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1

Skorelowanie metryk QoS dla usługi przeglądania stron internetowych w sieciach mobilnych LTE

Zmysłowski Dariusz, Kelner Jan M.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2023

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nr 4

61--64

PL

Nowoczesne sieci komórkowe zapewniają do stęp do różnorodnych usług. Z jednej strony operatorzy sieci komórkowych (MNO) są zobowiązani do zapewnienia odpowiedniego zasięgu sieci. Z drugiej strony usługi powinny być świadczone na odpowiednim poziomie. W tym artykule przedstawiamy analizę korelacyjną metryk jakości usług (QoS) i parametrów sygnału radiowego dla scenariusza przeglądania stron internetowych. Niniejsze badanie bazują na kampanii pomiarowej przeprowadzonej w okolicach Warszawy dla dwóch MNO.

EN

Modern mobile networks provide access to a variety of services. On the one hand, mobile network operators (MNOs) are required to ensure adequate network coverage. On the other hand, the provided services should be performed at an appropriate level. This paper presents a correlation analysis of quality of service (QoS) metrics and radio signal parameters for a web browsing scenario. This research is based on the measurement campaign carried out in the vicinity of Warsaw for two MNOs.

2

LTE network performance evaluation: A comparative study of planned and deployed networks

Krasniqi Bujar, Bojku Margarite, Prebreza Bahri

Przegląd Elektrotechniczny

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2023

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R. 99, nr 10

30--33

EN

This paper examines the comparison between the measured values and the defined interval for the selected parameters shows that they are within the acceptable range. However, differences in coverage are observed when comparing Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ), Signal to Interference-Noise Ratio (SINR), and throughput, mainly due to weaker resolution maps and changes in the infrastructure that have been continuously happening in that part of Prishtina.

PL

Ten artykuł analizuje porównanie między wartościami zmierzonymi a zdefiniowanym przedziałem dla wybranych parametrów, co pokazuje, że mieszczą się one w akceptowalnym zakresie. Jednakże zaobserwowano różnice w pokryciu podczas porównywania Mocy Odebranego Sygnału Referencyjnego (RSRP), Jakości Odebranego Sygnału Referencyjnego (RSRQ), Stosunku Sygnału do Zaburzeń i Szumów (SINR) oraz przepustowości, głównie z powodu słabszych map rozdzielczości oraz zmian w infrastrukturze, które ciągle mają miejsce w tej części Prisztiny.

3

Performance Investigation of High-Speed Train OFDM Systems under the Geometry-Based Channel Model

Do Viet Ha, Trinh Thi Huong, Nguyen Thanh Hai

International Journal of Electronics and Telecommunications

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2021

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Vol. 67, No. 3

451--457

EN

The high-speed of train (HST) in combination with the high carrier frequency of HST systems leads to the severe inter carrier interference (ICI) in the HST orthogonal frequency division multiplexing (HST-OFDM) systems. To avoid the complexity in OFDM receiver design for ICI eliminations, the OFDM system parameters such as symbol duration, signal bandwidth, and the number of subcarriers should be chosen appropriately. This paper aims to propose a process of HST-OFDM system performance investigation to determine these parameters in order to enhance spectral efficiency and meet a given quality-of-service (QoS) level. The signal-to-interference-plus-noise ratio (SINR) has been used as a figure of merit to analyze the system performance instead of signal-to-noise ratio (SNR) as most of recent research studies. Firstly, using the non-stationary geometry-based stochastic HST channel model, the SINR of each subcarrier has been derived for different speeds of the train, signal bandwidths, and number of subcarriers. Consequently, the system capacity has been formulated as the sum of all the single channel capacity from each sub-carrier. The constraints on designing HST-OFDM system parameters have been thoughtfully analyzed using the obtained expressions of SINR and capacity. Finally, by analyzing the numerical results, the system parameters can be found for the design of HST-OFDM systems under different speeds of train. The proposed process can be used to provide hints to predict performance of HST communication systems before doing further high cost implementations as hardware designs.

4

Next Generation Dynamic Inter-Cellular Scheduler

Yağcıoğlu Mert, Bayat Oğuz

International Journal of Electronics and Telecommunications

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2019

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Vol. 65, No. 3

441--448

EN

Orthogonal frequency division multiple access (OFDMA) in Long Term Evolution (LTE) can effectively eliminate intra-cell interferences between the subcarriers in a single serving cell. But, there is more critical issue that, OFDMA cannot accomplish to decrease the inter-cell interference. In our proposed method, we aimed to increase signal to interference plus noise ratio (SINR) by dividing the cells as cell center and cell edge. While decreasing the interference between cells, we also aimed to increase overall system throughput. For this reason, we proposed a dynamic resource allocation technique that is called Experience-Based Dynamic Soft Frequency Reuse (EBDSFR). We compared our proposed scheme with different resource allocation schemes that are Dynamic Inter-cellular Bandwidth Fair Sharing FFR (FFRDIBFS) and Dynamic Inter-cellular Bandwidth Fair Sharing Reuse-3 (Reuse3DIBFS). Simulation results indicate that, proposed EBDSFR benefits from overall cell throughput and obtains higher user fairness than the reference schemes.

5

Outage Performance of Bidirectional Full-Duplex Amplify-and-Forward Relay Network with Transmit Antenna Selection and Maximal Ratio Combining

Rajesh R., Velmurugan P. G. S., Thiruvengadam S. J., Mallick P. S.

Journal of Telecommunications and Information Technology

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2018

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nr 1

62--69

EN

In this paper, a bidirectional full-duplex amplify- and-forward (AF) relay network with multiple antennas at source nodes is proposed. Assuming that the channel state information is known at the source nodes, transmit antenna selection and maximal ratio combining (MRC) are employed when source nodes transmit information to the relay node and receive information from the relay node respectively, in order to improve the overall signal-to-interference plus noise ratio (SINR). Analytical expressions are derived for tight upper bound SINR at the relay node and source nodes upon reception. Further, losed form expressions are also derived for end-to-end outage probability of the proposed bidirectional full-duplex AF relay network in the Nakagami-m fading channel environment. Although self-interference at the relay node limits the performance of the full-duplex network, the outage performance of the proposed network is better than that of conventional bidirectional full-duplex and half-duplex AF relay networks, due to the selection diversity gain in TAS and diversity and array gain in MRC.

6

Cooperation of wireless networks IEEE 802.15.4 and IEEE 802.11b/g – introduction and measurements

Krupanek B., Bogacz R.

Przegląd Elektrotechniczny

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2016

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R. 92, nr 11

132--135

EN

Article shows a description of influence of transmission in IEEE 802.11b/g standard (commonly called Wi-Fi) on transmission in IEEE 802.15.4 standard identified with ZigBee specification. The measurement verification of influence of Wi-Fi on ZigBee is presented. This type of measurement can be useful in WSNs because they are often collocated near to wireless computer networks which may cause disturbances in data transmission.

PL

Artykuł przedstawia wpływ transmisji prowadzonej w standardzie IEEE 802.11b/g (popularnie nazywanym Wi-FI) na transmisję w standardzie IEEE 802.15.4 utożsamianym z ZigBee. W artykule przedstawiono pomiary różnych parametrów sieci pokazujące wpływ Wi-Fi na ZigBee. Tego typu pomiary mogą być przydatne w sieciach pomiarowych, które narażone są na zaburzenia pochodzące od obecnych prawie wszędzie bezprzewodowych sieci komputerowychArtykuł przedstawia wpływ transmisji prowadzonej w standardzie IEEE 802.11b/g (popularnie nazywanym Wi-FI) na transmisję w standardzie IEEE 802.15.4 utożsamianym z ZigBee. W artykule przedstawiono pomiary różnych parametrów sieci pokazujące wpływ Wi-Fi na ZigBee. Tego typu pomiary mogą być przydatne w sieciach pomiarowych, które narażone są na zaburzenia pochodzące od obecnych prawie wszędzie bezprzewodowych sieci komputerowych.

7

Link Quality and Energy Aware Geographical Routing in MANETs using Fuzzy Logics

Mishra P., Gandhi C., Singh B.

Journal of Telecommunications and Information Technology

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2016

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nr 3

5--17

EN

In literature, varieties of topology and geographical routing protocols have been proposed for routing in the MANETs. It is widely accepted that the geographical routings are a superior decision than topological routings. Majority of geographical routing protocols assume an ideal network model and choose the route that contains minimum number of hops. However, in reality, nodes have limited battery power and wireless links are additionally unreliable, so they may highly affect the routing procedure. Thus, for reliable data transmission, condition of the network such as link quality and residual energy must be considered. This paper aims to propose a novel multi-metric geographical routing protocol that considers both links-quality and energy metric along with progress metric to choose the next optimal node. The progress is determined by utilizing greedy as well as compass routing rather than pure greedy routing schemes. To combine these metrics, fuzzy logics are used to get the optimal result. Further, the protocol deals with “hole” problem and proposes a technique to overcome it. Simulations show that the proposed scheme performs better in terms of the packet delivery ratio, throughput and residual energy than other existing protocols.