In free-space optical communication links, atmospheric turbulence causes fluctuations in both the intensity and the phase of received light signal, impairing link performance. In this paper, we describe several communication techniques to mitigate turbulence-induced intensity fluctuations, that is signal fading. These techniques are applicable in the regime in which the receiver aperture is sma...

Energy detection is a reliable non-coherent signal processing technology of spectrum sensing of cognitive radio networks, which thanks to its low complexity, no requirement of priori received information and fast sensing ability etc. Since the excellent performance of energy detection would be actually affected by physical multipath fading, this paper is concentrating on characteristics analysi...

This paper explores and compares FER (Frame Error Rate) of a MAC (Medium Access Control) layer in the IEEE 802.11 a/g/n wireless LAN. It is evaluated under the fading wireless channel, using theoretical analysis method. It is analyzed by using the number of stations with both variable payload size and mobile speed on the condition that fading margin and transmission probability are fixed. Espec...

The capacity of multiple-access channels subject to fading has attracted much recent interest exemplified by [I, and references therein]. The spectral efficiency (total capacity per chip) of the additive white Gaussian noise synchronous direct-sequence spread spectrum channel with perfect power control and randomly chosen spreading sequences was obtained in [2] as a function of the system load ...

date bunch fading disorder (dbfd) has been one of the major issues facing date palm growers in recent decades. this order has caused high and non-compensable losses to date palm product. despite numerous studies, predominantly focusing on the causes and mitigation methods of this disorder, no precise influencing factors have been established and practices which can completely control it are not...

The aim of this study was to investigate the performance enhancement of dual relay cooperative wireless network by using Amplify and Forward (AF) relaying protocol in Rician fading channel with different Kfactors. The bit error rate (BER) and BER gain by using AF scenario in Rician fading channel are derived. The results obtained from the proposed models are compared to AF scenario in Rayleigh ...

We develop a characterization of fading models, which assigns a number called logarithmic Jensen’s gap to a given fading model. We show that as a consequence of a finite logarithmic Jensen’s gap, approximate capacity region can be obtained for fast fading interference channels (FF-IC) for several scenarios. We illustrate three instances where a constant capacity gap can be obtained as a functio...

Visual stimuli fade from awareness under retinal stabilization or careful fixation, a phenomenon documented by Troxler more than 200 years ago. Research on visual fading during normal visual fixation typically has been restricted to discrete, simple, low-contrast shapes presented peripherally against a uniform or textured background. In four experiments, we document a striking new visual fading...

To enhance the reliability of long wireless link, a relay is placed between transmitter and receiver which break the link into two parts: transmitter to relay called 1st hop and relay to receiver called 2nd hop; such arrangement is called two hop wireless links. In two-hop wireless communication sometimes 1st and 2nd hops are affected by different types of fading called asymmetric fading enviro...