Correction to: Modern Digital Radio Communication Signals and Systems

2019 ◽  
pp. C1-C11
Author(s):  
Sung-Moon Michael Yang
Keyword(s):  
Radio Communication ◽  
Digital Radio ◽  
Communication Signals

scholarly journals Performance of Base Stations in Railway Digital Radio Communication Networks

2021 ◽  
Vol 19 (2) ◽  
pp. 41-48
Author(s):  
Yu. V. Nemtsov ◽  
I. V. Seryogin ◽  
P. I. Volnov
Keyword(s):  
Communication Network ◽  
Communication Networks ◽  
Base Station ◽  
Base Stations ◽  
Radio Communication ◽  
Radio Communications ◽  
Digital Radio ◽  
Cargo Transportation ◽  
Assess Quality

Base station (BS) is a terminal device of a radio communication network, while railway radio communications play an important role in ensuring safety of passenger and cargo transportation.A proposed method for calculating the performance of base stations in railway digital radio communication networks is intended to calculate for the BS the probabilities of being in certain state.BS was decomposed and such functional elements as circuit groups and a radio frequency path were identified, as well as the central module ensuring the exchange of information with elements of this BS and with other BSs. A detailed study of each element has increased accuracy of the proposed method. Following the Markov model, BS is presented as a system in which all possible states are considered. Models for BS with two and three circuit groups have been constructed. The parameters of each functional element of the model can be obtained through observation over a certain period. The solution of the system of equations for each of the models presented in the article will allow obtaining the values of the system being in a certain state. The obtained characteristics can be used to calculate the reliability of the entire radio communication network, and then to assess quality of service provided to the users of this network.Conclusions are made about the possibilities of using the obtained models when designing new railway communication networks and when calculating quality indices of existing ones. The proposed models can be applied not only to railway radio communication networks but also to mobile communication networks of commercial operators. 

scholarly journals Centrally Reserved Access Model to the Medium in Digital Radio Communication Networks

2020 ◽  
Vol 19 (6) ◽  
pp. 1332-1356
Author(s):  
Maksim Peregudov ◽  
Anatoliy Steshkovoy
Keyword(s):  
Ieee 802.11 ◽  
Communication Networks ◽  
Data Transmission ◽  
Multiple Access ◽  
Model Development ◽  
Transmission Channel ◽  
Radio Communication ◽  
Digital Radio ◽  
Relationship Of ◽  
Sequential Relationship

Currently, centrally reserved access to the medium in the digital radio communication networks of the IEEE 802.11 family standards is an alternative to random multiple access to the environment such as CSMA/CA and is mainly used in the transmission voice and video messages in real time. Centrally reserved access to the environment determines the scope of interest in it from attackers. However, the assessment of effectiveness of centrally reserved access to the environment under the conditions of potentially possible destructive impacts was not carried out and therefore it is impossible to assess the contribution of such impacts to the decrease in the effectiveness of such access. Also, the stage establishing of centrally reserved access to the environment was not previously taken into account. Analytical model development of centrally reserved access to the environment under the conditions of destructive influences in digital radio communication networks of the IEEE 802.11 family standards. A mathematical model of centrally reserved access to the environment has been developed, taking into account not only the stage of its functioning, but also the stage of formation under the conditions of destructive influences by the attacker. Moreover, in the model the stage of establishing centrally reserved access to the medium displays a sequential relationship of such access, synchronization elements in digital radio communication networks and random multiple access to the medium of the CSMA/CA type. It was established that collisions in the data transmission channel caused by destructive influences can eliminate centrally reserved access to the medium even at the stage of its establishment. The model is applicable in the design of digital radio communication networks of the IEEE 802.11 family of standards, the optimization of such networks of the operation, and the detection of potential destructive effects by an attacker.

scholarly journals Frequency-Selective Wallpaper for Indoor Interference Reduction and MIMO Capacity Improvement

Symmetry ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 695
Author(s):  
José-Víctor Rodríguez ◽  
Mats Gustafsson ◽  
José-María Molina-García-Pardo ◽  
Leandro Juan-Llácer ◽  
Ignacio Rodríguez-Rodríguez
Keyword(s):  
Mimo Systems ◽  
Radio Channel ◽  
Multiple Input Multiple Output ◽  
Singular Values ◽  
Indoor Environments ◽  
Radio Communication ◽  
Single Input Single Output ◽  
Communication Signals ◽  
Frequency Selective ◽  
5 Ghz

This paper presents the design and features of frequency-selective wallpaper—based on periodic and symmetric metallic hexagons—intended to be attached to standard walls for filtering out 5 GHz signals (e.g., IEEE 802.11a systems) without blocking other selected radio communication services (e.g., cellular mobile communication signals). It analyzes the characteristics of the radio channel—as found within standard indoor environments—with both regular walls and walls with the proposed frequency-selective wallpaper, examined using a ray-launching program for single-input single-output (SISO) and multiple-input multiple-output (MIMO) systems. This allows the harvesting of parameters, including channel capacity, power delay profile, and signal-to-interference ratio, for proper comparison between the two environments under study: with and without the presented wallpaper. The achieved results clearly show that the use of the proposed frequency-selective wallpaper in an indoor scenario reduces interference levels by an additional attenuation of up to 20 dB in comparison to an unpapered wall. Additionally, with MIMO systems, radio channel characteristics, such as capacity, are improved due to the increase in the magnitude of all singular values of the channel transfer matrix compared to the unpapered wall case, thereby leading to the existence of more relevant subchannels.

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