• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.180-185
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• 2000

In this paper, we designed 2303.15MHz Sequency synthesizer for the purpose of the phase noise prediction. For the modeling of phase noise Oersted in the designed system through inooducing the noise-modeling method suggested by Lascari we analyzied a variation of phase noise as according as that of offest frequency. Especially, for the third-order system of the PLL among some kinds of phase noise generated from VCO we analyzed the aspect of 1/f-noise appearing troubles in the low frequency band. Since it is difficult to analyze mathematically 1/f-noise in the third-order system of the PLL, introducing the concept of pseudo-damping factor has made an ease of the access of the 1/f-noise variance. we showed a numerical formula of 1/f-noise variance in the third-order system of the PLL which is compared with that of 1/f-noise variance in the second-order system of the PLL

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.8
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• pp.1780-1786
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• 2005

The phase error generated in the transmission system affects the performance of digital transmission signal. The phase error are generated by random phase noise and tracking phase error due to denier phenomenon. In the mobile satellite communication system that generates the doppler frequency, which is a system with a movement, the proper system phase noise spectrum should be designed based on analyses for phase noise and static phase error effects. Based on the analyses of the doppler frequency and the phase error for bilateral satellite communication system providing an asynchronous service, the phase noise spectrums for the mobile satellite communication are designed in this paper. Also, the available transmission services under the less doppler effect are proposed and the proper signal source units for a required transmission system can be designed under the proposed system phase noise spectrum.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.7
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• pp.1247-1253
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• 2007

The system phase noise spectrum distribution for COMS sensor data transmitter and receiver system was proposed in this paper. On the basis of the analyzed design parameter to reduce the phase noise effect in a receiver, the optimal system phase noise were proposed for raw, IRIT and HRIT data transmission that are sensor data, respectively. The proposed system phase noise provides the qualified transmission performance of sensor data and reduces the performance degradation due to phase noise generating in the transmission channel. Also the system phase noise spectrums are utilized in the design of frequency generation source for sensor data transmission and receiver system.

• Current Optics and Photonics
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• v.2 no.5
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• pp.395-399
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• 2018

This article investigates the mechanism of electronic signal phase noise degradation induced by laser phase noise in optical links comprising optical resonators. Through theoretical derivation, we find that the phase noise of the output electronic signal has the same spectral shape of optical intensity noise as the output of the optical resonator. We propose that the optical resonator transfers laser phase noise to light intensity fluctuation and then the intensity fluctuation is converted to electric phase noise through AM-PM conversion mechanism in the photodiode. An optical link comprising a Fabry-Perot resonator was constructed to verify the proposed mechanism. The experimental results agree with our theoretical prediction verifying that the supposition is correct.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.4
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• pp.481-488
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• 2011

In this paper, we study a novel wireless interference cancellation system(ICS) repeater based on OFDM system with phase noise analysis and performance evaluation. Recently, there were many researches about wireless repeater. The previous study is just considering the feedback channel cancellation algorithm. But, in wireless repeater system, the phase noise effect can exist at up and down converter of wireless repeater. In wireless repeater system, if there are phase noise effects, the performance of system will get worse. So, the phase noise compensator is needed in wireless repeater. Therefore, we propose adaptive phase noise compensator based on OFDM system in order to effectively cancel phase noise. In order to cancel interference, we adapt adaptive phase noise compensator in wireless repeater system. The adaptive phase noise compensator compensates phase noise effect. Therefore, in this paper, we analyze phase noise of wireless repeater based on OFDM system. In this paper, when phase noise power is -15 dBc and phase noise cutoff frequency is 100 kHz at 4QAM, the BER performance of propose algorithm is better about 4 dB than with adaptive equalizer and without phase noise compensator at $10^{-4}$.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.5
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• pp.818-824
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• 2011

In this paper, we proposed a phase noise model of a frequency synthesizer for a radar system. Especially, it was proposed a phase noise model in a DAS(Direct Analog Synthesizer) and a frequency up converter system using Leeson's model. The proposed phase noise model was derived from the measurement data of model 1 and evaluated by adapting to model 2 and model 3 frequency synthesizers. The prediction phase noise by modeling was totally matched to the measured data and the effective analysis of the phase noise was done in a frequency synthesizer and a frequency converter of radar system.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.233-236
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• 2005

Phase noise in a phase-locked-loop (PLL) is unwanted and unavoidable. It is a main concern in oscillation system especially PLL. The phase noise is derived in term of power spectrum density by using a reliable phase noise model. There are four noise sources being considered in this paper, which are generated by reference oscillator, voltage controlled oscillator, filter, and main divider. The major concern for this paper is the noise from the filter. Two types of second order low pass filter are used in the PLL system. Applying the mathematical phase noise model, the output noises are compared. The total noise from the passive filter is lower than the active filter at the offset frequency range between 1 Hz to 33 kHz.

• International Journal of Ocean System Engineering
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• v.1 no.4
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• pp.205-210
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• 2011

High data-rate underwater communications is demanded. This demand imposes stringent requirements on underwater communication equipment of phase-locked-loop (PLL). Phase noise in PLL is unwanted and unavoidable. In this paper, we investigate the PLL phase noise effect on high order QAM for underwater communication systems. The phase noise model using power spectral density is adopted for performance evaluation. The phase noise components considered in PLL are reference oscillator, voltage controlled oscillator (VCO), filter and divider. The filters in PLL noise are assumed to be second order active and passive low pass filters. Through simulation, we analyze the phase noise characteristics of the four components and then investigate the performance improvement factor of each component. Consequently, we derive specifications of VCO, phase detector, divider to meet performance requirement of high data-rate communication using QAM under phase noise influence.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.735-738
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• 2005

The phase error in the digital transmission system are generated by random phase noise and tracking phase error due to doppler phenomenon. In the mobile satellite communication system that generates the doppler frequency, which is a system with a movement, the proper system phase noise spectrum should be designed based on analyses for phase noise and static phase error effects. Based on the analyses of the doppler frequency and the phase error for bilateral satellite communication system providing an asynchronous service, the phase noise spectrums for the mobile satellite communication are designed in this paper. Also, the available transmission services under the less doppler effect are proposed and the proper signal source units for a required transmission system can be designed under the proposed system phase noise spectrum.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.243-249
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• 2006

In this paper, the phase noise effects of OFDM transmission diversity systems were analyzed. Since OFDM communication system is very sensitive to phase noise, the system performance may degrade seriously due to the increase of subcarrier interferences and system noise. Therefore, The phase noise model was suggested and its distribution and power were varied to investigate the effects of phase noise on the system performance. The degree of the system performance degradation depends on the specific diversity structures of transmission systems. Here, the performances of OFDM systems with two and three antennas transmission diversity were analyzed and compared with that of systems without transmission diversity as the phase noise characteristics varied.