F. Javier López-Martínez

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We analyze a class of generalized two-ray (GTR) fading channels that consist of two line-of-sight (LOS) components with random phase plus a diffuse component. We derive a closed-form expression for the moment-generating function of the signal-to-noise ratio (SNR) for this model, which greatly simplifies its analysis. This expression arises from the(More)
The communication between two legitimate peers in the presence of an external eavesdropper is studied from a physical-layer security perspective in the context of free-space optical (FSO) communications. We discuss viable mechanisms to eavesdrop the communication and study the effect of random optical irradiance fluctuations inherent to FSO communications(More)
This paper presents a new connection between the generalized Marcum-Q function and the confluent hypergeometric function of two variables, Φ3. This result is then applied to the closed-form characterization of the bivariate Nakagami-m distribution and of the distribution of the minimum eigenvalue of correlated non-central Wishart matrices, both important in(More)
A general framework for the bit error rate (BER) analysis of quadrature amplitude modulation (QAM) systems is presented. This analysis is valid for any QAM system with independent bit mapping for in-phase and quadrature components and includes previous analyses in the literature as particular cases. We use this methodology to analyze BER in maximal ratio(More)
In this paper, we present a novel analytical framework for the calculation of the level crossing rate (LCR) and the average fade duration (AFD) of fading channels sampled at a certain sampling period <i>T</i><sub>S</sub>. These expressions are valid for arbitrary fading distributions with arbitrary correlation and can be easily computed in terms of the(More)
We present a novel relationship between the distribution of circular and non-circular complex Gaussian random variables. Specifically, we show that the distribution of the squared norm of a non-circular complex Gaussian random variable, usually referred to as the squared Hoyt distribution, can be constructed from a conditional exponential distribution. From(More)
A blind method for jointly estimating and correcting time, carrier frequency and sampling clock frequency synchronization in OFDM based systems is proposed. The algorithm is particularlly suitable for low-cost terminal implementations, since it provides a great efficiency in terms of hardware complexity. Its performance has been tested on a real system,(More)
We introduce the fluctuating two-ray (FTR) fading model, a new statistical channel model that consists of two fluctuating specular components with random phases plus a diffuse component. The FTR model arises as the natural generalization of the two-wave with diffuse power (TWDP) fading model; this generalization allows its two specular components to exhibit(More)