This paper proposes a theoretical study to characterize the transmission of optical code division multiple access (CDMA) systems deploying polarization shift keying (PolSK) over a free space optical (FSO) link under the impact of atmospheric turbulence. In our analysis, a novel transceiver architecture for atmospheric OCDMA FSO systems based on polarization modulation with direct detection is p...

A nematic liquid crystal adaptive optics system (NLC AOS) was assembled for a 2.16-m telescope to correct for atmospheric turbulence. LC AOS was designed and optimized with Zemax optical software. Second, an adaptive correction experiment was performed in the laboratory to test the performance of the NLC AOS. After the correction, the peak to valley (PV) and root mean square (RMS) of the wavefr...

In this paper, we theoretically analyze the performance of multiple-input multiple-output (MIMO) free-space optical (FSO) systems. The MIMO/FSO average channel capacity (ACC), which is expressed in terms of average spectral efficiency (ASE) is derived taking into account the atmospheric turbulence effects on the MIMO/FSO channel. They are modeled by log-normal and the gamma-gamma distributions ...

Flowing low temperature atmospheric pressure plasma devices have been used in many technological applications ranging from energy efficient combustion through to wound healing and cancer therapy. The generation of the plasma causes a sudden onset of turbulence in the inhomogeneous axisymmetric jet flow downstream of the plasma plume. The mean turbulent velocity fields are shown to be self-simil...

A number of remote-sensing wind-measuring instruments, such as LIDAR and radar wind profilers, have been set up in the vicinity of the Hong Kong International Airport (HKIA) for monitoring of low-level windshear and turbulence. The combined usage of wind data from a radar wind profiler and boundary layer temperature profiles from a ground-based microwave radiometer in turbulence application is ...

Shear layer separated from a bluff bodyshaped structure is very sensitive to the inflow turbulence. Appropriate numerical simulation of the atmospheric boundary layer plays key points in the numerical study of the aerodynamic forces experienced by the structures immersed in the ABL. This paper describes the methods to simulate the inflow turbulence corresponding to different surface roughness. ...

We derived the average bit error rate (BER) of coherent free-space optical (FSO) systems with digital binary phase shift keying (BPSK) modulations over atmospheric turbulence channels with a gamma–gamma distribution. To obtain a generalized derivation in a closed-form expression, we used special integrals and transformations of the Meijer G function. Furthermore, we numerically analyzed and sim...

We show that, when a partially coherent beam propagates through an inhomogeneous medium such as atmospheric turbulence, the phase randomization that is induced is less effective in degrading the spatial coherence properties. By evaluating the final beam widths we report what is to our knowledge the first experimental demonstration that, on propagation through thermlly induced turbulence, a part...

The bit error rate (BER) expression and performance of free-space optical communication link in clear but turbulent atmosphere using subcarrier intensity modulation (SIM) with differential phase shift keying (DPSK) is presented. The practical linear combining technique suitable for differentially modulated data (selection combining) is considered and its performance evaluated under weak atmosph...

We inquire about the properties of 2D Navier-Stokes turbulence simultaneously forced at small and large scales. The background motivation comes by observational results on atmospheric turbulence. We show that the velocity field is amenable to the sum of two auxiliary velocity fields forced at large and small scale and exhibiting a direct enstrophy and an inverse-energy cascade, respectively. Re...