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Bit Error Probability (bit + error_probability)
Selected AbstractsOn frequency domain equalization for MC-CDMA in Nakagami fading channels,EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 1 2004Mohammed Abdel-Hafez In this letter, we evaluate the performance of multicarrier code division multiple access (MC-CDMA) in terms of average bit error probability (BEP) in Nakagami fading channels. The results are applicable to MC-CDMA systems employing coherent demodulation with maximal-ratio combining (MRC) or equal gain combining (EGC) reception. The effects of fading parameters and number of users are presented. The accuracy of the proposed analysis is demonstrated by computer simulations. The BEP performance of the EGC receiver in the uplink is highly influenced by the fading parameter compared with that of the MRC receiver. The EGC receiver outperforms the MRC receiver in the downlink, but the MRC receiver gives almost the same performance as the EGC in the uplink. Copyright © 2004 AEI [source] A forward-only recursion algorithm for MAP decoding of linear block codesINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 8 2002Hans-Jürgen Zepernick Abstract The evolution of digital mobile communications along with the increase of integrated circuit complexity has resulted in frequent use of error control coding to protect information against transmission errors. Soft decision decoding offers better error performance compared to hard decision decoding but on the expense of decoding complexity. The maximum a posteriori (MAP) decoder is a decoding algorithm which processes soft information and aims at minimizing bit error probability. In this paper, a matrix approach is presented which analytically describes MAP decoding of linear block codes in an original domain and a corresponding spectral domain. The trellis-based decoding approach belongs to the class of forward-only recursion algorithms. It is applicable to high rate block codes with a moderate number of parity bits and allows a simple implementation in the spectral domain in terms of storage requirements and computational complexity. Especially, the required storage space can be significantly reduced compared to conventional BCJR-based decoding algorithms. Copyright © 2002 John Wiley & Sons, Ltd. [source] Error performance for relaying protocols with multiple decode-and-forward relaysINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 8 2010Wenbo Xu Abstract This paper investigates the error performance of three relaying protocols with multiple decode-and-forward relays. In the first protocol, relays that can decode correctly will forward the signals from source. Nevertheless, selection cooperation (SC) and opportunistic relaying (OR) are adopted to select only a single relay to forward in the other two protocols, respectively. At sufficiently high signal-to-noise ratio, the upper bounds on bit error probability are derived for three protocols, where the developments apply for various channel fading models. Simulation results are provided to verify the tightness of the analytical bounds, and the performance comparisons among different relaying protocols are presented. Copyright © 2010 John Wiley & Sons, Ltd. [source] On convexity of MQAM's and MPAM's bit error probability functionsINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 11 2009M. Naeem Abstract For MQAM and MPAM with practical values of M and Gray mapping, we provide a rigorous proof that the associated bit error probability (BEP) functions are convex of the signal-to-noise ratio per symbol. The proof employs Taylor series expansions of the BEP functions' second derivatives and term-by-term comparisons between positive and negative terms. Convexity results are useful for optimizing communication systems as in optimizing adaptive transmission policies. Copyright © 2009 John Wiley & Sons, Ltd. [source] On the error probability of quasi-orthogonal space,time block codesINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 10 2008Jae-Dong Yang Abstract In this paper, we derive the exact pairwise error probabilities (PEPs) of various quasi-orthogonal space,time block codes (QO-STBCs) using the moment generating function. By classifying the exact PEPs of QO-STBCs into three types, we derive the closed-form expression for each type of PEP. Based on these closed-form expressions, we obtain the union bounds on the symbol error probability and bit error probability for QPSK modulation. Through simulation, it is shown that these union bounds are quite tight. Copyright © 2008 John Wiley & Sons, Ltd. [source] BPSK and QPSK non-linear satellite communication system performance in the presence of cochannel interferenceINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 3 2003Mihajlo C. Stefanovic Abstract Taking the uplink and downlink cochannel interference and noise into account, the analytical expressions are derived for determining the bit error probability in detecting a binary phase-shift-keying (BPSK) and a quaternary phase-shift-keying (QPSK) Gray coded signal, transmitted over a satellite system exhibiting amplitude modulation-to-amplitude modulation (AM/AM) conversion effects and amplitude modulation-to-phase modulation (AM/PM) conversion effects. On the basis on the derived theoretic formulae, using real-life system parameters, numerical results are obtained and presented. We point out the explicit comparisons of satellite communication system performance obtained when a satellite transponder amplifier is modelled by a hard-limiter and those obtained when both AM/AM and AM/PM non-linearities of the satellite transponder amplifier are taken into consideration. Copyright © 2003 John Wiley & Sons, Ltd. [source] Analyzing GPS signals to investigate path diversity effects of non-geostationary orbit satellite communication systemsINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 6 2002Hsin-Piao Lin Abstract The concept behind path diversity is that a user who can access several satellites simultaneously will be able to communicate more effectively than a user who could only access one. The success of this method depends on the environment, the satellite constellation, and diversity combining technology. This paper explores the path diversity effects of non-geostationary orbit (NGO) satellite personal communication services, for different degrees of user mobility, under various scenarios, using the constellation of the global positioning system (GPS). Measurements are taken near downtown Taipei. Three types of mobilities (fixed-point, pedestrian, and vehicular) are examined, and the switch diversity and maximum ratio combining method are applied to determine the path diversity gain and calculate bit error probability. The error probability performance of applying diversity schemes in coherent binary phase shift keying (BPSK) and non-coherent differential phase shift keying (DPSK) modulations over Rician fading channels are also analysed and evaluated by using the characteristic function method. The results show that fading can be significantly reduced and diversity greatly increased. A significant diversity gain and improvement in bit error rate (BER) can be expected in all cases by simply applying switch diversity scheme. Besides, for the maximum ratio combining method, the results imply that summing two satellite signals suffices to increase diversity and improve the bit error rate performance. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||