• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.10
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• pp.951-963
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• 1991

In this paper M-ary Psk system for digital land mobile radio utilized the raised-cosine filter instead of LPF with rectangular frequency characteristic as luniting channel bandwidth are implemented to measure their performance and effect of ISI and jitter. Also the error probability is calcylated on the condition of fast Rayleihg fading, cochannel interference and AWGN, It is found that QPSK and 8-PSK system with 2-branch diversity, can be improved by 3 or 5 time of spectral effciency respectively, comparinng with one of the non diversity QPSK and 8.PSK system.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.1
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• pp.24-31
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• 2015

A differential codebook using M-ary phase shift keying (M-PSK) constellation as its codeword elements, is proposed for Long term evolution (LTE), LTE-Advanced (LTE-A), and/or WiMAX systems. Due to the temporal correlation of the adjacent channel, the consecutive precoding matrices are likely to be similar. This approach quantize only the differential information of the channel instead of the whole channel subspace, which virtually increase the codebook size to realize more accurate quantization of the channel. Especially, the proposed codebook has the same properties of LTE release-8 codebook that is, constant modulus, complexity reduction, and nested property. The mobile station can be designed by using a less expensive non-linear amplifier utilizing the constant modulus property. Computer simulations show that the capacity of the proposed codebook performs better than LTE release-8 codebook with the same amount of feedback information.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.6
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• pp.1004-1015
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• 1994

Modulation type classifier based on statistical moments has been successfully employed to classify PSK signals. Previously, the classifier developed utilizes the statistical moment of samples of the received signal phase, which may be difficult to extract from received signal. In this paper we propose a new moments-based classifier to classify PSK signals by using the moments of the demodulated signal for PSK. THe demodulated signal can be easily extracted from the conventional demodulation of PSK. The evaluation of the performance of the proposed classifier for PSK signals has been investigated in additive white Gaussian noise environment using the exact distribution of the demodulated signal. The performances of classifier in terms of probability of misclassification were evaluated. We found that the coherent system classifier gave 4dB improvement for BPSK and 3dB for QPSK over noncoherent system classifier, when the probability of misclassification is 10 and m equals to 4.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.7 no.1
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• pp.1-14
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• 1996

The purpose of this paper is to analyze the performance of M-ary PSK communication system according to the types of electromagnetic interference in an impulsive noise environment. We have introduced Gaussian, sinusoidal and rectangular waves as a electromagnetic interference. Using the derived equations, we evaluated the error performance of the BPSK and QPSK system in the presence of electromagnetic interference and impulsive noise. From results, we have obtained that the Gaussian wave produced the most significant performance degradation and that sinusoidal wave produced more performance degradation than rectangular wave. Therefore, without knowing the types of electromagnetic interference, it is best to regard it as Gaussian wave when designing a communication system. In addition, we could found out that the error performance degrades as impulsive noise becomes strong and the error performance can not be improved significantly even the electromagnetic interference becomes weak. Therefore, this describes that the impulsive noise affects dominantly to the performance degradation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.2A
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• pp.91-98
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• 2009

This paper provides new exact-closed form expressions for average SER and average BER as well as outage probability for M-PSK signaling with selection combining over independent but non-identically distributed Rayleigh fading paths. The validity of these expressions is verified by the Monte-Carlo simulations. All of numerical results are in excellent agreement with simulation results.

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.175.2-175.2
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• 2000

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.178.2-178.2
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• 2001

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.11A
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• pp.1053-1062
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• 2008

This paper provides a general and compact expression for the probability density function (pdf) and the moment-generating function (MGF) of the maximal ratio combiner output over Rayleigh fading channels. It is then used to derive closed form expression bit error rate (BER) for M-PSK, M-PAM and M-QAM, respectively. A variety of simulations is performed and shows that they match exactly with analytic ones.

• Journal of electromagnetic engineering and science
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• v.7 no.4
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• pp.183-189
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• 2007

When the M-ary signal experiences the Rayleigh fading, the diversity schemes can reduce the effect of fading since the probability that all the signals components will fade simultaneously is reduced considerably. The symbol error probabilities for various M-ary signals, such as MDPSK(M-ary DPSK) and MPSK(M-ary PSK), are mathematically derived for the Selection Combining 2(SC-2) and Selection Combining 3(SC-3) demodulation system which requires a less complex receiver than maximum ratio combining(MRC). The propagation model used in this paper is the frequency-nonselective slow Rayleigh fading channel corrupted by the additive white gaussian noise(AWGN). The numerical results presented in this paper are expected to provide information for the design of radio system using M-ary modulation method for above mentioned channel environment.

• Journal of Communications and Networks
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• v.11 no.5
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• pp.480-488
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• 2009

Cooperative transmission is an effective solution to improve the performance of wireless communications over fading channels without the need for physical co-located antenna arrays. In this paper, selection combining is used at the destination instead of maximal ratio combing to optimize the structure of destination and to reduce power consumption in selective decode-and-forward relaying networks. For an arbitrary number of relays, an exact and closed-form expression of the bit error rate (BER) is derived for M-PAM, M-QAM, and M-PSK, respectively, in both independent identically distributed and independent but not identically distributed Rayleigh fading channels. A variety of simulations are performed and show that they match exactly with analytic ones. In addition, our results show that the optimum number of relays depend not only on channel conditions (operating SNRs) but also on modulation schemes which to be used.