On the Impact of Uplink Interference Coordination When Using Multiple Antennas at the Base Station

2008 ◽  
Author(s):  
Gabor Fodor ◽  
Chrysostomos Koutsimanis
Keyword(s):  
Multiple Antennas ◽  
Base Station ◽  
Interference Coordination ◽  
The Impact ◽  
Uplink Interference

scholarly journals A PHY Layer Security Analysis of Uplink Cooperative Jamming-Based Underlay CRNs with Multi-Eavesdroppers

2019 ◽  
Author(s):  
Mounia Bouabdellah ◽  
Faissal El Bouanani ◽  
Mohamed-Slim Alouini
Keyword(s):  
Fading Channels ◽  
Multiple Antennas ◽  
Security Analysis ◽  
Base Station ◽  
Artificial Noise ◽  
Cooperative Jamming ◽  
Maximum Ratio Combining ◽  
Single Antenna ◽  
Asymptotic Expressions ◽  
The Impact

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 9.0px Helvetica} span.s1 {font: 7.5px Helvetica} <p>xAbstract—In this paper, the physical layer security of a dualhop</p> <p>underlay uplink cognitive radio network is investigated over</p> <p>Nakagami-m fading channels. Specifically, multiple secondary</p> <p>sources are taking turns in accessing the licensed</p> <p>spectrum of the primary users and communicating with a multiantenna</p> <p>secondary base station (D) through the aid of a multiantenna</p> <p>relay R in the presence of M eavesdroppers </p> <p>that are also equipped with multiple antennas. Among the</p> <p>remaining nodes, one jammer is randomly selected to transmit</p> <p>an artificial noise to disrupt all the eavesdroppers that are</p> <p>attempting to intercept the communication of the legitimate links</p> <p>i.e., Si -R and R-D. The received signals at each node are combined</p> <p>using maximum-ratio combining. Secrecy analysis is provided by</p> <p>deriving closed-form and asymptotic expressions for the secrecy</p> <p>outage probability. The impact of several key parameters on the</p> <p>system’s secrecy e.g., transmit power of the sources, number of</p> <p>eavesdroppers, maximum tolerated interference power, and the</p> <p>number of diversity branches is investigated. Importantly, by</p> <p>considering two scenarios, namely (i) absence and (ii) presence</p> <p>of a friendly jammer, new insights are obtained for the considered</p> <p>communication system. Especially, we tend to answer to the</p> <p>following question: Can better secrecy be achieved without</p> <p>jamming by considering a single antenna at eavesdroppers</p> <p>and multiple-ones at the legitimate users (i.e., relay and enduser)</p> <p>rather than sending permanently an artificial noise and</p> <p>considering that both the relay and the destination are equipped</p> <p>with a single antenna, while multiple antennas are used by the</p> <p>eavesdroppers? The obtained results are corroborated through</p> <p>Monte Carlo simulation and show that the system’s security can</p> <p>be enhanced by adjusting the aforementioned parameters.</p>

scholarly journals A new look on performance of small-cell network with design of multiple antennas and full-duplex

2021 ◽  
Vol 10 (4) ◽  
pp. 2302-2309
Author(s):  
Chi-Bao Le ◽  
Dinh-Thuan Do
Keyword(s):  
Outage Probability ◽  
Multiple Antennas ◽  
Base Station ◽  
Small Cell ◽  
Full Duplex ◽  
Closed Form Expression ◽  
Outage Performance ◽  
Cell Network ◽  
Small Cell Network ◽  
The Impact

A downlink of small-cell network is studied in this paper studies in term of outage performance. We benefit by design of multiple antennas at the base station and fullduplex transmission mode. The scenario of multiple surrounded small-cell networks is considered to look the impact of interference. We derive the closed-form expression of outage probability to show performance of mobile user. We investigate target rate is main factor affecting to outage performance. According to the considered system, simulation results indicate reasonable value of outage probability and throughput as well. Finally, Monte-Carlo simulation method is deployed to determine exactness of main results found in this article. Finally, the considered system can exhibit improved performance if controlling interference term.

scholarly journals A PHY Layer Security Analysis of Uplink Cooperative Jamming-Based Underlay CRNs with Multi-Eavesdroppers

2019 ◽  
Author(s):  
Mounia Bouabdellah ◽  
Faissal El Bouanani ◽  
Mohamed-Slim Alouini
Keyword(s):  
Fading Channels ◽  
Multiple Antennas ◽  
Security Analysis ◽  
Base Station ◽  
Artificial Noise ◽  
Cooperative Jamming ◽  
Maximum Ratio Combining ◽  
Single Antenna ◽  
Asymptotic Expressions ◽  
The Impact

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 9.0px Helvetica} span.s1 {font: 7.5px Helvetica} <p>xAbstract—In this paper, the physical layer security of a dualhop</p> <p>underlay uplink cognitive radio network is investigated over</p> <p>Nakagami-m fading channels. Specifically, multiple secondary</p> <p>sources are taking turns in accessing the licensed</p> <p>spectrum of the primary users and communicating with a multiantenna</p> <p>secondary base station (D) through the aid of a multiantenna</p> <p>relay R in the presence of M eavesdroppers </p> <p>that are also equipped with multiple antennas. Among the</p> <p>remaining nodes, one jammer is randomly selected to transmit</p> <p>an artificial noise to disrupt all the eavesdroppers that are</p> <p>attempting to intercept the communication of the legitimate links</p> <p>i.e., Si -R and R-D. The received signals at each node are combined</p> <p>using maximum-ratio combining. Secrecy analysis is provided by</p> <p>deriving closed-form and asymptotic expressions for the secrecy</p> <p>outage probability. The impact of several key parameters on the</p> <p>system’s secrecy e.g., transmit power of the sources, number of</p> <p>eavesdroppers, maximum tolerated interference power, and the</p> <p>number of diversity branches is investigated. Importantly, by</p> <p>considering two scenarios, namely (i) absence and (ii) presence</p> <p>of a friendly jammer, new insights are obtained for the considered</p> <p>communication system. Especially, we tend to answer to the</p> <p>following question: Can better secrecy be achieved without</p> <p>jamming by considering a single antenna at eavesdroppers</p> <p>and multiple-ones at the legitimate users (i.e., relay and enduser)</p> <p>rather than sending permanently an artificial noise and</p> <p>considering that both the relay and the destination are equipped</p> <p>with a single antenna, while multiple antennas are used by the</p> <p>eavesdroppers? The obtained results are corroborated through</p> <p>Monte Carlo simulation and show that the system’s security can</p> <p>be enhanced by adjusting the aforementioned parameters.</p>

scholarly journals Energy-Efficient Packet Forwarding Scheme Based on Fuzzy Decision-Making in Underwater Sensor Networks

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4368
Author(s):  
Jitander Kumar Pabani ◽  
Miguel-Ángel Luque-Nieto ◽  
Waheeduddin Hyder ◽  
Pablo Otero
Keyword(s):  
Energy Consumption ◽  
Sensor Networks ◽  
Energy Efficient ◽  
Real Life ◽  
Base Station ◽  
Fuzzy Decision Making ◽  
Underwater Sensor Networks ◽  
Packet Forwarding ◽  
Node Number ◽  
The Impact

Underwater Wireless Sensor Networks (UWSNs) are subjected to a multitude of real-life challenges. Maintaining adequate power consumption is one of the critical ones, for obvious reasons. This includes proper energy consumption due to nodes close to and far from the sink node (gateway), which affect the overall energy efficiency of the system. These wireless sensors gather and route the data to the onshore base station through the gateway at the sea surface. However, finding an optimum and efficient path from the source node to the gateway is a challenging task. The common reasons for the loss of energy in existing routing protocols for underwater are (1) a node shut down due to battery drainage, (2) packet loss or packet collision which causes re-transmission and hence affects the performance of the system, and (3) inappropriate selection of sensor node for forwarding data. To address these issues, an energy efficient packet forwarding scheme using fuzzy logic is proposed in this work. The proposed protocol uses three metrics: number of hops to reach the gateway node, number of neighbors (in the transmission range of a node) and the distance (or its equivalent received signal strength indicator, RSSI) in a 3D UWSN architecture. In addition, the performance of the system is also tested with adaptive and non-adaptive transmission ranges and scalable number of nodes to see the impact on energy consumption and number of hops. Simulation results show that the proposed protocol performs better than other existing techniques or in terms of parameters used in this scheme.

The Effect of Hospital Resource Unavailability and Ambulance Diversions on the EMS System

1994 ◽  
Vol 9 (3) ◽  
pp. 172-176 ◽  
Author(s):  
Keith W. Neely ◽  
Robert L. Norton ◽  
Gary P. Young
Keyword(s):  
Prospective Observational Study ◽  
Trauma System ◽  
Base Station ◽  
Computed Tomography Scan ◽  
Hospital Resource ◽  
Multilinear Regression ◽  
Number Of Patients ◽  
The Impact ◽  
Tomography Scan ◽  
Intended Destination

AbstractHypotheses:1) There is no increase in transport or scene time of diverted patients and no increase in distances traveled; 2) hospital resource shortages bear no relationship to the number of patients diverted; and 3) paramedics are able to match their patient correctly with the resources available at a given hospital.Methods:This was a five-month, prospective, observational study in an urban area with a population of 600,000 comparing all 9-1-1 ambulance diversions against a randomly selected sample of 5% of all other 9-1-1 originated patients. All patient diversions that originated from the 9-1-1 center are included in the study.Results:Hospitals identify their diversion status on a community-wide computer system monitored at the 9-1-1 center and base station. Accepted categories include: 1) diversion of all patients through the 9-1-1 center from the emergency department (ED); 2) trauma system patients (T); 3) psychiatric secure beds (PSB); 4) general acute ward beds (AW); 5) critical care (CC); 6) computed tomography scan (CT); 7) labor and delivery (LD); and 8) pediatric beds (PEDS). Data were abstracted from 481 patients' records. A total of 111 were diverted from their intended destination. Transport times were longer and diverted patients traveled further (p <.002). Hospitals showing ED and LD diversion categories were more likely to have patients diverted away (r2 = .895, multilinear regression, p <.001). Of the 111 patients, 21 (19%) were diverted because of CC unavailability. Six of these (28%) were inappropriate because they did not fit the CC definition.Conclusions:In this system, hospital diversions increase transport times and distances traveled. Diversion of patients correlated strongly to unavailability of specific categories. Paramedics make errors in determining appropriate CC diversions. Systems reviewing their diversion problems need to assess the impact of longer out-of-hospital times and of certain diversion categories, and to clarify definitions.

An Efficient IR-HARQ Power Allocation for Relay-Aided Cellular Networks

2018 ◽  
Vol 27 (12) ◽  
pp. 1850195
Author(s):  
P. Mangayarkarasi ◽  
J. Raja
Keyword(s):  
Power Allocation ◽  
Cellular Networks ◽  
Channel Capacity ◽  
Energy Efficient ◽  
Base Station ◽  
Relay Station ◽  
Decode And Forward ◽  
Relay Placement ◽  
Cell Coverage ◽  
The Impact

Energy-efficient and reliable data transmission is a challenging task in wireless relay networks (WRNs). Energy efficiency in cellular networks has received significant attention because of the present need for reduced energy consumption, thereby maintaining the profitability of networks, which in turn makes these networks “greener”. The urban cell topography needs more energy to cover the total area of the cell. The base station does not cover the entire area in a given topography and adding more number of base stations is a cost prohibitive one. Energy-efficient relay placement model which calculates the maximum cell coverage is proposed in this work that covers all sectors and also an energy-efficient incremental redundancy-hybrid automatic repeat request (IR-HARQ) power allocation scheme to improve the reliability of the network by improving the overall network throughput is proposed. An IR-HARQ power allocation method maximizes the average incremental mutual information at each round, and its throughput quickly converges to the ergodic channel capacity as the number of retransmissions increases. Simulation results show that the proposed IR-HARQ power allocation achieves full channel capacity with average transmission delay and maintains good throughput under less power consumption. Also the impact of relaying performance on node distances between relay station and base station as well as between user and relay station and relay height for line of sight conditions are analyzed using full decode and forward (FDF) and partial decode and forward (PDF) relaying schemes. Compared to FDF scheme, PDF scheme provides better performance and allows more freedom in the relay placement for an increase in cell coverage.

METHODS FOR PROTECTING THE EQUIPMENT OF CELLULAR (MOBILE) CONNECTION FROM ELECTROMAGNETIC IMPACT

2021 ◽  
Vol 335 (1) ◽  
pp. 81-89
Author(s):  
Zh. S. Abdimuratov ◽  
Zh. D. Manbetova ◽  
M. N. Imankul ◽  
K. S. Chezhimbayeva ◽  
A. Zh. Sagyndikova
Keyword(s):  
High Frequency ◽  
Electromagnetic Compatibility ◽  
Negative Impact ◽  
High Energy ◽  
Base Station ◽  
Electromagnetic Spectrum ◽  
Negative Consequences ◽  
External Interference ◽  
Extremely High Frequency ◽  
The Impact

Under electromagnetic impact (EMI) of a sufficient level, temporary disruption of functioning, processing, transmission and storage of information in cellular equipment is possible. Possible problems of electromagnetic compatibility (EMC) of a mobile phone and a base station (BS) of cellular connection under the influence of electromagnetic radiation (EMR) from other sources and their negative impact on functioning are considered. The energy of the HF electromagnetic field (EMF) after passing through the protective case can affect the devices of shielded radio electronic equipment (REE), therefore, the possible negative consequences of the impact of high-energy EMF on the REE are described. Possible negative consequences under certain conditions from the influence of the skin-effect, the effects of electrostatic discharge and electromagnetic pulses on electronic devices are given. It is shown that the constructional method of protecting REE from the effects of external electromagnetic factors consists in reducing the collected and transmitted EMF energy by improving the design, placement and installation of equipment. Components of some vendors for 5G systems that are resistant to external interference are given, and the possibilities for reducing the radiation level of a cell phone are noted. The necessity of an integrated approach to solving EMC problems is substantiated, which consists in the use of structural, circuitry and structural-functional methods of EMC provision. The new 5G (Fifth Generation) standard will operate at higher operating frequencies compared to previous generations. Due to the workload of the electromagnetic spectrum at frequencies below 6 GHz, 5G networks will be based on wireless radio access systems operating at frequencies of 30–100 GHz, that is, in the lower band of the extremely high frequency range EHF (Extremely High Frequency), 30–300 GHz.

Optimizing the Traffic of Voice Core Domain in UMTS Network through RNC Re-Homing

2012 ◽  
pp. 227-240
Author(s):  
Ye Ouyang ◽  
Hosein Fallah
Keyword(s):  
Mobile Networks ◽  
Base Station ◽  
Third Generation ◽  
Core Network ◽  
Core Domain ◽  
Network Controller ◽  
Next Generation Mobile Networks ◽  
The Impact ◽  
Umts Networks

The past few years have seen mobile operators transition to next-generation mobile networks, specifically from third-generation networks (3G) to long term evolution (LTE). This paper describes the basic architecture and topology of UMTS R4 core network and introduces two options in network planning, i.e., flat structure or layered structure. This paper introduces the re-homing of radio network controller (RNC) and base station controller (BSC) and studies the impact on the performance of voice core of UMTS networks. The proposed RNC re-homing models are created and analyzed for voice core of UMTS networks. The paper concludes that the appropriate RNC re-homing optimizes the traffic of voice core in UMTS network.

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