Performance of PPM on terrestrial FSO links with turbulence and pointing errors

Rate-Adaptive Free-Space Optical Links Over Atmospheric Turbulence and Misalignment Fading Channels

“…Then, once no more diversity gain is available, the rate reduction can be increased by using variable silence periods in order to increase the PAOPR. Novel closed-form asymptotic expressions are derived when the irradiance of the transmitted optical beam is susceptible to either a wide range of turbulence conditions (weak to strong), following a gamma-gamma distribution of parameters α and β, or pointing errors, following a misalignment fading model, as in [16][17][18]38], where the effect of beam width, detector size and jitter variance is considered.…”

“…The capacity calculation and the analysis of error rate performance for FSO links over log-normal and gamma-gamma turbulence and misalignment fading channels is presented in [8] using a wave optics based approach. In [18,39], a wide range of turbulence conditions with gamma-gamma atmospheric turbulence and pointing errors is also considered on terrestrial FSO links, deriving closed-form expressions for the error-rate performance in terms of Meijer's G-functions. In [36], average capacity optimization is considered in this same context by numerically solving the derivative of the corresponding capacity expression, also mathematically treated as a Meijer's G-function.…”

“…Novel closed-form asymptotic expressions are derived when the irradiance of the transmitted optical beam is susceptible to either a wide range of turbulence conditions (weak to strong), following a gamma-gamma distribution of parameters α and β, or pointing errors, following a misalignment fading model, as in [16][17][18]38], where the effect of beam width, detector size and jitter variance is considered. Obtained results provide significant insight into the impact of various system and channel parameters, showing that the time-diversity order that can be fully exploited is independent of the pointing error when the equivalent beam radius at the receiver is at least 2(min{α, β}) 1/2 times the value of the pointing error displacement standard deviation at the receiver.…”

An Overview of the Physical Insight and the Various Performance Metrics of Fading Channels in Wireless Communication Systems

“…It is worth mentioning here, that the ergodic capacity is a very significant metric for the study of the wireless optical communication links, due to the strong influence of the atmospheric conditions in their performance, see e.g. (Andrews et al, 1999;Gappmair et al, 2010;Garcia-Zambrana, Castillo-Vasquez & Castillo-Vasquez, 2010;Garcia-Zambrana, Castillo-Vazquez & Castillo-Vazquez, 2010;Li & Uysal, 2003;Liu et al, 2010;Peppas & Datsikas, 2010;Popoola et al, 2008;Sandalidis & Tsiftsis, 2008;Tsiftsis, 2008;Vetelino et al, 2007;Zhu & Kahn, 2002). More specifically, the fast changes of the atmospheric turbulence conditions fades fast the transmitted signal and as a result, the estimation of the instantaneous channel capacity is nearly meaningless in this area of wireless communications.…”

New Results in DF Relaying Schemes Using Time Diversity for Free-Space Optical Links

“…In [7], the effects of atmospheric turbulence and misalignment considering aperture average effect were considered to study the outage capacity for single-input/single-output (SISO) links. In [8,9], a wide range of turbulence conditions with gamma-gamma atmospheric turbulence and pointing errors is also considered on terrestrial FSO links, deriving closed-form expressions for the error-rate performance in terms of Meijer's G-functions. In [10,11], comparing different diversity techniques, a significant improvement in terms of outage and error-rate performance is demonstrated when multiple-input/multiple-output (MIMO) FSO links based on transmit laser selection are adopted in the context of wide range of turbulence conditions with pointing errors.…”