• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.11
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• pp.837-842
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• 2017

In this paper, as a basic study for combination of turbo equalizer and 4D-8PSK-TCM(4 Dimensional 8 Phase Shift Keying Trellis Coded Modulation) system, which is recommended for X-band band satellite communication in CCSDS, a system combining 8PSK-TCM system and turbo equalizer has designed and performance evaluation of the system has performed. BER performance of 8PSK and 8PSK-TCM systems has evaluated and analyzed in AWGN, Proakis B and Proakis C channels in detail. As results of simulation, BER performance of 8PSK-TCM system is better than 8PSK system in AWGN environment. Furthermore, it can be confirmed that the system combining the 8PSK-TCM system with the turbo equalizer can further improve the BER performance through iterative equalization in the ISI channel environment. The 8PSK-TCM system combined with the turbo equalizer requires SNR of 5.9 dB for BER performance of $10^{-3}$ with 5 iterative equalization in Proakis B and SNR of 9.1 dB for BER of $10^{-2}$ with 5 iterative equalization in Proakis C.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8A
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• pp.1133-1140
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• 1999

In order to provide high-speed wide-band multimedia services via Low earth(LEO) mobile satellire, power and bandwidth efficient digital transmission technique should to employed. This paper analyzes the performance of Trellis-soded 16QAM and 8PSK-2AM which can transmit twice as much inforemation as QPSK in nonlinearly amplified LEO mobile satellite channel. In the analysis the nonlinear mobile satellite channel is modelled by Rician fading channel amplified by Fujitsu's GaAs FET HPA. Our simulation result shows that 8PSK-2AM is less sensitive to the satellite channel nonlinear distortion and its BER performance is better than that of 16QAM. The BER performance of 8PSK-2AM is further improved by optimizing its signal constellation. Accocordingly it is found that Trellis-coded 8PSK-2AM could provide multimedia services such as Satellite Internet, DBS, DAB and ISDB more efficiently in the power and bandwidth limited mobile satellite channel.

• The Journal of the Acoustical Society of Korea
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• v.9 no.2
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• pp.53-60
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• 1990

MSK waveforms are advantageous from the point of view of reduced interchannel interference. MSK waveform, however, is more difficult to generate than PSK due to its complex pulse shape. A SAW filter is ideally suited for generation of MSK waveform because it provides accurate control of the required impulse responese and linear phase at high frequncies. In this paper, an implementation of SAW based PSK-MSK convert filter, which can easily convert the high frequency PSK waveform to MSK, is studied.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.159-162
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• 1998

본 논문은 단일 채널에 다수의 정보 신호를 전송하기 위하여 사용하는 PCM/PSK/PM 변조 방식의 전송 신호 대역 특성에 대하여 기술하였다. 위성 관제 신호인 원격 명령 신호 및 원격 측정 신호의 변조 지수에 따라 전송에 필요한 대역폭과 위성과의 거리 측정 신호 전송에 필요한 전송 대역폭을 산출하며, 부 반송파 주파수 사용에 대한 관계를 고찰하였다. PCM/PSK/PM 변조 방식의 대역폭은 위상 변조 지수 1.2 rad 이하에서는 부 반송파 주파수와 전송 데이터 율에 비례한다. 2kbps 원격명령 데이터 전소에 필요한 원격 측정 신호를 위한 부 반송파는 131. 072kHz가 적합하다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.1
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• pp.55-62
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• 1983

The error rate performance of phase shift Keyed(PSK) signal has been evaluated in terms of carrier-to-noise ratio(CNR), carrier-to-interferer ratio(CIR), impulsive index, and the phase difference between signal and interferer in the environment of cochannel PSK inter-ference and impulsive noise. We hays derived a general equation of the probability density function (p.d.f.) of output of coherent phase detector. And the error rate of the received binary PSK(BPSK) signal has been numerically evaluated. The graphic results show us that the best case is the situation of the signal and the inter- ferer meet with orthogonal phase.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.4
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• pp.387-394
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• 2013

As the feature size of integrated circuits continues to decrease, the challenge of achieving an oxidation-free exposed layer after photoresist (PR) stripping is becoming a critical issue for semiconductor device fabrication. In this article, the hydrogen plasma characteristics in direct plasma and the PR stripping rate in remote plasma were studied using a $120{\Phi}$ cylindrical inductively coupled plasma source. E mode, H mode and E-H mode transitions were observed, which were defined by matching the $V_{rms}$ and total impedance. In addition, the dependence of the E-H mode transition on pressure was examined and the corresponding plasma instability regions were identified. The plasma density and electron temperature increased gradually under the same process conditions. In contrast, the PR stripping rate decreased with increasing proportion of $H_2$ gas in mixed $H_2/N_2$ plasma. The decrease in concentration of reactive radicals for the removal of PR with increasing $H_2$ gas flow rate suggests that NH radicals have a dominant effect as the main volatile product.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2A
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• pp.108-113
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• 2011

In this paper, we propose QAPM(Quadrature Amplitude Position Modulation) modulation scheme for improving power efficiency and we compare existing PSSK(Phase Silence Shift Keying) and QAPM. An existing PSSK Modulation is extension from PSK modulation technique. The conventional PSSK modulation technique can be regarded as an extension from PSK modulation. And this PSSK has better power efficiency than PSK modulation. The Bandwidth efficiency of PSSK is half than PSK, but improved BER(Bit Error Rate) performance. A propose QAPM scheme is build on QAM. And BER performance of QAPM is better than PSSK because BER performance of QAM is better than PSK. In this paper, we compare PSSK and QAPM regard to bit error rate and throughput.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.10 s.89
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• pp.952-960
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• 2004

PSK(Phase Shift Keying) is useful because of the power and spectral efficient modulation. In this paper, no additional hardware will be needed to support various transmit mode in the suggested DSP scheme. We design and implement the synchronization algorithm for M-ary PSK(M=2, 4) demodulator based on DSP scheme, instead of complex analog PSK demodulator. TMS320C6203 is used as DSP. We check the all kinds of waveforms via the graph view window after software programming the emulation on the DSP tool. The result of implementation proves that demodulator using the suggested algorithm has equal performance with demodulator using analog circuits.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.3
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• pp.3-10
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• 2016

To establish a network environment where multiple wireless personal area networks(WPAN) are simultaneously operating in the same area, we need to consider the effects of inter-device interference. The extent of interference effect from neighboring frequency channel interferer may be different depending on the modulation types that are used for constructing the wireless network. If a modulation scheme with high spectral side lobes is used, the spatial separation between devices plays a major role in determining the amount of interference from neighboring frequency channel interferer. In this paper, we investigate the effect of inter-device interference in the overlapped raised cosine offset quadrature-quadrature phase shift keying (ORC-$OQ^2PSK$) modulation based WPAN. By comparing the results with those of GFSK modulation based WPAN, we verify the feasibility of ORC-$OQ^2PSK$ based WPAN.

• Journal of Navigation and Port Research
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• v.38 no.3
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• pp.211-216
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• 2014

In this paper, high throughput method is studied to provide floating objects with broadband service as ship by using satellite. In recent, satellite broadcastings standard is based on DVB-S3 for communication service using wireless device on navigation communication by satellite. LDPC codes are iterative coding algorithm proposed in DVB-S3. In this paper, FTN technique is applied to LDPC codes with 8-PSK modulation and then present the method to alleviate performance degradation due to FTN through BICM-ID. BICM-ID is the method to improve performance by calculating a new LLR from hard-decision value of decoder output. DVB-S2 system with 8-PSK modulation and FTN technique based on iterative decoding had a better performance than DVB-S2 with 8-PSK modulation and FTN technique over Gaussian channels.