• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.8
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• pp.2900-2922
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• 2021

In this paper, the power spectral density(PSD) for Multilevel Minimum Shift Keyed signal with modulation index h = 1/2 (M-ary MSK) are derived using the mathematical method of the Markov Chain model. At first, according to an essential requirement of the phase continuity characteristics of MSK signals, a complete model of the whole process of signal generation is built. Then, the derivations for autocorrelation functions are carried out precisely. After that, we verified the correctness and accuracy of the theoretical derivation by comparing the derived results with numerical simulations using MATLAB. We also divided the spectrum into four components according to the derivation. By analyzing these figures in the graphic, each component determines the characteristics of the spectrum. It is vital for enhanced spectral characteristics. To more visually represent the energy concentration of the main flap and the roll-down speed of the side flap, the specific out-of-band power of M-ary MSK is given. OMLCD(Optimum Maximum Likelihood Coherent Detection) of M-ary MSK is adopted to compare the signal received with prepared in advance in a code element T to go for the best. And M-ary MSK BER(Bit Error Rate) is compared with the same ary PSK (Phase Shift Keying) with M=2,4,6,8. The results show the detection method could improve performance by increasing the length of L(memory inherent) in the phase continuity.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.04a
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• pp.212-218
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• 1987

The error rate equations of digital modulatuon techniques(M-ary PSK MSK Multi-level QAM) have been derived in the environment of Qaussian noise and Jamming And the results are shown in the figures as parameters of carrier power to noise power ration(CNR) carrier power to Jamming power ration(CJR) Jamming power to carrier power ration(JCR) alteration figure of envelope of Jamming(M) As the results of analysis the system performance is more degreeded by Qau-ssian Famming than Tone Famming In case that envelope of Famming has m-distribution, the s/stem parformance is desreeded in the deep alteration of envelope

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1984.10a
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• pp.28-36
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• 1984

The error rate performances of digital modulation systems which are influenced by impulsive noise have been studied in the environment of electromagnetic interference(EMI). We have derived the error probability equations of L-level ASK, M-ary PSK, MSK, QAM, and APK signals. Using these derived equations, we have evaluated the performance of each system and compared each other.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.10 no.1
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• pp.17-30
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• 1985

The error rate performances of digital modulation systems in fluenced by impulsive noise have been investigated and discussed in the enviroment of electromagnetic interference(EMI). Using the derived equations for the probabilities of error of L-level ASK, M-ary PSK, MSK, QAM, and APK signals, the error rate performance of each system has been evaluated and compared each other. The results show that, in the case of gaussian noise enviornment, PSK system is superior to the other systems and the digital amplitude modulation systems are inferior on the contrary. In the environment of impulsive noise, the MSK at low interfere level shows the best error rate performance but in the high level interferer environment, the PSK shows the best error rate performance. Also it is known that the digital amplitude modulation systems are scarcely influenced by the variation of interfere level.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.3
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• pp.36-54
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• 1995

The error performance of digital radio signals (i.e., M-ary PSK signal, DQPSK signal, MSK signal, GMSK signal) interfered by impulsive noise and electromagnetic interference (EMI) is analyzed and discussed. In analysis at first, the error rate equations have been derived in an electromagnetic interference plus impulsive noise environment. And then, the error performance has been evaluated and shown in figures as a function of carrier-to-noise ratio, carrier-to-interference ratio, impu- lsive index, gaussian noise to impulsive noise power ratio, and interference index to measure the amount of error degradation in digital radio signals. From the obtained results we have known that in the presence of m-distributed tone interference plus inpulsive noise, the more significant the electromagnetic interference amplitude varies, the more significant performance degradation is produced. The listing the digital radio signals from the most degraded to the least is that DQPSK, GMSK, QPSK and MSK signal. In the constant amplitude tone interference plus impulsive noise environment, the effect of in- terference nearly disappears over about 20dB in CIR. The effect of constant tone interference on error rate performance is reduced more remarkably in the region from 10dB to 15dB in CIR. In both enviroments of m-distributed tone interference and constant amplitude tone interference, the more electromagnetic interference amplitude varies and CIR increases, the more error perfor- mance is improved. But it is found out that the performance can not be improved significantly even the electromagnetic interference becomes weak. This describes that the impulsive noise affects dominantly to the performance degradation.