فهرست مطالب

Majlesi Journal of Telecommunication Devices
Volume:12 Issue: 1, Mar 2023

  • تاریخ انتشار: 1401/12/22
  • تعداد عناوین: 7
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  • Javad Nouri Pour, MohammadAli Pourmina *, MohamadNaser Moghaddasi, Behbod Ghalamkari Pages 1-6

    In this paper, a new method for estimating the tumor's location is presented; the technique is based on the arrangement of sensors and received wave changes. A new method has been developed for locating the return signal from the tumor. The main idea is that the location of the tumor is randomly assumed. And then estimates the location of the tumor. It presents a phase event. Various articles have used a combination of these methods to shape different issues. However, these methods have not been used to estimate tumor location. In this article, two types of wavelengths are used; the transmitter node first sends a signal with a specific frequency, it is assumed that the reflection is almost complete. Therefore, according to the reviews of the tumor signal, we find that the tumor is in the region of intensification, i.e., the dimensions of the tumor are in the order of the transmitted wavelength. Then, by changing the frequency, the signal passes through the tumor. The signal passing through the tumor (according to "Snell's" law) fails; that is, the received signal is received with angular deviation and delay. An estimator is suggested by the maximum likelihood maximum (MLE). The estimators have a nonlinear form. We use the SD reduction slope algorithm to LS linear search algorithm for optimizations.

    Keywords: Tumor, AOA, Maximum Probability, Signal angle deviation, breast tumor
  • Saeed Talati, Pouria Etezadifar *, MohammadReza Hassani Ahangar, Mahdi Molazade Pages 7-15

    Information security is currently one of the most important issues that have been considered by many researchers. The purpose of Steganography is to hide hidden messages in a non-secret file. In general, information Steganography is a method of secure communication that aims to hide data so that no data appears to be hidden. The principle of Steganography is to use spaces from the information carrier that do not harm the identity of the carrier.  By Steganography information from unauthorized recipients, the information is hidden and hidden inside it without harming the signals. This information may be transmitted around us and wherever any file is sent. It may contain very dangerous content for the security of the space in which we live. Audio signals are very used for steganography because Digital audio signals have higher redundancy and higher data transfer speeds, making them suitable for use as a cover. The LPC10, CELP, and MELP audio standards are widely used in audio and speech processing and are powerful high-quality speech coding methods that provide highly accurate estimates of audio parameters and are widely used in communications. Therefore, since considering that these audio standards are used in commercial and military telecommunication systems, they can be considered a suitable platform for sending the following message of audio content. We try to carefully examine these standards and the audio Steganography done in these standards.

    Keywords: Steganography, Audio Signal, Coding, LSB
  • Abbasgholi Pashaei, MohammadEsmaeil Akbari *, Mina Zolfy Lighvan, Asghar Charmin Pages 17-28

    Distributed Denial of Service (DDoS) attacks are a significant threat, especially for the Internet of Things (IoT). One approach that is practically used to protect the network against DDoS attacks is the honeypot. This study proposes a new adversarial Deep Reinforcement Learning (DRL) model that can deliver better performance using experiences gained from the environment. Further regulation of the agent's behavior is made with an adversarial goal. In such an environment, an attempt is made to increase the difficulty level of predictions deliberately. In this technique, the simulated environment acts as a second agent against the primary environment. To evaluate the performance of the proposed method, we compare it with two well-known types of DDoS attacks, including NetBIOS and LDAP. Our modeling overcomes the previous models in terms of weight accuracy criteria (> 0.98) and F-score (> 0.97). The proposed adversarial RL model can be especially suitable for highly unbalanced datasets. Another advantage of our modeling is that there is no need to segregate the reward function.

    Keywords: intrusion detection, Honeypot, Markov Decision Process, adversarial learning
  • Hossein Rahimi, Mahmoud Nikoufard *, Mojtaba Dehghani Firouzabadi Pages 29-35
    This paper aims to investigate the enhancement of Kerr nonlinear performance caused by more optical confinement and longer propagation length due to different metal-cap wedge-shaped hybrid plasmonic waveguide geometric parameters. In this work, we will focus on Kerr nonlinear effect, and analyze how the different waveguide geometries can enhance this effect. Our theoretical investigation shows that the presented nonlinear wedge-shaped hybrid plasmonic waveguide structure with a wedge-shaped gap is suitable for photonic integrated circuits based on the hybrid plasmonic passive waveguide, and is a suitable candidate for the photonic devices at nano-scales with nonlinearity.  It is also found that the investigated structure can have a longer propagation length of 2120 mm at a 10 nm thick nonlinear dielectric. The minimum effective mode area of the investigated structure is 0.0263 mm2 and the maximum nonlinear coefficient is . Also, the confinement factor of the DDMEBT layer is calculated by changing the wedge angle . It is found that the surface mode has a maximum confinement factor of 0.33 when . The modal and nonlinear properties of the hybrid plasmonic waveguides were analytically determined as well by using the finite element method (FEM). Simulation results show that the wedge-shaped hybrid plasmonic waveguide provides good performance for nonlinear applications such as optical switching at the optical wavelength of .
    Keywords: Plasmonic, Kerr effect, Wedge shape, nonlinear coefficient, effective area, confinement factor, Fig. of Merit
  • Farzaneh Kheirali, MohammadHossein Madani * Pages 37-42

    As a result of resource constraints in each generation of wireless systems, new technologies should be used in order to obtain maximum system efficiency. The combination of Adaptive Modulation and Coding (AMC) with Generalized Frequency Division Multiplexing (GFDM) is a promising technique which efficiently optimizes the data rate, increases the capacity and reduces Bit Error Rate (BER) of the systems, which are primary goals of each generation of wireless networks. In paper, we primarily analyze multicarrier GFDM performance based on adaptive modulation using a discrete rate, then examine a variable power transmission scheme and finally find the form of rate and power which maximizes the spectral efficiency. The results show that significant improvement in terms of spectral efficiency and BER can be achieved demonstrating the superiority of the proposed AMC scheme in comparison with nonadaptive transmission schemes. Therefore, the presented system can be used in next generation cellular networks with higher capacity.

    Keywords: Next Generation Cellular Network, Spectral efficiency, AMC, GFDM, Convolutional Coding
  • Zohreh Dorrani * Pages 43-47
    Road detection from high-resolution satellite images using deep learning is proposed in this article. The VGG19 architecture, which is one of the deep convolutional neural network architectures, is used in the proposed method. To detect the road, two steps are implemented. To achieve high accuracy, image segmentation is done in the first step. At this stage, based on the semantic division, the objects whose area is small are removed. In the second stage, edge detection of images combines two techniques of segmentation and edge detection to improve road detection. Considering the good accuracy of the VGG19 architecture and the need for few parameters, the obtained results are favorable. To check the performance of the proposed method, the IoU criterion was used. The values obtained for this criterion show an improvement of more than 80%. While this criterion is less than 80% for the compared methods. The obtained results can be used for the purposes of digital mapping, transportation management and many other applications.
    Keywords: Convolutional neural networks, deep learning, Edge detection, road segmentation, Satellite Images, VGG19
  • Noushin Dadashzadeh *, Elnaz Poorreza, Vahide Mohadesi Pages 49-52
    In this article, the simulation of the physical phenomenon of coaxial corona discharge in air, in DC mode using the finite element method is discussed. Basically, to optimize the production process of ionized gas and any other physical phenomenon, we model and simulate the phenomenon. To simulate this phenomenon, from two cylindrical electrodes, one inside (cathode) and the other outside (anode), the radius of the inner electrode is 100 microns and the distance between the electrodes is 10 cm. A constant voltage of 50 kV is applied to the inner electrode. The outer electrode is considered the ground. Our emphasis is on the formation of charged particles and their behavior in the resulting electric field. In order to avoid the complexity of the problem and save the simulation time, we model in a one-dimensional way and in the results extract the above phenomenon in a two-dimensional way. The gas temperature is 640 K and the air density is considered constant.
    Keywords: Corona DC discharge, Plasma, power systems, Finite Element Method, Ionisation