Average bit error probability for the λ-MRC detector under Rayleigh fading

Permutation index-quadrature spatial modulation: A spectral efficient spatial modulation for next generation networks

A closed-form approximate expression for the average bit error probability (ABEP) of multi-hop multi-branch cooperative networks is derived. The cooperative amplify-and-forward (AF) relaying scheme includes M separate branches between the source node and the destination node, and each branch comprises a certain number of relays. Furthermore, we consider independent and non-identical Rayleigh fading links between successive nodes in each branch. Numerical results are also provided and compared with Monte Carlo simulations.

The performance of a multicarrier direct sequence code division multiple access (MC-DS-CDMA) system in fading environment has been extensively analysed in the literatures. The analysis that is available in the literatures did not take into account the impact of jamming and channel estimation errors on the performance of the system. In this study, closed-form expressions of the average bit error probability (BEP) of the MC-DS-CDMA system with channel estimation errors in the presence of partial band, broadband and multitone jamming are derived in a Rayleigh fading channel. The analysis shows that the magnitude of the normalised correlation between the actual and the estimated complex fading channel gain, A, greatly affects the performance of the MC-DS-CDMA system. For large signal-to-noise ratio, the average BEP with A=1 and without multiple access interference (MAI) tends to zero. When A≠1, the BEP of the system exhibits an error floor even without MAI. This error floor increases as the number of users increases. It is also shown that increasing the number of the system subcarriers enhances the system performance against jamming.

In this letter we propose a unified analytical expression for the average bit error probability of dual-hop amplify- and-forward relaying systems operating in the presence of both fast fading and shadowing. In order to provide a realistic end-to- end performance of the considered system we assume that both hops are subject to independent but not necessarily identically distributed Extended Generalized-K fading. Our newly derived formula is obtained in terms of the bivariate H-Fox function. A computationally efficient algorithm to evaluate the average bit error probability is also proposed. The accuracy of the proposed method is substantiated by various numerically evaluated and computer simulation results.

The optimum detection of binary antipodal signals in additive white Gaussian noise (AWGN) channels with Gaussian channel estimation error has been studied in prior work. In this paper, we present the optimum detector based on the maximum- likelihood criterion for binary orthogonal signals in the presence of Gaussian distributed channel estimation error and AWGN. It is shown that the optimum detector is a linear combination of the optimum coherent and optimum noncoherent detectors. We derive the exact closed-form expression of the average bit error probability of the proposed optimum detector in Rayleigh fading channels with AWGN. It is found that if the variance of channel estimation error for a given average SNR is greater than a threshold, then orthogonal signalling outperforms antipodal modulation, and the analytical expression of this threshold is derived.

Using a Maclaurin series expansion of the conditional (on the carrier phase error) bit error probability of binary and quaternary phase-shift keying (BPSK and QPSK, respectively) and then averaging this result over both the statistics of the carrier phase error and the channel fading, closed-form expressions for the average bit error probability are derived in a form that lend themselves toward obtaining simple formulas for the associated noisy reference loss. Numerical evaluation of this loss based on the use of these formulas is shown to provide excellent accuracy when compared with the exact evaluation, which requires two-fold numerical integration. Although the method is specifically applied to BPSK and QPSK, it is easily extended to other forms of modulation whose conditional bit error probability is known in a closed form.

In this paper, a new multiple‐input multiple‐output transmission technique calledquadrature spatial modulation (QSM)is proposed and analyzed in the presence of imperfect channel estimation at the receiver. In QSM, conventional spatial constellation diagram of spatial modulation (SM) system is expanded to include both in‐phase and quadrature components. As such, significant enhancement in the overall spectral efficiency is achieved while retaining all inherent advantages of SM technique, such as inter‐channel interference avoidance, single radio frequency chain transmitter and low receiver complexity. It is shown that significant performance enhancements can be achieved as compared with SM, Alamouti, and spatial multiplexing systems. Besides, the impact of Gaussian imperfect channel estimation on the performance of QSM system is studied. A closed‐form expression for the pairwise error probability of generic QSM system is derived and used to calculate a tight upper bound of the average bit error probability over Rayleigh fading channels with perfect and imperfect channel knowledge. Also, simple asymptotic expression is derived and analyzed. Obtained Monte Carlo simulation results highlight the accuracy of the conducted analysis. Copyright © 2014 John Wiley & Sons, Ltd.

The performance of a digital wireless network that operates in a Rayleigh fading environment in the presence of Gaussian noise and heavy-tailed impulsive interference that can be modelled by an α -stable process is investigated. Such wireless networks include ad hoc or cognitive radio networks that operate in an unbounded fading/shadowing environment with a Poisson interference field. For the system under consideration, a novel closed-form expression for the average bit error probability of digital modulation schemes, valid for any arbitrary real values of the characteristic exponent, α , is derived. The validity of the proposed formulation is attested through Monte Carlo simulation results.

Sums of fading envelopes occur in several wireless communications applications. The exact mathematical solution to this statistic is, however, rather intricate. In this paper, we derive a novel closedform approximation to the sum of not necessarily identically distributed Nakagami-m random variables. The necessary parameters of the approximate solution are estimated by using the well-known expectation maximization algorithm with a Nakagami-m mixture model. The proposed approximation finds applicability in obtaining important performance metrics of communications systems where sums of variates arise. More specifically, we apply the proposed method to derive a closed-form expression for average bit error probability (ABEP) of multibranch equal-gain combining receivers. The presented models are general and can be applied to any modulation scheme. Furthermore, simplified asymptotic closed-form expressions for the ABEP have been derived to examine the achievable diversity and coding gains. Finally, the performance of the proposed approach is verified by comparing itself against both the exact evaluation and the previous results in the literature.

Analysis of SWIPT based dual-hop AF relay with SSK modulation over Nakagami-m fading channel

Recently, orthogonal time frequency space modulation with index modulation (OTFS-IM) has been proposed, which can achieve better bit error rate (BER) performance than conventional OTFS. In this letter, a new transmission scheme, OTFS with in-phase and quadrature index modulation (OTFS-I/Q-IM), is presented to increase the spectral efficiency of OTFS-IM, in which additional information bits are carried through the grid index of OTFS block in in-phase and quadrature dimensions. Furthermore, the analytical expressions of average bit error probability (ABEP) and the maximum peak to average power ratio (PAPR) are derived to evaluate the performance of the proposed scheme. Simulation results demonstrate the enhanced performance of the proposed scheme in high-mobility scenarios.

A three-hop long range communication system with mixed fading for smart grid (SG) wide area network (WAN) is proposed. The three hops proposed here are power line communication (PLC), radio frequency (RF) and free space optical (FSO) in cascade. The smart meter (SM) transfers the data to the access point (AP) through a PLC link. The AP is acting as a decode-and-forward (DF) relay. It retransmits the data to data aggregator unit (DAU) through RF link. The DAU also acts as a DF relay and retransmits the information to meter data management system (MDMS) through FSO link. The PLC, RF, and FSO links are distributed with Log-Normal, Nakagami-m, and Gamma-Gamma distribution, respectively. The modulation scheme considered here is binary phase shift keying (BPSK). A closed form expression for average bit error probability (ABEP) is obtained. Numerical and Monte-Carlo simulation results demonstrate the effect of impulsive noise scenario in the PLC channel, fading severity in Nakagami-m channel, and different FSO parameters in SG communication system.

This paper analyzes the performance bound of variable gain relaying over non-identical Nakagami-m fading channel, and the closed-form expressions for average bit error probability (ABEP) of binary phase shift keying (BPSK)modulation and multiple amplitude modulation (M-AM) are derived. Numerical and simulation results show that the deduced performance bound is a tight lower bound especially at medium and high signal-to-noise ratio (SNR).

The performance of a two hop amplify-and-forward relay system, where the source-relay and the relay-destination channels experience Rayleigh and Rician fading respectively, is investigated. We derive exact and lower bound expressions for the outage probability and average bit error probability, where the bounds become tight at high signal-to-noise ratios (SNR). Our results are verified through comparison with Monte Carlo simulations, where we also illustrate the positive impact of the Rician factor on the system performance.

In this paper, we investigate the performance of the Viterbi decoding algorithm with/without Automatic Repeat reQuest (ARQ) over a Rician flat fading channel with unlimited interleaving. We show that the decay rate of the average bit error probability with respect to the bit energy to noise ratio is at least equal to d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</sub> at high-bit energy to noise ratio for both cases (with ARQ and without ARQ), where d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</sub> is the free distance of the convolutional code. The Yamamoto-Itoh flag helps to reduce the average bit error probability by a factor of 4(d) <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</sub> with a negligible retransmission rate. We also prove an interesting result that the average bit error probability decays exponentially fast with respect to the Rician factor for any fixed bit energy per noise ratio. In addition, the average bit error exponent with respect to the Rician factor is shown to be d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</sub> .