• ETRI Journal
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• v.34 no.5
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• pp.763-766
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• 2012

This letter proposes an iterative multimode precoding scheme with limited feedback for nonreciprocal MIMO interference channels. Based on analysis of game theory, we model the iterative multimode precoding as a noncooperative game with a finite set of strategies. Numerical results are presented to verify the sum rate performance of the proposed scheme.

• Journal of applied mathematics & informatics
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• v.18 no.1_2
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• pp.431-439
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• 2005

The aim of this paper is to derive the analytical solution of the queue: $M/E_{r}/1/k/N$ for machine interference system with balking and reneging considering the discipline FIFO. Some measures of effectiveness and some special cases are obtained.

• Communications of the Korean Mathematical Society
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• v.16 no.4
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• pp.659-666
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• 2001

The aim of this paper is to derive the analytical so-lution of the queue: H$_{r}$/M/c/k/N for machine interference with balking and reneging, and FIFO (first in, first out) service disci-pline.e.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.2
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• pp.41-45
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• 2019

In this paper, we propose the interference cancellation scheme of end-to-end method algorithm for power line communication (PLC) systems in smart grid. The proposed scheme estimates the channel noise information of receiver by applying a deep learning model at the receiver. Then, the estimated channel noise is updated in database. In the modulator, the channel noise which reduces the power line communication performance is effectively removed through interference cancellation technique. As an impulsive noise model, Middleton Class A interference model was employed. The performance is evaluated in terms of bit error rate (BER). From the simulation results, it is confirmed that the proposed scheme has better BER performance compared to the theoretical model based on additive white Gaussian noise. As a result, the proposed interference cancellation with deep learning improves the signal quality of PLC systems by effectively removing the channel noise. The results of the paper can be applied to PLC for smart grid and general communication systems.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.3
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• pp.167-174
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• 2021

Computational Fluid Dynamics (CFD) was performed under low-speed wind tunnel test conditions using a 29.7% scale model of the NASA common research model. A wind tunnel test was conducted to measure the aerodynamic coefficient of the CRM with Belly sting model support configuration at a low Reynolds number of 0.3×106 and it was compared with the aerodynamic coefficient of CFD analysis. In order to verify the validation of the analysis, a computational analysis under the conditions of the advance research was performed and compared. The interference effect of the Belly sting model support affected not only the fuselage but also the main and tail wings.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.663-668
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• 2008

Recently, World Radio Conference(WRC)-2007 approved the ultrawide bandwidth of 500 MHz for the use of spaceborne synthetic aperture radar in X-band for the EESS(Earth Exploration Satellite Service) in order to improve the SAR imaging resolution. It is concerned about the interference impact from the spaceborne SAR that may cause to most of ground radars due to the extended ultra wideband. In this paper, in order to predict the interference impact of the ground-based radar from the spaceborne radar, radar interference model is presented using radar characteristic parameters by taking into account the operating environments of the spaceborne and ground based radar in the time, space, and spectrum domains. Using the spaceborne SAR model of TerraSAR-X and ground radar model of meteorological radar recommended by ITU-R, the interference impact was assessed through the computer simulation to see the possible interference impact of the ground based radar operating in the Korean peninsula.

• Journal of Advanced Navigation Technology
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• v.26 no.6
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• pp.481-486
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• 2022

The recent rapid growth of the IoT(Internet of Things) is leading to the spread of low-power wireless technology. A major challenge in designing IoT wireless networks is to achieve coexistence between different wireless technologies that share the 2.4 [GHz] ISM (Industrial Scientific Medical) frequency band. Therefore, there is a need for research on improving the reliability of wireless networks and coexisting operation between wireless networks. In particular, it is necessary to study an interference model and performance for mutual service coexistence in a BLE (Bluetooth Low Energy) wireless network environment, which is expected to be widely used as a connection medium between devices in various industrial fields. In this paper, the co-channel interference model with the IEEE 802.15.4 system is established focusing on the physical layer of the BLE system widely used in residential and industrial wireless applications, and the performance of the BLE wireless communication system is analyzed in the co-channel interference environment. As a result of the analysis, as the distance between the interference source and the BLE system increases in an environment where noise and co-channel interference exist, the amount of co-channel interference decreases and the error rate performance of the BLE system improves.

• Wind and Structures
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• v.31 no.5
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• pp.431-443
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• 2020

The modern tall buildings are often constructed as an unconventional plan and as twin buildings. Wind load on the tall building is significantly influenced by the presence of another building in the near vicinity. So, it is imperative to study wind forces on an unconventional plan shaped tall building. Mean wind pressure coefficients of a square and 'H' plan shape tall buildings are investigated using wind tunnel experiments. The experiments were carried out for various wind directions from 00 to 900 at an interval of 300 and various locations of the identical interfering building. The experimental results are presented at the windward face from the viewpoint of effects on cladding design. To quantify the interference effects, interference factors (I.F) are calculated. Mean pressure coefficients of both models are compared for isolated and interference conditions. The results show that pressure reduces with an increase in wind angle till 600 wind direction. The interfering building at full blockage interference condition generates more suction than the other two conditions. The interference factor for both models is less than unity. H-plan building model is subjected to a higher pressure than the square model.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.10
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• pp.25-32
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• 2011

We have analyzed adjacent cell dependency of threshold voltage shift caused by the cell to cell interference, and we proposed a 3-adjacent-cell model to model the pattern dependency of the threshold voltage shift. The proposed algorithm is verified by using MATLAB simulation and measurement results. In the experimental results, we found that accuracy of the proposed simple 3-adjacient-cell model is comparable to the widely used conventional 8-adjacient-cell model. The Bit Error Rate (BER) of LSB and of MSB is improved by 28.9% and 19.8%, respectively, by applying the proposed algorithm based on 3-adjacent-cell model to 20nm-class 2-bit MLC NAND flash memories.

• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.251-254
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• 2003

In this paper, we develop an effective method for estimating and predicting interference power strength using the IMM(Interacting Multiple Model) algorithm. Based on the proposed interference prediction algorithm, we adjust transmission power of mobile terminals to maintain a certain level of target signal - to - interference- plus -noise- ratio ( SINR ) at the base station. Results of numerical experiments are presented to show a performance profile of the proposed algorithm.