15 research outputs found

    Automatic modulation classification based deep learning with mixed feature

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    The automatic modulation classification (AMC) plays an important and necessary role in the truncated wireless signal, which is used in modern communications. The proposed convolution neural network (CNN) for AMC is based on a method of feature expansion by integrating I/Q (time form) with r/Ɵ (polar form) in order to take advantage of two things: first, feature expansion helps to increase features; the second is that converting to polar form helps to increase classification accuracy for higher order modulation due to diversity in polar form. CNN consists of six blocks. Each block contains symmetric and asymmetric filters, as well as max and average pooling filters. This paper uses DeepSig: RadioML which is a dataset of 24 modulation classes. The proposed network has outperformed many recent papers in terms of classification accuracy for 24 modulation types, with a classification accuracy of up to 96.06 at an SNR=20 dB

    Modulation mode detection and classification for in-vivo nano-scale communication systems operating in terahertz band

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    This paper initiates the efforts to design an intelligent/cognitive nano receiver operating in terahertz band. Specifically, we investigate two essential ingredients of an intelligent nano receiver—modulation mode detection (to differentiate between pulse-based modulation and carrier-based modulation) and modulation classification (to identify the exact modulation scheme in use). To implement modulation mode detection, we construct a binary hypothesis test in nano-receiver’s passband and provide closed-form expressions for the two error probabilities. As for modulation classification, we aim to represent the received signal of interest by a Gaussian mixture model (GMM). This necessitates the explicit estimation of the THz channel impulse response and its subsequent compensation (via deconvolution). We then learn the GMM parameters via expectation–maximization algorithm. We then do Gaussian approximation of each mixture density to compute symmetric Kullback–Leibler divergence in order to differentiate between various modulation schemes (i.e., M{M} -ary phase shift keying and M{M} -ary quadrature amplitude modulation). The simulation results on mode detection indicate that there exists a unique Pareto-optimal point (for both SNR and the decision threshold), where both error probabilities are minimized. The main takeaway message by the simulation results on modulation classification is that for a pre-specified probability of correct classification, higher SNR is required to correctly identify a higher order modulation scheme. On a broader note, this paper should trigger the interest of the community in the design of intelligent/cognitive nano receivers (capable of performing various intelligent tasks, e.g., modulation prediction, and so on)

    Compact automatic modulation recognition using over-the-air signals and FOS features

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    The recent deployment of automatic modulation recognition (AMR) for cognitive radio (CR) systems has significantly enhanced spectrum sensing capabilities. The utilization of real-time over-the-air digital radio frequency (RF) data for the development of a digital spectrum sensing model based on the automatic modulation classification (AMC) is presented in this study as a step for incorporating opportunistic spectrum sensing onto the NomadicBTS architecture. Some digital modulation techniques were studied for second- generation (2G) through fourth-generation (4G) technology. The raw RF signal dataset was digitized and curated, while non-complex first-order statistical (FOS) features were used with algorithms based on the Scaled conjugate gradient (SCG) and Levenberg-Marquardt (LM) to find the best learning algorithm for the generated AMR model. The results show that the developed AMR model has a very high likelihood of correctly classifying signals, with distinct patterns for each of the features of FOS. The results are compared to reveal a least mean square error (MSE) of 0.0131 with a maximum accuracy of 93.5 percent when the model was trained with seventy (70) neurons in the hidden layer using the LM method. The best model's accuracy will allow for the most precise identification of spectrum holes in the bands under consideratio

    Research on Ship Classification using Faster Region Convolutional Neural Network for Port Security

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    Huvudsyftet med studien var att se i vilken grad det gÄr att finna samarbeten genom material- och/eller energiutbyten mellan nÀrliggande anlÀggningar inom skogsindustrin i Sverige. Genom att göra en inventering av vilka anlÀggningar som finns inom skogsindustrin och sedan kontakta dessa, sammanstÀlldes en lista över de olika anlÀggningarna och deras olika samarbeten. Inventeringen gjordes med hjÀlp av olika branschorganisationer samt sökmotorer pÄ Internet. Utöver detta besöktes ocksÄ fyra intressanta fall för att ge en inblick i hur dessa samarbeten kan se ut. Studien visar pÄ att den hÀr typen av samarbeten existerar inom skogsindustrin och att drygt en tredjedel av de studerade anlÀggningarna har nÄgon form av samarbeten rörande dessa frÄgor. Detta pekar pÄ att man inom skogsindustrin Àr lÄngt framme nÀr det gÀller resursutnyttjande och att möjligheten att minimera sin energi- och materialanvÀndning hela tiden Àr en relevant frÄga. Det finns med stor sannolikhet Ànnu fler sÄdana samarbeten som inte framkommit vid undersökningen och en intressant aspekt Àr att vid de besök som gjordes upptÀcktes samarbeten som inte uppmÀrksammats vid tidigare kontakter. Av de 152 tillfrÄgade anlÀggningarna i inventeringen erhölls svar frÄn 117 stycken vilket tyder pÄ att det finns ett stort intresse för dessa frÄgor inom skogsindustrin. Flera av de anlÀggningar som inte hade nÄgra samarbeten kring dessa frÄgor svarade ocksÄ att de hela tiden undersöker möjligheten till att inleda sÄdana. MÄnga av samarbetena rörande dessa frÄgor kretsar kring leveranser av el och Änga samt spÄn och flis men en del andra intressanta samarbeten har ocksÄ framkommit. Exempelvis anvÀnds slam frÄn bioreningsdammar till brÀnsle, jordförbÀttringsmedel och som tÀckmaterial vid deponier. Sammanfattningsvis tyder detta pÄ att skogsindustrin ligger lÄngt framme gÀllande dessa frÄgor men att det fortfarande finns mer att göra om energi- och materialanvÀndningen och dÀrigenom den negativa miljöpÄverkan ska minimeras.The aim and objective with this study was to investigate to what extent co-operation through material and energy exchange between adjacent industries among the forest industry in Sweden could be found. First, an inventory of the industries in the forest industry was conducted. Secondly, each company was contacted with questions concerning this issue. Complementary field studies of four specific cases were conducted in order to give an insight to how these co-operations may function in reality. The result of this study illustrates that co-operations among the industries exist in the forest industry sector as more than a third of the investigated industries has some kind of co-operation regarding material and energy exchange with adjacent industries. A total number of 152 industries were identified during the inventory phase and 117 of those industries participated in the study with their own answers. This high participation rate enhances the impression that these are important questions to the forest industry sector. Numerous of the co-operations mentioned revolve around electricity, steam, and by products from sawmills, like woodchips and sawdust. Nevertheless, a few other interesting co-operations have also been revealed during the study, for example; sludge from some of the pulp mills are used as fuel, soil fertilizer and as covering material at landfills. An interesting point is that co-operations, which not were discovered during the earlier correspondence with the industries, in fact were revealed during the field studies. Therefore, the probability that there are more existing co-operations between adjacent industries than the findings in the study reveals, are high. To sum up, this shows that the forest industry is well in advance regarding co-operation through material and energy exchange between adjacent industries. However, there is still a lot to be done if the negative effect on the environment from the forest industry should be minimised
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