats montrent que par rapport à l'algorithme mis en concurrence, ce système permet des gains de performance. Quand il est utilisé sur des canaux LTE (Long Term Evolution) modérément variables en temps, ce système atteint une bonne performance, même en présence de brouillage de la phase des porteuses.
APA, Harvard, Vancouver, ISO, and other styles
10

Pentukar, Sai Kiran. "OCLEP+: One-Class Intrusion Detection Using Length of Patterns." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1496147438710588.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Detection of symbol length"

1

Dao, Joseph. A VLSI architecture for symbol-by-symbol detection. Ottawa: National Library of Canada = Bibliothèque nationale du Canada, 1992.

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

Khan, Zad. Lyndon length functions, R[real number symbol]-trees and hyperbolic length functions. Birmingham: University of Birmingham, 1992.

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

Divsalar, Dariush. Multiple symbol differential detection of uncoded and trellis coded MPSK. Pasadena, Calif: National Aeronautics and Space Administration, Jet Propulsion Laboratory, California Institute of Technology, 1990.

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

Cary, Paul L. The marijuana detection window: Determining the length of time cannabinoids will remain detectable in urine following smoking : a critical review of relevant research and cannabinoid detection guidance for drug courts. Alexandria, VA: National Drug Court Institute, 2006.

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

Erfanian, Javan A. *. Low-complexity parallel structures for symbol-by-symbol detection. 1989.

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

Probability of Symbol Error for Coherent and Non-Coherent Detection of M-ary Frequency-Shift Keyed (MFSK) Signals Affected by Co-Channel Interference and Additive White Gaussian Noise (AWGN) in a. Storming Media, 2000.

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

Menary, Richard. Keeping Track with Things. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198769811.003.0016.

Full text
Abstract:
The chapter begins with an evolutionary account of tracking systems, from simple detection systems to complex decoupled and highly flexible tracking systems. The important mediator is the role of the environment in providing the complexity, translucency, and hostility that produces the evolutionary pressures that result in more complex tracking systems. An evolutionary platform is provided for how modern humans could have come to innovate epistemic tracking tools (ETTs) for keeping track of salient features of the environment. Three examples of ETTs in action are given, ranging from highly iconic and contextual learning tools—such as the Mattang—to highly abstract and decoupled conventional symbol systems. Finally, it is argued that ETTs are compatible with a responsibilist-reliabilism since their correct deployment requires epistemic diligence and the reliable functioning of the tool itself. As such, a framework for understanding and exploring how we keep track with things has been given.
APA, Harvard, Vancouver, ISO, and other styles
8

Doyle, Arthur Conan. Sherlock Holmes. Selected Stories. Edited by Barry McCrea. Oxford University Press, 2014. http://dx.doi.org/10.1093/owc/9780199672066.001.0001.

Full text
Abstract:
‘Detection is, or ought to be, an exact science.’ For more than a century the Holmes stories have held a strange, almost inexplicable grip on the popular imagination. They are intimately associated with late Victorian and Edwardian society, yet curiously timeless in their appeal. The characters of Sherlock Holmes and Dr Watson, together with their housekeeper Mrs Hudson and their address at 221B Baker Street are as familiar today as when they made their first appearance in the late 1880s. The stories have been endlessly interpreted, adapted, and modernized, but still it is to Arthur Conan Doyle's originals that we return. This new selection of some of the best of them is designed to give readers a full sense of their world: the brooding fog of London, ruined heirs in creaking mansions, and hidden crimes in the farthest–flung corners of the British Empire. The stories take Holmes's career from its early days to its close, and include the book–length Sign of the Four. Barry McCrea's introduction investigates the currents that lie beneath their surface.
APA, Harvard, Vancouver, ISO, and other styles
9

de Graaf, Michiel A., Arthur JHA Scholte, Lucia Kroft, and Jeroen J. Bax. Computed tomography angiography and other applications of computed tomography. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199687039.003.0022.

Full text
Abstract:
Patients presenting with acute chest pain constitute a common and important diagnostic challenge. This has increased interest in using computed tomography for non-invasive visualization of coronary artery disease in patients presenting with acute chest pain to the emergency department; particularly the subset of patients who are suspected of having an acute coronary syndrome, but without typical electrocardiographic changes and with normal troponin levels at presentation. As a result of rapid developments in coronary computed tomography angiography technology, high diagnostic accuracies for excluding coronary artery disease can be obtained. It has been shown that these patients can be discharged safely. The accuracy for detecting a significant coronary artery stenosis is also high, but the presence of coronary artery atherosclerosis or stenosis does not imply necessarily that the cause of the chest pain is related to coronary artery disease. Moreover, the non-invasive detection of coronary artery disease by computed tomography has been shown to be related with an increased use of subsequent invasive coronary angiography and revascularization, and further studies are needed to define which patients benefit from invasive evaluation following coronary computed tomography angiography. Conversely, the implementation of coronary computed tomography angiography can significantly reduce the length of hospital stay, with a significant cost reduction. Additionally, computed tomography is an excellent modality in patients whose symptoms suggest other causes of acute chest pain such as aortic aneurysm, aortic dissection, or pulmonary embolism. Furthermore, the acquisition of the coronary arteries, thoracic aorta, and pulmonary arteries in a single computed tomography examination is feasible, allowing ‘triple rule-out’ (exclusion of aortic dissection, pulmonary embolism, and coronary artery disease). Finally, other applications, such as the evaluation of coronary artery plaque composition, myocardial function and perfusion, or fractional flow reserve, are currently being developed and may also become valuable in the setting of acute chest pain in the future.
APA, Harvard, Vancouver, ISO, and other styles
10

de Graaf, Michiel A., Arthur JHA Scholte, Lucia Kroft, and Jeroen J. Bax. Computed tomography angiography and other applications of computed tomography. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199687039.003.0022_update_001.

Full text
Abstract:
Patients presenting with acute chest pain constitute a common and important diagnostic challenge. This has increased interest in using computed tomography for non-invasive visualization of coronary artery disease in patients presenting with acute chest pain to the emergency department; particularly the subset of patients who are suspected of having an acute coronary syndrome, but without typical electrocardiographic changes and with normal troponin levels at presentation. As a result of rapid developments in coronary computed tomography angiography technology, high diagnostic accuracies for excluding coronary artery disease can be obtained. It has been shown that these patients can be discharged safely. The accuracy for detecting a significant coronary artery stenosis is also high, but the presence of coronary artery atherosclerosis or stenosis does not imply necessarily that the cause of the chest pain is related to coronary artery disease. Moreover, the non-invasive detection of coronary artery disease by computed tomography has been shown to be related with an increased use of subsequent invasive coronary angiography and revascularization, and further studies are needed to define which patients benefit from invasive evaluation following coronary computed tomography angiography. Conversely, the implementation of coronary computed tomography angiography can significantly reduce the length of hospital stay, with a significant cost reduction. Additionally, computed tomography is an excellent modality in patients whose symptoms suggest other causes of acute chest pain such as aortic aneurysm, aortic dissection, or pulmonary embolism. Furthermore, the acquisition of the coronary arteries, thoracic aorta, and pulmonary arteries in a single computed tomography examination is feasible, allowing ‘triple rule-out’ (exclusion of aortic dissection, pulmonary embolism, and coronary artery disease). Finally, other applications, such as the evaluation of coronary artery plaque composition, myocardial function and perfusion, or fractional flow reserve, are currently being developed and may also become valuable in the setting of acute chest pain in the future.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Detection of symbol length"

1

Nissel, Ronald. "Symbol Detection in High Speed Channels." In The Vienna LTE-Advanced Simulators, 39–60. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-0617-3_3.

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

Jin, Shi, Zhaobo Zhang, Krishnendu Chakrabarty, and Xinli Gu. "Hierarchical Symbol-Based Health-Status Analysis." In Anomaly-Detection and Health-Analysis Techniques for Core Router Systems, 85–113. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-33664-6_4.

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

Ahmed, Sohail, R. G. Maunder, Lie-Liang Yang, and Lajos Hanzo. "Iterative Detection of Three-Stage Concatenated IrVLC FFH-MFSK." In Near-Capacity Variable-Length Coding, 401–19. Chichester, UK: John Wiley & Sons, Ltd, 2010. http://dx.doi.org/10.1002/9780470666425.ch11.

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

Wespi, Andreas, Marc Dacier, and Hervé Debar. "Intrusion Detection Using Variable-Length Audit Trail Patterns." In Lecture Notes in Computer Science, 110–29. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/3-540-39945-3_8.

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

Ah-Soon, Christian. "A constraint network for symbol detection in architectural drawings." In Graphics Recognition Algorithms and Systems, 80–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/3-540-64381-8_41.

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

Suzuki, Toshinori, and Toshio Mizuno. "Multiple-symbol differential detection scheme for differential amplitude modulation." In Lecture Notes in Computer Science, 196–207. Berlin, Heidelberg: Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/3-540-57856-0_19.

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

Terrades, Oriol Ramos, and Ernest Valveny. "Line Detection Using Ridgelets Transform for Graphic Symbol Representation." In Pattern Recognition and Image Analysis, 829–37. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-540-44871-6_96.

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

Wang, Ge, Hong-Yi Yu, and Zhi-Xiang Shen. "An Improved Symbol Detection Algorithm Based on Expectation-Maximum." In Communications in Computer and Information Science, 467–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-53932-9_46.

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

Ziran, Zahra, Eleonora Bernasconi, Antonella Ghignoli, Francesco Leotta, and Massimo Mecella. "Accurate Graphic Symbol Detection in Ancient Document Digital Reproductions." In Document Analysis and Recognition – ICDAR 2021 Workshops, 147–62. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86198-8_12.

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

He, Zhongwei, Wei Lu, and Wei Sun. "Improved Run Length Based Detection of Digital Image Splicing." In Digital Forensics and Watermarking, 349–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-32205-1_28.

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

Conference papers on the topic "Detection of symbol length"

1

Niemela, V., M. Hamalainen, and J. Iinatti. "On IEEE 802.15.6 UWB symbol length for energy detector receivers' performance with OOK and PPM." In 2013 7th International Symposium on Medical Information and Communication Technology (ISMICT 2013). IEEE, 2013. http://dx.doi.org/10.1109/ismict.2013.6521694.

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

Lita, Catalin-Valeriu. "On Complexity of the Detection Problem for Bounded Length Polymorphic Viruses." In 2016 18th International Symposium on Symbolic and Numeric Algorithms for Scientific Computing (SYNASC). IEEE, 2016. http://dx.doi.org/10.1109/synasc.2016.064.

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

Tajer, Ali, Aria Nosratinia, and Naofal Al-Dhahir. "MMSE Infinite Length Symbol-by-Symbol Linear Equalization Achieves Full Diversity." In 2007 IEEE International Symposium on Information Theory. IEEE, 2007. http://dx.doi.org/10.1109/isit.2007.4557467.

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

Lado, Gustavo, and Enrique Carlos Segura. "Effective Vector Representations for Variable Length Symbol Sequences." In Seventh International Conference on Computer Science, Engineering and Information Technology. Academy & Industry Research Collaboration Center (AIRCC), 2017. http://dx.doi.org/10.5121/csit.2017.70604.

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

Sudalaiyandi, Shanthi, Tuan-Anh Vu, Hakon A. Hjortland, Oivind Nass, and Tor Sverre Lande. "Continuous-time single-symbol IR-UWB symbol detection." In 2012 IEEE 25th International SOC Conference (SOCC). IEEE, 2012. http://dx.doi.org/10.1109/socc.2012.6398347.

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

Brunt, S. "Symbol synchronisation slip detection." In IEE Colloquium on New Synchronisation Techniques for Radio Systems. IEE, 1995. http://dx.doi.org/10.1049/ic:19951400.

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

Chun-Feng Wu, Tzu-Fan Hsu, and Wen-Whei Chang. "Iterative symbol decoding of convolutionally-encoded variable-length codes." In 2011 8th International Conference on Information, Communications & Signal Processing (ICICS 2011). IEEE, 2011. http://dx.doi.org/10.1109/icics.2011.6174312.

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

Ali, Ali Ramadan, Ali Alsaih, Tariq Jamil Khanzada, Jan Machac, and Abbas Omar. "Adaptive symbol length for OFDM systems in doubly selective channels." In 2009 Asia Pacific Microwave Conference - (APMC 2009). IEEE, 2009. http://dx.doi.org/10.1109/apmc.2009.5384417.

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

Hung-Tsai Wu, Chih-Hsien Lin, and Wen-Whei Chang. "Symbol-based joint decoding of convolutionally encoded variable-length codes." In 2012 12th International Conference on ITS Telecommunications (ITST). IEEE, 2012. http://dx.doi.org/10.1109/itst.2012.6425154.

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

Epishkina, Anna, and Konstantin Kogos. "Protection from binary and multi-symbol packet length covert channels." In SIN '15: The 8th International Conference on Security of Information and Networks. New York, NY, USA: ACM, 2015. http://dx.doi.org/10.1145/2799979.2799994.

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

Reports on the topic "Detection of symbol length"

1

Chavez, Jorge L., Nancy Kelley-Loughnane, Morley O. Stone, and Robert I. MacCuspie. Colorimetric Detection with Aptamer-Gold Nanoparticle Conjugates: Effect of Aptamer Length on Response. Fort Belvoir, VA: Defense Technical Information Center, November 2012. http://dx.doi.org/10.21236/ada576582.

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

Stromswold, D. C., A. J. Peurrung, and R. J. Arthur. Feasibility study for transuranic nuclide measurement on long-length contaminated equipment using neutron detection. Office of Scientific and Technical Information (OSTI), October 1995. http://dx.doi.org/10.2172/123213.

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

Quinn, Meghan. Geotechnical effects on fiber optic distributed acoustic sensing performance. Engineer Research and Development Center (U.S.), July 2021. http://dx.doi.org/10.21079/11681/41325.

Full text
Abstract:
Distributed Acoustic Sensing (DAS) is a fiber optic sensing system that is used for vibration monitoring. At a minimum, DAS is composed of a fiber optic cable and an optic analyzer called an interrogator. The oil and gas industry has used DAS for over a decade to monitor infrastructure such as pipelines for leaks, and in recent years changes in DAS performance over time have been observed for DAS arrays that are buried in the ground. This dissertation investigates the effect that soil type, soil temperature, soil moisture, time in-situ, and vehicle loading have on DAS performance for fiber optic cables buried in soil. This was accomplished through a field testing program involving two newly installed DAS arrays. For the first installation, a new portion of DAS array was added to an existing DAS array installed a decade prior. The new portion of the DAS array was installed in four different soil types: native fill, sand, gravel, and an excavatable flowable fill. Soil moisture and temperature sensors were buried adjacent to the fiber optic cable to monitor seasonal environmental changes over time. Periodic impact testing was performed at set locations along the DAS array for over one year. A second, temporary DAS array was installed to test the effect of vehicle loading on DAS performance. Signal to Noise Ratio (SNR) of the DAS response was used for all the tests to evaluate the system performance. The results of the impact testing program indicated that the portions of the array in gravel performed more consistently over time. Changes in soil moisture or soil temperature did not appear to affect DAS performance. The results also indicated that time DAS performance does change somewhat over time. Performance variance increased in new portions of array in all material types through time. The SNR in portions of the DAS array in native silty sand material dropped slightly, while the SNR in portions of the array in sand fill and flowable fill material decreased significantly over time. This significant change in performance occurred while testing halted from March 2020 to August 2020 due to the Covid-19 pandemic. These significant changes in performance were observed in the new portion of test bed, while the performance of the prior installation remained consistent. It may be that, after some time in-situ, SNR in a DAS array will reach a steady state. Though it is unfortunate that testing was on pause while changes in DAS performance developed, the observed changes emphasize the potential of DAS to be used for infrastructure change-detection monitoring. In the temporary test bed, increasing vehicle loads were observed to increase DAS performance, although there was considerable variability in the measured SNR. The significant variation in DAS response is likely due to various industrial activities on-site and some disturbance to the array while on-boarding and off-boarding vehicles. The results of this experiment indicated that the presence of load on less than 10% of an array channel length may improve DAS performance. Overall, this dissertation provides guidance that can help inform the civil engineering community with respect to installation design recommendations related to DAS used for infrastructure monitoring.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Detection of symbol length' for particular source types:
Journal articles Dissertations / Theses
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