• Title/Summary/Keyword: closed form expression

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On the Optimal Antenna Weighting Method for Closed-Loop Transmit Antenna Diversity with Average and Peak Power Constraints (평균전력과 첨두전력 제한이 있는 폐루프 송신 안테나 다이버스티 시스템에서의 최적 안테나 가중치 방식 연구)

  • Lee, Ye-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.7A
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    • pp.694-699
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    • 2007
  • We consider an optimal antenna weighting scheme for a closed-loop transmit antenna diversity system in Rayleigh fading channels. We derive a closed-form expression for the optimal transmitter weights that minimize the average bit error rate (BER) subject to fixed average and peak transmit power constraints. It is shown that the peak power limitation degrades the average BER performance more significantly as the available average power and/or the number of transmit antennas increase.

General Expression for Outage Probability with MRC Reception over Rayleigh Fading Channels (레일리 페이딩 채널에서 MRC 결합 기법 적용과 수학적 기법을 통한 Outage 확률 분석)

  • Bao, Vo Nguyen Quoc;Kong, Hyung-Yun;Hong, Seong-Wook
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.155-156
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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 outage probability for repetition code problem. A variety of simulations is performed and shows that they match exactly with analytic ones.

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Impact of Rician Fading on BER Performance on Intelligent Reflecting Surface NOMA Towards 6G Systems

  • Chung, Kyuhyuk
    • International Journal of Advanced Culture Technology
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    • v.10 no.3
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    • pp.307-312
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    • 2022
  • The commercialization of the fifth generation (5G) mobile systems has quested enabling technologies, such as intelligent reflecting surface (IRS) transmissions, towards the sixth generation (6G) networks. In this paper, we present a bit-error rate (BER) performance analysis on IRS transmissions in 5G non-orthogonal multiple access (NOMA) networks. First, we derive a closed-form expression for the BER of IRS-NOMA transmissions under Rician fading channels. Then, by Monte Carlo simulations, we validate the proposed approximate BER expression, and show numerically that the derived BER expression is in good agreement with Monte Carlo simulations. Furthermore, we also analyze the BER performance of IRS-NOMA networks under Rician fading channels with different numbers of reflecting elements, and demonstrate that the performances improve monotonically as the number of reflecting devices increases.

Behrens-Fisher Problem from a Model Selection Point of View

  • Jeon, Jong-Woo;Lee, Kee-Won
    • Journal of the Korean Statistical Society
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    • v.20 no.2
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    • pp.99-107
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    • 1991
  • Behrens-Fisher problem is viewed from a model selection approach. Normal distribution is regarded as an approximating model, A criterion, called TIC, is derived and is compared with selection criteria such as AIC and a bootstrap estimator. Stochastic approximation is used since no closed form expression is available for the bootstrap estimator.

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An Ordered Successive Interference Cancellation Scheme in UWB MIMO Systems

  • An, Jin-Young;Kim, Sang-Choon
    • ETRI Journal
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    • v.31 no.4
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    • pp.472-474
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    • 2009
  • In this letter, an ordered successive interference cancellation (OSIC) scheme is applied for multiple-input multiple-output (MIMO) detection in ultra-wideband (UWB) communication systems. The error rate expression of an OSIC receiver on a log-normal multipath fading channel is theoretically derived in a closed form solution. Its bit error rate performance is analytically compared with that of a zero forcing receiver in the UWB MIMO detection scheme followed by RAKE combining.

Spiral Inductor Design for Quality Factor

  • Lee, Sang-Gug;Kim, Sin-Cheol
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.2 no.1
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    • pp.56-58
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    • 2002
  • A closed form expression for the quality factor of the spiral inductor, methodologically, is presented as a function of the inductance ($L_{ind}$), metal-line width (W), spacing (S), inner and the diameter ($D_i$). For a given inductance, the dependences of quality factor on W, S, and $D_i$ are analyzed, and suggested the design optimization guidelines.

A Theory on the Construction of Binary Sequences with Ideal Atutocorrelation

  • No, Jong-Seon;Yang, Kyeong-Cheol;Chung, Ha-Bong;Song, Hong-Yeop
    • Journal of Electrical Engineering and information Science
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    • v.2 no.6
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    • pp.223-228
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    • 1997
  • In this paper, we present a closed-form expression of binary sequences of longer period with ideal autocorrelation property in a trace representation, if a given binary sequence with ideal autocorrelation property is described using the trace function. We also enumerate the number of cyclically distinct binary sequences of a longer period with ideal autocorrelation property, which are extended from a given binary sequence with ideal autocorrelation property.

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BER Analysis of Coherent Free Space Optical Systems with BPSK over Gamma-Gamma Channels

  • Lim, Wansu
    • Journal of the Optical Society of Korea
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    • v.19 no.3
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    • pp.237-240
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    • 2015
  • We derived the average bit error rate (BER) of coherent free-space optical (FSO) systems with digital binary phase shift keying (BPSK) modulations over atmospheric turbulence channels with a gamma-gamma distribution. To obtain a generalized derivation in a closed-form expression, we used special integrals and transformations of the Meijer G function. Furthermore, we numerically analyzed and simulated the average BER behavior according to the average SNR for different turbulence strengths. Simulation results are demonstrated to confirm the analytical results.