Telfor Journal Vol.11 No.2 (2019)
Content
Editorial 
Editor-in-Chief:
Prof. Dr Đorđe Paunović
Traffic Modelling Challenges on 10 Gbit/s Links using Netmap Platform
H. Redžović, Z. Čiča, and A. Smiljanić- Topic:
- Telecommunications Networks
- Abstract
- Network devices are using a growing number of 10 Gbit/s links. Such throughput upgrade imposes new challenges on creating high-speed packet generators that can provide real network conditions. Traffic generators implemented as software solutions have challenges in achieving a required performance, as they are commonly using a kernel network stack for packet I/O. We describe different techniques for implementing the Poisson and on-off traffic model in a software-based traffic generator that is using netmap API as fast packet I/O.
- Keywords
- Traffic Generators, netmap API, IP traffic models.
- Full Text
- Traffic Modelling Challenges on 10 Gbit/s Links using Netmap Platform
- Page(s)
- 78-83
- Doi
- 10.5937/telfor1902078R
An Investigation of a New GSM Systems Jamming Technique without Existing Connections Disruption
M. Đ. Mileusnić, P. M. Petrović, B. R. Pavić, V. B. Marinković-Nedelicki, V. S. Matić, and A. V. Lebl
- Topic:
- Radio Communications
- Abstract
- This paper presents a new method for jamming of GSM communications. The aim is to decrease voice connection quality, thus disabling users to understand each other, while keeping established connections. The jamming method parameters depend on the algorithm characteristics implemented in SACCH frame. It is proved for three mobile telephony codecs that it is possible to reach unsatisfactory voice connection quality MOS<2 due to jamming of a GSM communications channel. Errors in data transmission during the periods without jamming also cause voice connection quality impairment and this influence is analyzed. The method performances are compared to other solutions.
- Keywords
- E-model, GSM system jamming, jamming rate, SACCH frame.
- Full Text
- An Investigation of a New GSM Systems Jamming Technique without Existing Connections Disruption
- Page(s)
- 84-89
- Doi
- 10.5937/telfor1902084M
OpenCL/CUDA Algorithms for Parallel Decoding of any Irregular LDPC Code using GPU
J. Broulim, A. Ayriyan, H. Grigorian, and V. Georgiev
- Topic:
- Communication Theory
- Abstract
- This article provides a scalable parallel approach of an iterative LDPC decoder. The proposed approach can be implemented in applications supporting massive parallel computing. The proposed mapping is suitable for decoding any irregular LDPC code without the limitation of the maximum node degree. The implementation of the LDPC decoder with the use the OpenCL and CUDA frameworks is discussed and a performance evaluation is given at the end of this contribution.
- Keywords
- Error correction, GPU, LDPC, parallel decoder.
- Full Text
- OpenCL/CUDA Algorithms for Parallel Decoding of any Irregular LDPC Code using GPU
- Page(s)
- 90-95
- Doi
- 10.5937/telfor1902090B
Improved Model of the Circularly Polarized Patch Antenna Array at 24 GHz for Radar Applications
I. Radnovic, B. Jokanovic, and A. Boryssenko
- Topic:
- Applied Electromagnetics
- Abstract
- The paper presents the improved design of the novel circularly polarized patch antenna array operating at ISM band 24.05-24.25 GHz. The antenna array consists of 24 identical truncated patches which are serially fed through the microstrip line. The antenna is a travelling-wave array with exponential power distribution which provides very good side lobe suppression of 30 dB in the entire operating band making it suitable for automotive radar applications. Simulated axial ratio is below 3dB in the range (24.06-24.26) GHz, the antenna gain is greater than 17.2 dBi, cross polarization is better than 15 dB and return loss is greater than 15 dB in the entire ISM band.
- Keywords
- Antenna array, circularly polarized patch antenna, exponential power distribution, axial ratio
- Full Text
- Improved Model of the Circularly Polarized Patch Antenna Array at 24 GHz for Radar Applications
- Page(s)
- 96-101
- Doi
- 10.5937/telfor1902096R
Using the Random Components of the Jitter of Speech Pitch Period to Assess the State of the User of Social-Cyber-Physical System
E. Pakulova, I. Vatamaniuk, V. Budkov, R. Iakovlev, and M. Nosov
- Topic:
- Speech Processing
- Abstract
- Socio-cyber-physical systems are focused on perceptual interaction with users and involve analyzing and translating his or her physiological and psycho-emotional state. An actual scientific problem is to determine the latter basing on the user’s speech signal. In particular, it can be solved relying on investigating the jitter of the speech pitch period. In this paper we propose an algorithm that allows one to improve the noise immunity of determining the pitch period of speech signal and a method of jitter determination based on averaging the change of the pitch period relatively to the current value. We also propose an algorithm for separating periodic and random pitch jitter based on using the discrete Fourier transform on the sequence of the pitch periods with the presence of unknown values in the unvoiced speech frames. Simulation shows that the proposed approach of filling the unknown values of pitch period has better results compared to the existing methods based on interpolation of the nearest known values.
- Keywords
- Frequency estimation, Jitter, Pitch control, Speech analysis, Speech coding, Speech synthesis.
- Full Text
- Using the Random Components of the Jitter of Speech Pitch Period to Assess the State of the User of Social-Cyber-Physical System
- Page(s)
- 102-107
- Doi
- 10.5937/telfor1902102P
System for Measuring Finger Force Profiles for Dexterity Assessment
M. M. Badža, M. M. Novičić, M. Đurić-Jovičić, M. M. Janković, and M. B. Popović
- Topic:
- Software Tools and Applications
- Abstract
- We propose a novel system for measuring finger force profiles for dexterity assessment. The system consists of a software application and encased hardware. The sensing part of the system consists of ten high sensitivity strain gage force sensors, one for each finger. The developed application controls turning ON/OFF of the LEDs (each LED corresponds to one finger) to signalize the user which finger should press the corresponding strain gage force sensor. Linearity, repeatability, and sensitivity to position pressure of the strain gage force sensors were tested to prove the system reliability. The potential usage of the system with the assessment of quantitative parameters was demonstrated on two healthy subjects.
- Keywords
- Finger dexterity, Finger force, Strain gage force sensor, Quantitative assessment.
- Full Text
- System for Measuring Finger Force Profiles for Dexterity Assessment
- Page(s)
- 108-113
- Doi
- 10.5937/telfor1902108B
Quality Assurance in Big Data Analytics: An IoT Perspective
N. A. Fernandes and R. Wagh
- Topic:
- Software Tools and Applications
- Abstract
- Emergence of IoT as one of the key data contributors in a big data application has presented new data quality challenges and has necessitated for an IoT inclusive data validation ecosystem. Standardized data quality approaches and frameworks are available for data obtained for a variety of sources like data warehouses, webblogs, social media, etc. in a big data application. Since IoT data differs significantly from other data, challenges in ensuring the quality of this data are also different and thus a specially designed IoT data testing layer paves its way in. In this paper, we present a detailed review of existing data quality assurance practices used in big data applications. We highlight the requirement for IoT data quality assurance in the existing framework and propose an additional data testing layer for IoT. The data quality aspects and possible implementation models for quality assurance contained in the proposed layer can be used to construct a concrete set of guidelines for IoT data quality assurance.
- Keywords
- Big Data, Internet of Things (IoT), Data Quality, Data Testing, IoT data Validation, Quality of Service (QoS).
- Full Text
- Quality Assurance in Big Data Analytics: An IoT Perspective
- Page(s)
- 114-118
- Doi
- 10.5937/telfor1902114A
The TELFOR Journal appreciates the support received from the reviewers. The following is the alphabetic list of the reviewers who have submitted one or more reviews for the current volume of the TELFOR Journal.
Milan Bjelica, Milana Bojanić, Jelena Ćertić, Zoran Čiča, Nebojša Dončov, Borislav Đorđević, Dejan Drajić, Dragomir El Mezeni, Ana Gavrovska, Predrag Ivaniš, Nikša Jakovljević, Miloš Janjić, Milica Janković, Siniša Jovanović, Anamarija Juhas, Ivan Kaštelan, Mladen Koprivica, Nenad Krajnović, Miroslav Lutovac, Maja Lutovac Banduka, Nemanja Maček, Nataša Maksić, Nebojša Malešević, Dejan Milić, Nenad Milošević, Milan Narandžić, Jelena Nikolić, Zorica Nikolić, Milorad Paskaš, Miloš Pavlović, Slavche Pejoski, Miroslav Perić, Cristian Perra, Miloš Petrović, Zaharije Radivojević, Milutin Radonjić, Milutin Radonjić, Andreja Samčović, Tomislav Šekara, Mirjana Stojanović, Perica Štrbac, Miodrag Tasić, Nikola Tomašević, Branimir Trenkić, Branimir Trenkić, Miloš Vujisić, Marija Zajeganović, Amela Zeković