• Journal of the Korea Institute of Information and Communication Engineering
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• 제15권11호
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• pp.2307-2312
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• 2011

In this paper, we analyze the interference probability according to distance between mobile stations as a parameter which is be used for analysis for co-existing in co-channel of different systems. In order to consider interfering between each systems, we analyze two cases. First, WiBro is an interfering transmitter and WLAN is a victim receiver. Second, WLAN is an interfering transmitter and WiBro is a victim receiver. When interfering transmitter is WiBro and WLAN, interference probability according to distance between systems is analyzed by setting transmit power of 25 and 23 dBm, respectively. These simulation results can be applied into criteria data for channel co-existing issue in real field.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.553-556
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• 2012

The interference among the rain radars and interference in the adjacent wireless station due to the spurious signals from the rain radar were analyzed in this paper. The rain radar measures the rain intensity using S-band signal. The measured data are utilized in forecasting the rainfall. The interference among the rain radars or in the adjacent wireless stations may be caused by the high output power of rain radar. Based on the propagation analysis of S band signal and the deduced interference protection ratio of rain radar, the interference due to the rain radar are analyzed. Also, the radiation spectrum characteristics of a rain radar are deduced from the caused interference effects by the spurious signals of the rain radar.

• 한국ITS학회:학술대회논문집
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• 한국ITS학회 2008년도 제7회 추계학술대회 및 정기총회
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• pp.548-550
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• 2008

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제17권2호
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• pp.152-157
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• 2006

In this paper, we have analyzed the effects of interference from HAPS ground stations to P-MP FWA base station and to P-MP FWA terminal station using more detail parameters such as a new interference model, a realistic HAPS scenario, practical antenna patterns for both the HAPS system and FWA systems. The analysis results show that, in the case of interference from HAPS GSs into a P-MP BS, compatibility of the two systems can be obtained by using a sectored BS antenna with the boresight directed away from the nadir. However, in the case of interference from HAPS GSs into a P-MP TS, the two systems cannot operate effectively in the same band unless the separation distance is guranteed and/or some form of interference mitigation technique is employed such as dynamic channel allocation.

• Journal of Satellite, Information and Communications
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• 제11권1호
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• pp.6-11
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• 2016

In this paper, we have analyzed the effects of co-channel, adjacent-channel, and the human shield(Body Blockage) for wideband WLAN based on the IEEE802.11n 40MHz channel bandwidth required for high speed digital signage service. Simulation results show that wideband WLAN can be operated with 78 interferers over 63m distance in co- channel, 80 interferer over 61m distance in adjacent channel. By applying the mitigation method for reducing the interference, we have confirmed that protection distance is improved to 51m using beamforming, and 40m using cognitive radio in co-channel interference. Also body blockage interference is reduced using adaptive channel bandwidth, C/I ratio, beamforming, power control mitigation methodology.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제34권6A호
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• pp.468-475
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• 2009

In OFDM-based Full Duplex Relays (FDR) with Decode and Forward (DF) scheme, an interference cancellation technique in the frequency domain is more efficient than the one in the time domain. However, an Inter-Symbol Interference (ISI) and Inter-Carrier Interference (ICI) may occur due to the timing mismatch between the feedback interference signal and the desired signal from Base Station (BS) when the feedback interference cancellation and demodulation are performed in the frequency domain. In this paper, the effects of timing mismatch on the synchronous type and asynchronous type of OFDM-based FDR are analyzed for uplink and downlink cases. Then, synchronization procedure and methods for reducing ISI and ICI in OFDM-based FDR with frequency-domain feedback interference canceller are proposed and verified by computer simulation.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 한국전자파학회 2001년도 종합학술발표회 논문집 Vol.11 No.1
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• pp.49-52
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• 2001

본 논문에서는 몬테카를로 기법 및 최소결합손실(MCL : Minimum Coupling Loss)기법을 기반으로 하여 무선통신 서비스간 보호비를 만족시키도록 최적의 보호대역을 자동으로 설정할 수 있는 알고리즘을 개발하고 그 견과를 기술하였다. 여기서 개발된 보호대역 자동 설정 알고리즘은 통계적인 몬테카를로 기법 및 간섭원과 대상 수신기 사이에 간섭이 존재하지 않도록 요구되는 이격도 계산을 위한 최소결합손실기법을 적용하여, 주어진 간섭보호비를 만족할 수 있는 최악의 상황에 대한 보호대역을 먼저 설정한 후 보호대역값을 변화시키면서 희망 수신기에서의 간섭확률을 계산을 통해 최적의 보호대역을 설정할 수 있다. 이 기법은 어떠한 형태의 무선통신 서비스에 대해서도 동시에 두가지의 간섭원이 영향이 미칠 경우에도 적용할 수 있도록 설계되었다. 또한 본 연구에서는 TDD시스템간의 간섭 시나리오를 설정하고, 개발된 보호대역 자동 선정 알고리즘을 사용한 시뮬레이터와 ITU-R에서 개발된 SEAMCAT에 의해 얻어진 보호대역 도출 결과를 비교, 분석함으로써 개발된 알고리즘의 신뢰성을 검증하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제28권1A호
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• pp.34-40
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• 2003

Because that the wireless LAN and the Bluetooth which are currently used are operating at the ISM 2.4GHz, we must meet the frequency interference So performance degradation is occurred by frequency interference between the wireless LAN and the Bluetooth In this paper, for decreasing the errors between the communication systems because of the interferences, we analysis the influence of mutual interference between the local communication systems and the specification of frequency interference problem on the Bluetooth, the wireless LAN and home electronic products

• Journal of the Korean Society of Propulsion Engineers
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• 제3권3호
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• pp.9-15
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• 1999

The Analysis of spray characteristics for combined spray group are necessary to develop large rocket engine. In this study, basic effects of interaction from spray fan formed by impinging jets were investigated with respect to mass distribution, droplet velocities and diameter. Patternater and PDPA are used for experimental apparatus. Water was used as a test fluid When momentum ratio is 1, effect of interaction from collision of spray fan on mass distribution are small. Also, effect of interaction from collision of spray fan on droplet velocities and diameter are small. But, droplet diameter is smaller near collision point due to second collision. Therefor, for the same momentum ratio from spray fan formed by impinging jets, we may neglect effect of interaction on mass distribution, droplet velocities and diameter.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제39C권1호
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• pp.36-44
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• 2014

Broad band and wide area satellite communication has advantage that can be always communicate with anyone regardless of time and space. In the other hands, its communication quality is easy to be affected by interference signals. Due to the fact that interference signal can be transmitted from everywhere, it's hard to find the illegal source of signal and it has huge influence. In this paper, with this influence of interference signal, we introduce the interference rejection method, implementation and test result in the digital satellite communication processing the signal using variety of digital method. It will be useful information to improve the interference rejection function and also be helpful on the field of satellite communication.