• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.352-357
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• 2000

The symbol error probability for the coherent detection of MPSK signals in additive white Gaussian noise(AWGN) can be evaluated exactly for M=2 and M=4. The MPSK symbol error probability bounds obtained in the past are simple to calculate, but not accurate. More recently, very tight bounds have been proposed, but they are complex to calculate. In this paper to obtain a simple and accurate lower bound for coherent MPSK symbol error probability in AWGN, we consider the symbol error probability for MPSK in Nakagami fading case first. Then as the Nakagami fading index m approaches to infinity, we obtain the symbol error probability for the MPSK in AWGN.

• ETRI Journal
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• v.28 no.6
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• pp.793-795
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• 2006

When quadrature error exists, the shape of the M-ary phase shift keying (MPSK) signal constellation becomes skewed-elliptic. Each MPSK symbol takes on a different symbol error probability (SEP) value. The analytical results presented thus far have been derived from studies which examined the SEP problem assuming that the SEP of each MPSK symbol is equally likely; therefore, those results should not be treated as offering a complete solution. In this letter, we present a new and more complete solution to the SEP problem of MPSK by relaxing the above assumption and finding the expressions for the average as well as individual SEP in the presence of quadrature error.

• Journal of Advanced Navigation Technology
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• v.7 no.2
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• pp.141-148
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• 2003

This paper presents and compares several techniques that detect the symbol rate of unknown received signal. Symbol rate is detected from the power spectral density of the circuits such as the delay and multiplier circuit, the square law circuit, and analytic signal, etc. As a result of discrete Fourier transform of the output signals of these circuits, a lot of spectral lines and some peaks appear in frequency domain and the position of first peak is corresponding to the symbol rate. If a spectral line on the frequency that is not located in symbol rate is larger than the first peak, the symbol rate is erroneously detected. Thus, the ratio between the value of first peak and the highest side spectral line is used for the measure of the performance of symbol rate detector. For the MPSK modulation, the analytic signal method shows better performance than the delay and multiplier and square law circuits when the received signal power is lager than -20dB. It is also noted that the delay and multiplier circuit is not able to detect the symbol rate for the QAM modulation.

• ETRI Journal
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• v.31 no.3
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• pp.345-347
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• 2009

This letter presents an alternative analytical expression for computing the probability of an M-ary phase shift keying (MPSK) wedge-shaped region in an additive white Gaussian noise channel. The expression is represented by the cumulative distribution function of known noncentral F-distribution. Computer simulation results demonstrate the validity of our analytical expression for the exact computation of the symbol error probability of an MPSK system with phase error.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.10A
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• pp.807-815
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• 2003

MultiCode-CDMA (MC-CDMA) system of chip level MPSK incorporating with clipper (MP-CDMA)[l] shows constant envelope signal which can mitigate the performance degradation due to nonlinear transmit amplifier. In this paper, modulation is modified to carry out differential encoded MPSK rather than MPSK. The modified system is called DMP-CDMA. DMP-CDMA using differential detection has advantages on receiver complexity and pilot overhead. However, it is inferior to coherent detection by about 4.0dB due to inherent power inefficiency of noncoherent detection and the error propagation. Multiple symbol differential detection is employed in order to improve DMP-CDMA using differential detection. As the result, the performance of DMP-CDMA system is improved about 3.6dB compared to differential detection.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11C
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• pp.1045-1052
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• 2005

The symbol error probability of M-ary PSK (MPSK) and QAM (MQAM) systems using the branch with the largest signal-to-noise ratio (SNR) at the output of L-branch selection combining (SC) in frequency-nonselective slow Nakagami fading channels with an additive white Gaussian noise (AWGN) is derived theoretically For integer values of the Nakagami fading parameter m, the general formula for evaluating symbol error rate (SER) of MPSK signals in the independent branch diversity system comprises numerical analyses with the integral-form expressions. An exact closed-form SER performance of MQAM signals under the effect of SC diversity via numerical integration is presented. These performance evaluations allow designers to determine M-ary modulation methods for Nakagami fading channels.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.12
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• pp.2696-2705
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• 1997

An exact experssion for the average symbol error rate(SER) of L-order selection diversity for MPSK signals in a frequency-nonselective slowy m-distributed Nakagami fading and additive white Gaussian noise(AWGN) is determs of finite sums is obtained. To derive the SER of MPSK signals with selection combining, the new expression of pdf is introduced and many other mathmatical methods are used. When fading index m is 1, the derived exppression lead to those of MPSK with selection combining in Rayleight fading channels. The results show that the error probability decreases as the order of diversity increases.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3C
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• pp.314-319
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• 2010

The chirp spread spectrum (CSS) technique that spreads the data signal over a wider frequency band via chirp signal for transmission has attracted much attention in the field of wireless communications due to capability to resist multipath fading signals. However, there has been little mathematical analysis for the performance of CSS-based communication systems in the multipath fading environments. In this paper, we study the influence of the multipath channel on the direct modulation (DM) scheme with M-ary phase shift keying (MPSK). When a chirp signal is transmitted on the Rayleigh fading channel and affected by additive white Gaussian noise (AWGN), we derive the theoretical performance. From numerical results, it is confirmed that the analytic symbol error rate (SER) agrees closely with the empirical SER.

• International Journal of Contents
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• v.11 no.1
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• pp.7-14
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• 2015

In this paper, we derive the outage probability for M-ary phase shifting keying (MPSK) and M-ary quadrature amplitude modulation (MQAM) burst transmission (BT) of adaptive decode-and-forward (ADF) cooperative relay systems over quasi-static Rayleigh fading channels. Within a burst, there are pilot symbols and data symbols. Pilot symbols are used for channel estimation schemes and each relay node's transmission mode selection schemes. At first, we focus on ADF relay systems in which the probability density function (PDF) is derived on the basis of error events at relay nodes corresponding to channel estimation errors. Next, the average outage probability is derived as an approximate expression for an arbitrary link signal-to-noise ratio (SNR) for different modulation orders. Its accuracy is demonstrated by comparison with simulation results. Further, it is confirmed that BT-ADF relay systems with pilot symbol based channel estimation schemes enables to select correctly decoded relay nodes without additional signaling between relay nodes and the destination node, and it is verified that the ideal performance is achieved with small SNR loss.

• Journal of information and communication convergence engineering
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• v.2 no.3
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• pp.145-148
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• 2004

The performances of M-ary signals using L-branch maximum ratio combining (MRC) diversity reception in correlated Nakagami fading channels are derived theoretically. The coherent reception of M-ary differential phase shift keying (MDPSK), phase shift keying (MPSK), and quadrature amplitude modulation (MQAM) is considered. It is assumed that the fading parameters in each diversity branch are identical. The general formula for evaluating symbol error rate (SER) of M-ary signals in the independent branch diversity system is presented using the integral-form expressions.