• 한국광학회지
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• 제13권4호
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• pp.295-300
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• 2002

20 Gb/s 광 전송 시스템을 위한 광 송신기와 수신기를 전기적 시분할 다중 방식으로 제작하고 그 특성을 측정하였다. 특히 광 수신기의 핵심 회로인 클럭(19.906㎓) 추출 회로의 구현을 위해 반파장 지연 선로와 상용화된 EX-OR 소자를 이용한 NRZ-PRZ 변환기와 유전체 공진기를 이용한 협대역 대역통과 필터 및 마이크로스트립 대역통과 필터를 설계, 제작하였으며, 최종적으로 수신부에서 1:2로 역다중화된 10 Gb/s 신호의 비트 오율(BER)을 측정하였다. 제작된 송ㆍ수신기를 직접 연동하였을 때, 수신기의 수신 감도는 BER $1{\times}10^{-12}$에서 -26.2dBm을 나타내었다.

• 대한전자공학회논문지SD
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• 제43권7호
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• pp.13-19
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• 2006

5Gb/s대역 크로스커플 구조의 트랜스임피던스 증폭기 및 제한증폭기가 연결된 광 수신기를 광 PCB에 응용하기 위해 설계 하였다. 회로는 0.18um CMOS 공정으로 구현되었다. 광 수신기는 0.5pF 광 다이오드 기생 캐퍼시턴스에서 $92.8db{\Omega}$ 임피던스 이득과 5Gbps의 주파수 대역을 갖는다. 그리고 1.8V, 2.4V 공급전압에서 9.74mV의 전력소모를 보인다. 입력단의 임피던스는 $50{\Omega}$ 이다. 회로를 광 PCB기판에 올려 광신호 송신 실험하여 5Gb/s 데이터의 수신을 확인하였다.

• 대한전자공학회논문지SD
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• 제47권8호
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• pp.13-22
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• 2010

Independent-Gate-Mode Double-Gate(IGM-DG) MOSFET은 기존의 bulk-MOSFET에 비해 향상된 채널 제어능력을 가지며, front-게이트와 back-게이트를 서로 다른 전압으로 구동가능하다는 이점을 가진다. 따라서, 이를 이용한 회로설계는 4-terminal의 자유도를 이용함으로써 회로성능의 향상 뿐 아니라 집적도 향상을 기대할 수 있다. 본 논문에서는 IGM-DG MOSFET의 장점을 이용하여 TIA, feedforward LA, 및 OB로 구성된 15Gb/s 광수신기를 설계하고, HSPICE 시뮬레이션을 통한 회로성능 검증 및 외부환경과 소자의 특성변화에 따른 안정성을 검증하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.154-157
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• 2004

With the need of high-speed and mass data transmission, optical communication system requires the growth of optical components. Waveguide photodiodes(WGPDs) are introduced and circuit models of WGPD and submodule are required for the optical receiver application. In this paper, the circuit models of WGPD and submodule are investigated and modeling results are derived by PEEC methodology. The s-parameters are measured for the test structures of WGPD and submodule and the equivalent circuit models are examined. The modeling results agreed well with the measured data and can present a reasonable physical representation.

• 대한전자공학회논문지
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• 제25권3호
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• pp.238-242
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• 1988

It is analyzed how performance of phase-locked loop driven by photodetector current in optical receiver will be changed under the condition that Gaussian thermal noise, pattern noise and shot noise are present and the loop has the nonzero detuning frequency. The phase error variance cahnges with the circuit configuration and the produced noise models. The analyzed results are applied to the previously implemented 90.194Mbps optic system whose loop filter is the improved active noninverting 1-st order lag-lead type.

• Journal of the Optical Society of Korea
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• 제19권4호
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• pp.334-339
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• 2015

Terabit-per-second (Tb/s) transmission capacity for the next generation of long-haul communication networks can be achieved using multicarrier optical super-channel technology. In an elastic orthogonal frequency division multiplexing (OFDM) super-channel transmission system, demultiplexing a portion of an entire spectrum in the form of a subband with minimum power is critically required. A major obstacle to achieving this goal is the analog-to-digital converter (ADC), which is power-hungry and extremely expensive. Without a proper ADC that can work with low power, it is unrealistic to design a 100G coherent receiver suitable for a commercially deployable optical network. Discrete Fourier transform (DFT) is often seen as a primary technique for understanding partial demultiplexing, which can be attained either optically or electronically. If fairly comparable performance can be achieved with an all-optical DFT circuit, then a solution independent of data rate and modulation format can be obtained. In this paper, we investigate two distinct OFDM super-channel receiver models, based on electronic and all-optical DFT-technologies, for partial carrier demultiplexing in a multi-Tb/s transmission system. The performance comparison of the receivers is discussed in terms of bit-error-rate (BER) performance.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.191-196
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• 2005

A low-cost, high-performance 40 Gb/s clock recovery module using a phase-locked loop(PLL) for a 40 Gb/s optical receiver has been designed and implemented. It consists of a clock recovery circuit, a RF mixer and frequency discriminator for phase/frequency detection, a DR-VCO, a phase shifter, and a hold circuit. The recovered 40 GHz clock is synchronized with a stable 10 GHz DR-VCO. The clock stability and jitter characteristics of the implemented PLL-based clock recovery module has shown to significantly improve the performance of the conventional open-loop type clock recovery module with DR filter. The measured peak-to-peak RMS jitter is about 230 fs. When input signal is dropped, the 40 GHz clock is generated continuously by hold circuit. The implemented clock recovery module can be used as a low-cost and high-performance receiver module for 40 Gb/s commercial optical network.

• 한국광학회:학술대회논문집
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• 한국광학회 1991년도 제6회 파동 및 레이저 학술발표회 Prodeedings of 6th Conference on Waves and Lasers
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• pp.121-125
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• 1991

A basic coherent optical transmission was demonstrated using FSK modulation and heterodyne detection scheme. Optical frequency of DFB LD light source at the transmitter side was stabilized with Fabry Perot etalon and bias feedback circuit. A tunable external cavity LD was used as a local oscillator at the receiver. Heterodyned output signal at IF frequency of 2GHz was measured and discussed.

• ETRI Journal
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• 제28권1호
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• pp.103-106
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• 2006

We have fabricated a planar lightwave circuit (PLC) hybrid-integrated optical sub-assembly of a triplexer using a thin film filter (TFF)-attached wavelength division multiplexer (WDM) and photodiode (PD) carriers. Two types of TFFs were attached to a diced side of a silica-terraced PLC platform, and the PD carriers with a $45^{\circ}$ mirror on which pin-PDs were bonded were assembled with the platform. A clear transmitter eye-pattern and minimum receiver sensitivity of -24.5 dBm were obtained under 1.25 Gb/s operation for digital applications, and a second-order inter-modulation distortion (IMD2) of -70 dBc was achieved for an analog receiver.

• Journal of information and communication convergence engineering
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• 제6권4호
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• pp.439-443
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• 2008

It is shown that even if the modulating frequency of the light is too high for direct detection the signal can be extracted by frequency conversion at the same time as the detection by means of the nonlinearity of the APD. When this frequency conversion detection is applied to an optical receiver, the detection bandwidth can be increased while the configuration of the optical detection circuit and the signal processing in the subsequent stages are simplified. A fundamental analysis is carried out with an APD which is confirmed experimentally.