The general goal of this paper is to extend the parallel-beam projection-slice theorem to divergent fan-beam and cone-beam projections without rebinning the divergent fan-beam and cone-beam projections into parallel-beam projections directly. The basic idea is to establish a novel link between the local Fourier transform of the projection data and the Fourier transform of the image object. Anal...

Performance improves in terms of coverage in the MC-CDMA & CDMA network with the help of simulation model and an evaluation method for the smart antenna system is presented. The EC/Io coverage area is presented with the proposed method that can show the impact of smart antenna system on the function of antenna type and beam width. The performance improvements are remarkable in the smart antenna...

The laser damage resistance of optical coatings is a key point for a large number of applications. The aim of this work is to test and analyze the laser damage resistance of a thin film material commonly used for high power applications (SiO2) and deposited with different techniques: Electron Beam Deposition, Ion Assisted Deposition, Low Voltage Reactive Ion Plating and Dual Ion Beam Sputtering...

We present a free-space optical interconnect system capable of dynamic closed-loop optical alignment using a microlens scanner with a proportional integral and derivative controller. Electrostatic microlens scanners based on combdrive actuators are designed and characterized with vertical cavity surface emitting lasers (VCSELs) for adaptive optical beam tracking in the midst of mechanical vibra...

Multi-beam antenna is drawing attention due to its power-saving and interference-reducing. A topology control algorithm K-DRNG based on multi-beam antenna in heterogeneous wireless Ad Hoc network is proposed. The algorithm is mainly composed of three phases. In the stage of information collection, each node collects information of neighborhood by adjusting the transmitting power and controlling...

This paper introduces the dynamic modelling of a single-link flexible manipulator with two cables. The end-effector is attached at distal end link and tensed cables are used to suppress vibration. considered as an Euler-Bernoulli beam cable massless spring. By applying Hamilton's principle, set nonlinear equations motion derived boundary constraints. A calculation method proposed determine natu...

background: physical wedges are still widely used as beam modifiers in external beam radiotherapy. however the presence of them in the beam trace may cause beam hardening which may not be considered in many treatment planning systems. the aim of this study is to investigate the beam hardening effect generated by physical wedges via different beam quality indexes as photon spectrum, half value l...

We experimentally demonstrate an inter-satellite laser link acquisition scheme for GRACE Follow-On. In this strategy, dedicated acquisition sensors are not required-instead we use the photodetectors and signal processing hardware already required for science operation. To establish the laser link, a search over five degrees of freedom must be conducted (± 3 mrad in pitch/yaw for each laser beam...

Atmospheric free-space optical (FSO) transmission using intensity modulation and direct detection (IM/DD) can provide high-speed links for a variety of applications, being an interesting alternative to consider for next generation broadband in order to support large bandwidth, unlicensed spectrum, excellent security, and quick and inexpensive setup [9]. Recently, the use of FSO transmission is ...