• Journal of the Korea Society of Computer and Information
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• v.12 no.6
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• pp.243-249
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• 2007

I propose the excess noise suppressed optical sensor network using optical CDMA with gain saturated optical amplifier in order to increase number of sensors simultaneously connected to network. Simulation analyses confirm that the maximum number of sensors simultaneously connected to the optical sensor network can be largely increased by increasing the gain of gain saturated optical amplifier owing to the pression of access noises with the assignment of sweeping frequency of optical sensors within 10MHz. In the case of the requested SNR of 20dB and the sweeping frequency of 10MHz, the maximum number of sensors simultaneously connected to the optical sensor network can be increased four times as many as the conventional system.

• The KIPS Transactions:PartC
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• v.13C no.2 s.105
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• pp.161-166
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• 2006

In this paper, we propose optical subscriber access network to eliminate multiple access interference using 2 dimensional(D) optical frequency and time domain CDMA method. We have numerically analyzed the characteristics of proposed system. It is seen that the excess intensity noise is the major limiting factor to the system. Also it is seen that the number of simultaneous subscribers is four times as large as the conventional ID optical system under the same bit error ratio.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.88-89
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• 2000

광전송 시스템의 전송용량은 WDM 기술의 비약적 성장에 의해 테라 bps급으로 증대된 데 비해 LAN 또는 MAN 등을 포함한 광 다중 접속 네트워크에 대한 연구는 비교적 덜 성숙한 실정이다. 광 코드분할 다중접속 (CDMA) 네트워크는 비동기 다중 사용자 시스템에의 응용 가능성과 자체적인 보안성의 제공으로 광 다중 접속 네트워크 구성의 유망한 해결책 중 하나로 관심을 모으고 있다. 현재까지 다양한 광 CDMA 네트워크 구성 방안들이 제안되었으며 이들은 크게 시간영역 또는 주파수영역에서의 부/복호 방식, 인코히어런트 또는 코히어런트 광 신호처리 방식으로 분류되어진다$^{(1)}$ . (중략)

• The KIPS Transactions:PartC
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• v.11C no.5
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• pp.671-676
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• 2004

In this paper, we propose ultra-fast multimedia optical subscriber access network using optical frequency domain CDMA method in order to access the multimedia with multiple data rates. We numerically analyze the effects of spectral power distortion in the light source for the optical CDMA system modified PN codes and FBG(Fiber Bragg Grating)s. In the proposed multiple-rate multimedia access optical networks, the performances such as BER(Bit Error Rate) are the same for all data regardless of data rates in the case of the same number of simultaneous ONU. In the proposed ultra-fast multimedia optical subscriber access network, the performances for all data are much more improved than those in the conventional system.

• Proceedings of the Optical Society of Korea Conference
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• 2005.07a
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• pp.210-211
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• 2005

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.5 s.347
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• pp.17-24
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• 2006

The optical feedforward is known as a complicated technique in spite of its superior linearization. Here we optimized the feedforward circuit parameters using a systematic approach for optimum efficiency. A systematic approach was verified by transmission experiments of 2.14 GHz two tones. The compared third order IMD was enhanced by 38 dB for two-tone case. The experimental results for transmission of W-CDMA signals were described. The ACPR was enhanced by 20 dB for 1 W-CDMA carrier and by 16 dB for 3 W-CDMA carriers. Also, noise level was reduced by 7 dB.